Garland Canada Inc. Roof Asset Management Program Thornbury Sewer Treatment Plant Roof Report 2016 Prepared By Andrew Kukkonen Prepared For Rob Fleming
Table of Contents Thornbury Sewer Treatment Plant / Facility Summary 3 Thornbury Sewer Treatment Plant / Facility Drawing 4 Thornbury Sewer Treatment Plant / Section 1 / Construction Details 5 Thornbury Sewer Treatment Plant / Section 1 / Roof Section Photo 6 Thornbury Sewer Treatment Plant / Section 1 / 7 Thornbury Sewer Treatment Plant / Section 1 / Solution: Apr 18, 2016 20 Thornbury Sewer Treatment Plant / Section 2 / Construction Details 23 Thornbury Sewer Treatment Plant / Section 2 / Roof Section Photo 24 Thornbury Sewer Treatment Plant / Section 2 / 25 Thornbury Sewer Treatment Plant / Section 3 / Construction Details 32 Thornbury Sewer Treatment Plant / Section 3 / Roof Section Photo 33 Thornbury Sewer Treatment Plant / Section 3 / 34 Thornbury Sewer Treatment Plant / Section 4 / Construction Details 40 Thornbury Sewer Treatment Plant / Section 4 / Roof Section Photo 41 Thornbury Sewer Treatment Plant / Section 4 / 42 Army Cor Life Cycle.pdf 47 BuildingsDrLaalyArticle2015.pdf 48 HighPerfRoofSys_Canada_rev.pdf 51
Facility Summary Client: Town of the Blue Mountains Facility: Thornbury Sewer Treatment Plant Facility Data Address 1 1 Grey Street South Address 2 Unit 2 City Province Postal Type of Facility Thornbury Ontario N0H 2P0 Municipal Asset Information Name Date Installed Square Footage Roof Access Section 1 1992 1,044 Attached Ladder Section 2 1992 1,914 Attached Ladder Section 3 1992 1,085 Attached Ladder Section 4 1992 657 Attached Ladder Facility Summary Page 3 of 52
Facility Drawing Page 4 of 52
Construction Details Client: Town of the Blue Mountains Facility: Thornbury Sewer Treatment Plant Roof Section: Section 1 Information Year Installed 1992 Square Footage 1,044 Slope Dimension Low Sloped Eave Height 18' Roof Access Attached Ladder System Type Ballasted EPDM Assembly Roof # Layer Type Description Attachment R-Value Thickness 1 Deck Precast concrete Mechanically attached - - 1 Vapor Retarder 2 ply hot Hot asphalt - - 1 Insulation Phenolic Hot asphalt 19.6 2" 1 Insulation Fiberglass Hot asphalt 5.85 1.5" 1 Membrane EPDM Ballasted - - Details Perimeter Detail Flashing Material Drain System Parapet Wall Coping Cap Parapet Wall, Wall Flashing, Metal Edge, Raised Metal Edge, Drip Edge, Wall Cladding EPDM Internal Roof Drains Concrete Block Metal Inventory Inventory Type Quantity HVAC 1 Drain 2 Construction Details Page 5 of 52
Roof Section Photo Page 6 of 52
Inspection Report Client: Town of the Blue Mountains Facility: Thornbury Sewer Treatment Plant Roof Section: Section 1 Report Date: 04/18/2016 Inspection Information Inspection Date 04/18/2016 Core Data Yes Inspection Type Core Analysis Leakage Yes Deck Conditions Fair Flashing Conditions Perimeter Failed Wall Good Projections Failed Counterflashing Fair Miscellaneous Details Reglets Fair Debris Yes Control Expansion Joints Fair Ponding Water Minor Parapet Wall Good Coping Joints Fair Page 7 of 52
Perimeter Rating Condition Failed Reglet Joint Deterioration: expansion and contraction of the wall metal counter flashing coupled with the exposure to UV rays causes the sealing caulking to crack over time. This allows water to enter behind the metal and run down the wall. If any failure is present in the underlying BUR flashing membrane immediate leaks will occur. Single Ply Flashing Deterioration: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Therefore, it is extremely easy to puncture or tear. Specifically on this roof where the river rock ballast is in direct contact with the EPDM single ply flashing multiple leaks will occur from "cuts" caused by the river rock ballast. Single Ply Tenting: Single Ply Tenting occurs at the perimeter of the roof. As the single ply membrane is exposed to UV rays it shrinks. This in turn causes the perimeter to look like a tent and exerts extreme pressure on this 1 millimeter thin membrane. Couple this pressure with the brittleness of this old rubber membrane and multiple tears/punctures develop which in turn cause leaks inside the building and will lead to complete roof failure. Perimeter Flashing Deterioration: Expansion and contraction movement of the roof causes stress in the perimeter flashing causing it to tear. Moisture can then enter the roofing system and building. Moisture entry will cause damage to the insulation and reduce its insulating properties. It will also allow water to enter the building causing internal damage. Fishmouths: Wrinkles or openings at the edge of the membrane caused by poor adhesion or installation. Fishmouths are a common cause of early failure on 2-ply torch down and single ply roof systems. These systems are prone to workmanship error due to two factors (1) the manual heating/welding of the adhesive, which is very unpredictable for constant heat, and (2) the roof system only consists of 1 to 2 plies, which translates in to a very thin layer of water protection. In this case the wrong adhesive was utilized for the repair. Fastener Back-Out: This is a very common condition on this type of metal wall panel. When the metal expands and contracts the pressure causes the fasteners to create pressure on the panel increasing the size of the fastener penetrations. This coupled with thermal bridging causes the fasteners to back out of the metal. In this case water can then enter the building and walls causing leaks and in some cases damage to the mortar or concrete existing in the wall. Page 8 of 52
Field Rating Condition Poor Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Ballast Deterioration: Over time the stones or ballast on EPDM roofs split causing sharp razor-like edges, which easily puncture the single ply EPDM membrane. This is caused by thermal cycles where the ballast is extremely hot and then experiences a rapid drop in temperature due to thunderstorms or rain. Furthermore, freeze and thaw cycles also cause the above condition. Penetrations Rating Condition Failed Missing Support Insulation: rooftop equipment should always have extruded polystyrene insulation under the supports in order to protect the membrane. Over time the natural vibration of a building can cause the support to puncture the membrane, allowing moisture to enter the roofing system and cause premature failure. Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Single Ply Tears: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Couple this weakness with the common shrinking effect experienced by 8 year or older single ply systems and the facility manager is typically left with an ever increasing amount of tears causing immediate leaks. Pitch Pocket Deterioration: Metal protrusions that penetrate the roof system to allow conduits to run from the rooftop into the building. Movement from the protrusion can break the waterproofing compound, creating cracks. Over time, the release of solvents from the compound can cause the material to shrink, leaving gaps along the edges of the pan and around structural support. Water can enter through a defective pitch pan and find its way into the interior of the building. Moisture can also penetrate into the roof system leading to premature failure. Drainage Rating Condition Fair Page 9 of 52
Overall Rating Condition Failed This section is in a failed condition overall. During the interior inspection, leakage was noted along 34' of the hallway. Water was seen actively dripping onto the floor from the concrete deck above once ceiling tiles were moved out of the way. A local contractor was hired approximately 3 years ago to complete flashing repairs to all roof sections at this facility, which encompasses three different buildings. A new EPDM membrane was improperly installed over top the existing, which is failed in many areas. This includes leaks at this building, as it was leaking prior to the repairs. The new flashing was not adhered using adhesive materials typical of this type of membrane. Instead, it was loose laid over top the existing. As such, the only method of securement is that it was tucked underneath the metal counter flashing or cap. This is an inadequate method of securement, thus this repair is ineffective due to improper workmanship. The core sample was found to be wet. Wet insulation is bad for a few reasons; it greatly reduces the R-value, adding to heating and cooling costs. It poses a health and safety threat with the possibility for mold growth. And, it will ultimately destroy your structural deck as it corrodes it due to constant long term exposure. Finally, the wet insulation present is phenolic foam. All four cored roof sections have this type of insulation. Phenolic Foam: premature deck corrosion on structural steel decking has been found on many of these installations. The Phenolic Foam roof insulation manufactured in a variety of colors from 1981-1992 used a sulfonic acid as a catalyst in the process of creating the cells of the foam. If the insulation were to become wet or exposed to moisture the water dissolves the sulfonic acid forming a highly acidic compound. Unfortunately Phenolic Foam insulation, unlike other closed cell insulations, readily absorbs water just like a sponge. The super sponge characteristics of the Phenolic Foam absorb water from a leaking roof system without any immediate evidence of roof leaks within a building s interior. In addition to absorbing water, Phenolic Foam insulation boards have also been found to shrink over time by as much as an inch or more in width and length. The gaps create voids which allow for condensation conditions and the absorption of moisture at the edges of the insulation. Due to these factors, corrosion of steel decking on Phenolic Foam installations is typically found at areas of insulation joints even when the roof system is watertight. Repairs to this section and sections 2-4 could be completed, however the overall roof condition at all sections is very poor. It is likely that a proper repair would be ineffectual as the roof has already failed. These roofs are also well past their life cycle at 24 years; a typical ballasted EPDM will last a maximum of 18 years. Therefore, any potential repair would likely not solve all leaks. To solve the 34' of hallways leaks (other areas of moisture intrusion were detected inside), new flashings would need to be installed and properly tied into the failed roof membrane. Replacement is therefore the only proper solution at this facility. Page 10 of 52
Photo 1 An overview of section 1. Photo 2 The previous repair attempt was improperly completed. The new flashing membrane installed over top the existing was not adhered. As such, it can be pulled away from the substrate since there is no adhesion, rendering the repair useless. Photo 3 Fishmouths: Wrinkles or openings at the edge of the membrane caused by poor adhesion or installation. Fishmouths are a common cause of early failure on 2-ply torch down and single ply roof systems. These systems are prone to workmanship error due to two factors (1) the manual heating/welding of the adhesive, which is very unpredictable for constant heat, and (2) the roof system only consists of 1 to 2 plies, which translates in to a very thin layer of water protection. In this case the wrong adhesive was utilized for the repair. Photo 4 Single Ply Flashing Deterioration: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Therefore, it is extremely easy to puncture or tear. Specifically on this roof where the river rock ballast is in direct contact with the EPDM single ply flashing multiple leaks will occur from "cuts" caused by the river rock ballast. Page 11 of 52
Photo 5 A wider look at the location of the aforementioned deficiency. Photo 6 Single Ply Tenting: Single Ply Tenting occurs at the perimeter of the roof. As the single ply membrane is exposed to UV rays it shrinks. This in turn causes the perimeter to look like a tent and exerts extreme pressure on this 1 millimeter thin membrane. Couple this pressure with the brittleness of this old rubber membrane and multiple tears/punctures develop which in turn cause leaks inside the building and will lead to complete roof failure. Photo 7 Flashings installed over top the existing were not adhered during the recent repair. Photo 8 A small piece of silicone sealant was installed on one spot of the flashing in an attempt to adhere it. Page 12 of 52
Photo 9 Pitch Pocket Deterioration: Metal protrusions that penetrate the roof system to allow conduits to run from the rooftop into the building. Movement from the protrusion can break the waterproofing compound, creating cracks. Over time, the release of solvents from the compound can cause the material to shrink, leaving gaps along the edges of the pan and around structural support. Water can enter through a defective pitch pan and find its way into the interior of the building. Moisture can also penetrate into the roof system leading to premature failure. Photo 10 Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Photo 11 Un-adhered flashing membrane due to improper workmanship. Photo 12 Same as previous. Page 13 of 52
Photo 13 Single Ply Tears: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Couple this weakness with the common shrinking effect experienced by 8 year or older single ply systems and the facility manager is typically left with an ever increasing amount of tears causing immediate leaks. Photo 14 An improper detail. The membrane was brought up and over top the metal cap. Metal details are haphazardly connected. A proper detail would see proper fabricated metal pieces joined together by S-Locks. Photo 15 A core sample was taken to verify the roof composition and check for wet insulation. Wet insulation is bad for a few reasons; it greatly reduces the R-value, adding to heating and cooling costs. It poses a health and safety threat with the possibility for mold growth. And, it will ultimately destroy your structural deck as it corrodes it due to constant long term exposure. Photo 16 Wet phenolic foam insulation was detected. Wet Insulation: A high level of moisture intrusion into the roof system and insulation. Due to the complete failure of the membrane the insulation has become dimensionally unstable putting additional stress on the roof system and is leading to a high probability of collapse, a loss of the original investment in thermal resistance as well as a risk of mold spore development. Furthermore, prolonged moisture exposure to the structural substrate can cause severe corrosion. Page 14 of 52
Photo 17 Phenolic Foam: premature deck corrosion on structural steel decking has been found on many of these installations. The Phenolic Foam roof insulation manufactured in a variety of colors from 1981-1992 used a sulfonic acid as a catalyst in the process of creating the cells of the foam. If the insulation were to become wet or exposed to moisture the water dissolves the sulfonic acid forming a highly acidic compound. Unfortunately Phenolic Foam insulation, unlike other closed cell insulations, readily absorbs water just like a sponge. The super sponge characteristics of the Phenolic Foam absorb water from a leaking roof system without any immediate evidence of roof leaks within a building s interior. In addition to absorbing water, Phenolic Foam insulation boards have also been found to shrink over time by as much as an inch or more in width and length. The gaps create voids which allow for condensation conditions and the absorption of moisture at the edges of the insulation. Due to these factors, corrosion of steel decking on Phenolic Foam installations is typically found at areas of insulation joints even when the roof system is watertight. Photo 18 During the interior inspection, ceiling tiles were removed. Moisture was noted approximately 34' in length along the interior hallway. Page 15 of 52
Photo 19 Another look. Photo 20 Water was seen to be dripping from the precast concrete deck. Photo 21 No adhesion of the cap flashing along the leaking perimeter parapet wall. Page 16 of 52
Photo 22 Missing Support Insulation: rooftop equipment should always have extruded polystyrene insulation under the supports in order to protect the membrane. Over time the natural vibration of a building can cause the support to puncture the membrane, allowing moisture to enter the roofing system and cause premature failure. Photo 23 Single Ply Tenting: Single Ply Tenting occurs at the perimeter of the roof. As the single ply membrane is exposed to UV rays it shrinks. This in turn causes the perimeter to look like a tent and exerts extreme pressure on this 1 millimeter thin membrane. Couple this pressure with the brittleness of this old rubber membrane and multiple tears/punctures develop which in turn cause leaks inside the building and will lead to complete roof failure. Note the water trapped underneath the metal. Since this cap flashing membrane is not adhered, the metal could act as a medium for water to pass behind the membrane and leak into the area below. This is directly above the areas of leaks inside. Photo 24 Reglet Joint Deterioration: expansion and contraction of the wall metal counter flashing coupled with the exposure to UV rays causes the sealing caulking to crack over time. This allows water to enter behind the metal and run down the wall. If any failure is present in the underlying BUR flashing membrane immediate leaks will occur. Page 17 of 52
Photo 25 Some deterioration of the mortar joint is present. This is not currently at a significant enough level of deterioration to warrant corrective action. Photo 26 A closer look. Photo 27 Fastener Back-Out: This is a very common condition on this type of metal wall panel. When the metal expands and contracts the pressure causes the fasteners to create pressure on the panel increasing the size of the fastener penetrations. This coupled with thermal bridging causes the fasteners to back out of the metal. In this case water can then enter the building and walls causing leaks and in some cases damage to the mortar or concrete existing in the wall. Page 18 of 52
Photo 28 Fastener Back-Out: This is a very common condition on this type of metal wall panel. When the metal expands and contracts the pressure causes the fasteners to create pressure on the panel increasing the size of the fastener penetrations. This coupled with thermal bridging causes the fasteners to back out of the metal. In this case water can then enter the building and walls causing leaks and in some cases damage to the mortar or concrete existing in the wall. Page 19 of 52
Solution Options Client: Town of the Blue Mountains Facility: Thornbury Sewer Treatment Plant Roof Section: Section 1 Repair Options Solution Option: Repair Action Year: 2016 Square Footage: 1,044 Expected Life Years: 1 Budget Range: $5,000.00 - $10,000.00 EMERGENCY LEAK REPAIRS Please note the above cost is a budget number not a firm price. A firm price would be determined by a bid process. This repair includes the following and is performed by a contractor: Find and repair all leaks on a time and materials basis. Replace Options Solution Option: Replace Action Year: 2016 Square Footage: 1,044 Expected Life Years: 35 Budget: $130,000.00 SECTIONS 1-4 EMERGENCY ROOF REPLACEMENT OPTION 30 YEAR WARRANTY - 35 YEAR LIFE CYCLE Please note the above cost is a budget number not a firm price. A firm price would be determined by a bid process. This replacement includes the following and is performed by a contractor: This system incorporates the best performance qualities of both the single ply rubber roof system and the multi layer inorganic built-up roof system. The modified system uses intermittent layers of type III asphalt and fiberglass roofing felts along with a super thick and strong rubber modified/fiberglass reinforced bitumen cap sheet. The multiple layers are covered by a heavy top pour of type III asphalt and are surfaced with protective roofing gravel. This modified membrane dramatically improves the performance and life expectancy of the roof system. Advantages: Multiple layer construction Longer warranty and life expectancy as compared to single ply and 4 ply roof systems Highest tensile and tear strengths which helps the roof system to resist splitting and tearing Thicker membrane provides greater resistance to weather and roof traffic The modified membrane has self-healing qualities due to the manufacturing process and the low softening Solution: Apr 18, 2016 Page 20 of 52
point of the SBS modifiers The system has better low temperature flexibility, which helps it to withstand deck, building, traffic, and impact during below freezing temperatures (passed at -40 C) Modified membranes have excellent slow aging characteristics Modified systems are very applicator friendly since the membranes are factory manufactured with far more quality control and have been engineered to overcome certain application deficiencies This system provides the end user with the least amount of post installation problems and The lowest overall life cycle and maintenance costs This system will include the following: 2 ply felt vapor barrier 2.5" ISO Insulation 2.0" ISO Insulation Tapered down to minimum 1/2" Fibreboard 2 plies of HPR Glasfibre Felts 1 ply of Stressply Max as the top membrane adhered with type III hot applied asphalt. Top coat with type III hot applied asphalt and gravel for UV protection. New 24 gauge perimeter and projection metal flashing. Membrane manufacturers 30 year, No Dollar Limit, non-prorated, material and labour warranty. Replace Options Solution Option: Replace Action Year: 2016 Square Footage: 1,044 Expected Life Years: 45 Budget: $135,000.00 SECTIONS 1-4 EMERGENCY ROOF REPLACEMENT OPTION 40 YEAR WARRANTY - 45 YEAR LIFE CYCLE Please note the above cost is a budget number not a firm price. A firm price would be determined by a bid process. This replacement includes the following and is performed by a contractor: This system incorporates the best performance qualities of both the single ply rubber roof system and the multi layer inorganic built-up roof system. The modified system uses intermittent layers of type III asphalt and fiberglass roofing felts along with a super thick and strong rubber modified/fiberglass reinforced bitumen cap sheet. The multiple layers are covered by a heavy top pour of type III asphalt and are surfaced with protective roofing gravel. This modified membrane dramatically improves the performance and life expectancy of the roof system. Advantages: Multiple layer construction Longer warranty and life expectancy as compared to single ply and 4 ply roof systems Highest tensile and tear strengths which helps the roof system to resist splitting and tearing Thicker membrane provides greater resistance to weather and roof traffic The modified membrane has self-healing qualities due to the manufacturing process and the low softening point of the SBS modifiers The system has better low temperature flexibility, which helps it to withstand deck, building, traffic, and impact during below freezing temperatures (passed at -37 C) Modified membranes have excellent slow aging characteristics Modified systems are very applicator friendly since the membranes are factory manufactured with far more Solution: Apr 18, 2016 Page 21 of 52
quality control and have been engineered to overcome certain application deficiencies This system provides the end user with the least amount of post installation problems and The lowest overall life cycle and maintenance costs. This membrane utilizes revolutionary new technology to incorporate fibreglass reinforcement in an asphaltpolyurethane modified membrane. The polyurethane resin is specially formulated to extend the life of the membrane in a patent-pending "active modification" process involving chemically locking the urethane modifier to the asphalt. This provides enhanced performance characteristics. This system will include the following: 2 ply felt vapor barrier 2.5" ISO Insulation 2.0" ISO Insulation Tapered Fibreboard to 1/2" 2 plies of HPR Glasfibre Felts 1 ply of Optimax as the top membrane adhered with type III hot applied asphalt. Top coat with type III hot applied asphalt and gravel for UV protection. New 24 gauge perimeter and projection metal flashing. Membrane manufacturers 40 year, No Dollar Limit, non-prorated, material and labour warranty. Solution: Apr 18, 2016 Page 22 of 52
Construction Details Client: Town of the Blue Mountains Facility: Thornbury Sewer Treatment Plant Roof Section: Section 2 Information Year Installed 1992 Square Footage 1,914 Slope Dimension Low Sloped Eave Height 25' Roof Access Attached Ladder System Type Ballasted EPDM Assembly Roof # Layer Type Description Attachment R-Value Thickness 1 Deck Concrete Mechanically attached - - 1 Vapor Retarder 2 ply hot Hot asphalt - - 1 Insulation Phenolic Hot asphalt 19.6 2" 1 Insulation Fiberglass Hot asphalt 5.85 1.5" 1 Membrane EPDM Ballasted - - Details Perimeter Detail Flashing Material Drain System Parapet Wall Coping Cap Parapet Wall, Wall Flashing, Metal Edge, Raised Metal Edge, Drip Edge, Wall Cladding EPDM Internal Roof Drains Concrete Block Metal Inventory Inventory Type Quantity Drain 2 Construction Details Page 23 of 52
Roof Section Photo Page 24 of 52
Inspection Report Client: Town of the Blue Mountains Facility: Thornbury Sewer Treatment Plant Roof Section: Section 2 Report Date: 04/18/2016 Inspection Information Inspection Date 04/18/2016 Core Data Yes Inspection Type Core Analysis Leakage Yes Deck Conditions Fair Flashing Conditions Perimeter Failed Wall Good Projections Failed Counterflashing Fair Miscellaneous Details Reglets N/A Debris No Control Expansion Joints Fair Ponding Water Minor Parapet Wall Good Coping Joints Fair Page 25 of 52
Perimeter Rating Condition Failed Caulking Deterioration: As caulking is exposed to UV rays and temperature fluctuations it looses its flexibility and develops cracks. Once this occurs splits develop instantly allowing water to penetrate walls and buildings causing damage as well as leaks. Single Ply Tenting: Single Ply Tenting occurs at the perimeter of the roof. As the single ply membrane is exposed to UV rays it shrinks. This in turn causes the perimeter to look like a tent and exerts extreme pressure on this 1 millimeter thin membrane. Couple this pressure with the brittleness of this old rubber membrane and multiple tears/punctures develop which in turn cause leaks inside the building and will lead to complete roof failure. Single Ply Tears: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Couple this weakness with the common shrinking effect experienced by 8 year or older single ply systems and the facility manager is typically left with an ever increasing amount of tears causing immediate leaks. Single Ply Flashing Deterioration: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Therefore, it is extremely easy to puncture or tear. Specifically on this roof where the river rock ballast is in direct contact with the EPDM single ply flashing multiple leaks will occur from "cuts" caused by the river rock ballast. Field Rating Condition Poor Ballast Deterioration: Over time the stones or ballast on EPDM roofs split causing sharp razor-like edges, which easily puncture the single ply EPDM membrane. This is caused by thermal cycles where the ballast is extremely hot and then experiences a rapid drop in temperature due to thunderstorms or rain. Furthermore, freeze and thaw cycles also cause the above condition. Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Page 26 of 52
Penetrations Rating Condition Failed Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Pitch Pocket Deterioration: Metal protrusions that penetrate the roof system to allow conduits to run from the rooftop into the building. Movement from the protrusion can break the waterproofing compound, creating cracks. Over time, the release of solvents from the compound can cause the material to shrink, leaving gaps along the edges of the pan and around structural support. Water can enter through a defective pitch pan and find its way into the interior of the building. Moisture can also penetrate into the roof system leading to premature failure. Drainage Rating Condition Fair Missing Drain Screen: Drain screens help to prevent debris from entering and clogging drains and ultimately this helps prevent ponding water. Overall Rating Condition Failed This section is in failed condition. The entire northwestern perimeter is wide open. The previous repair attempt was also completed improperly. The fibreglass insulation and phenolic foam insulation underneath that are openly visible, and perimeter wood blocking is as well. When the membrane was lifted, a scurrying sound could be heard. It is likely that animals have entered here and are using the area to take refuge as a nest. All the visible insulation is soaking wet. Additionally, there was a very strong musty smell which likely indicates water damage, and could also indicate the presence of mold. The smell was exacerbated when the membrane was lifted. As with section 1, holes and tears have also formed in the flashings and seams. These roof sections are past their life expectancy and require replacement. Page 27 of 52
Photo 1 An overview of section 2. Photo 2 Single Ply Tenting: Single Ply Tenting occurs at the perimeter of the roof. As the single ply membrane is exposed to UV rays it shrinks. This in turn causes the perimeter to look like a tent and exerts extreme pressure on this 1 millimeter thin membrane. Couple this pressure with the brittleness of this old rubber membrane and multiple tears/punctures develop which in turn cause leaks inside the building and will lead to complete roof failure. Caulking Deterioration: As caulking is exposed to UV rays and temperature fluctuations it looses its flexibility and develops cracks. Once this occurs splits develop instantly allowing water to penetrate walls and buildings causing damage as well as leaks. Photo 3 This corner of the perimeter is wide open. The previous repair attempt was also completed improperly. The fibreglass insulation and phenolic foam insulation underneath that are openly visible, and perimeter wood blocking is as well. When the membrane was lifted, a scurrying sound could be heard. It is likely that animals have entered here and are using the area to take refuge as a nest. Additionally, there was a very strong musty smell which likely indicates water damage. The smell was exacerbated when the membrane was lifted. Page 28 of 52
Photo 4 Moisture was detected underneath the flashing membrane. Photo 5 Missing Drain Screen: Drain screens help to prevent debris from entering and clogging drains and ultimately this helps prevent ponding water. Photo 6 Pitch Pocket Deterioration: Metal protrusions that penetrate the roof system to allow conduits to run from the rooftop into the building. Movement from the protrusion can break the waterproofing compound, creating cracks. Over time, the release of solvents from the compound can cause the material to shrink, leaving gaps along the edges of the pan and around structural support. Water can enter through a defective pitch pan and find its way into the interior of the building. Moisture can also penetrate into the roof system leading to premature failure. Page 29 of 52
Photo 7 Perimeter flashing is wide open. Photo 8 Single Ply Tears: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Couple this weakness with the common shrinking effect experienced by 8 year or older single ply systems and the facility manager is typically left with an ever increasing amount of tears causing immediate leaks. Photo 9 During a closer inspection of the open perimeter, sulfonic acid could be seen secreting from the phenolic foam insulation. Phenolic Foam: premature deck corrosion on structural steel decking has been found on many of these installations. The Phenolic Foam roof insulation manufactured in a variety of colors from 1981-1992 used a sulfonic acid as a catalyst in the process of creating the cells of the foam. If the insulation were to become wet or exposed to moisture the water dissolves the sulfonic acid forming a highly acidic compound. Unfortunately Phenolic Foam insulation, unlike other closed cell insulations, readily absorbs water just like a sponge. The super sponge characteristics of the Phenolic Foam absorb water from a leaking roof system without any immediate evidence of roof leaks within a building s interior. In addition to absorbing water, Phenolic Foam insulation boards have also been found to shrink over time by as much as an inch or more in width and length. The gaps create voids which allow for condensation conditions and the absorption of moisture at the edges of the insulation. Due to these factors, corrosion of steel decking on Phenolic Foam installations is typically found at areas of insulation joints even when the roof system is watertight. Page 30 of 52
Photo 10 Flashings on curbs are deteriorating significantly as well. Photo 11 Same as previous. Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Page 31 of 52
Construction Details Client: Town of the Blue Mountains Facility: Thornbury Sewer Treatment Plant Roof Section: Section 3 Information Year Installed 1992 Square Footage 1,085 Slope Dimension Low Sloped Eave Height 25' Roof Access Attached Ladder System Type Ballasted EPDM Assembly Roof # Layer Type Description Attachment R-Value Thickness 1 Deck Concrete Mechanically attached - - 1 Vapor Retarder 2 ply hot Hot asphalt - - 1 Insulation Phenolic Hot asphalt 14.7 1.5" 1 Insulation Fiberglass Hot asphalt 7.8 2" 1 Membrane EPDM Ballasted - - Details Perimeter Detail Flashing Material Drain System Parapet Wall Coping Cap Metal Edge, Raised Metal Edge, Drip Edge EPDM Internal Roof Drains Concrete Block Metal Inventory Inventory Type Quantity Drain 1 Construction Details Page 32 of 52
Roof Section Photo Page 33 of 52
Inspection Report Client: Town of the Blue Mountains Facility: Thornbury Sewer Treatment Plant Roof Section: Section 3 Report Date: 04/18/2016 Inspection Information Inspection Date 04/18/2016 Core Data Yes Inspection Type Core Analysis Leakage Yes Deck Conditions Fair Flashing Conditions Perimeter Poor Wall Good Projections Poor Counterflashing Fair Miscellaneous Details Reglets N/A Debris No Control Expansion Joints Fair Ponding Water Minor Parapet Wall N/A Coping Joints Fair Page 34 of 52
Perimeter Rating Condition Poor Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Single Ply Flashing Deterioration: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Therefore, it is extremely easy to puncture or tear. Specifically on this roof where the river rock ballast is in direct contact with the EPDM single ply flashing multiple leaks will occur from "cuts" caused by the river rock ballast. Single Ply Tears: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Couple this weakness with the common shrinking effect experienced by 8 year or older single ply systems and the facility manager is typically left with an ever increasing amount of tears causing immediate leaks. Single Ply Tenting: Single Ply Tenting occurs at the perimeter of the roof. As the single ply membrane is exposed to UV rays it shrinks. This in turn causes the perimeter to look like a tent and exerts extreme pressure on this 1 millimeter thin membrane. Couple this pressure with the brittleness of this old rubber membrane and multiple tears/punctures develop which in turn cause leaks inside the building and will lead to complete roof failure. Fishmouths: Wrinkles or openings at the edge of the membrane caused by poor adhesion or installation. Fishmouths are a common cause of early failure on 2-ply torch down and single ply roof systems. These systems are prone to workmanship error due to two factors (1) the manual heating/welding of the adhesive, which is very unpredictable for constant heat, and (2) the roof system only consists of 1 to 2 plies, which translates in to a very thin layer of water protection. In this case the wrong adhesive was utilized for the repair. Field Rating Condition Poor Ballast Deterioration: Over time the stones or ballast on EPDM roofs split causing sharp razor-like edges, which easily puncture the single ply EPDM membrane. This is caused by thermal cycles where the ballast is extremely hot and then experiences a rapid drop in temperature due to thunderstorms or rain. Furthermore, freeze and thaw cycles also cause the above condition. Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Page 35 of 52
Penetrations Rating Condition Poor Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Drainage Rating Condition Fair Missing Drain Screen: Drain screens help to prevent debris from entering and clogging drains and ultimately this helps prevent ponding water. Overall Rating Poor Condition Overall, this section is in poor condition. It is in a very similar condition to sections 1 and 2, though the tears and deterioration is not as severe. However, the roof is obviously failing, as the core sample revealed wet phenolic foam insulation. This, coupled with the ineffective repair recently and advanced age of the roof, indicate it should be replaced. While steel decks are not present at any section at this facility, the presence of wet phenolic foam insulation can still damage the concrete deck. Phenolic Foam: premature deck corrosion on structural steel decking has been found on many of these installations. The Phenolic Foam roof insulation manufactured in a variety of colors from 1981-1992 used a sulfonic acid as a catalyst in the process of creating the cells of the foam. If the insulation were to become wet or exposed to moisture the water dissolves the sulfonic acid forming a highly acidic compound. Unfortunately Phenolic Foam insulation, unlike other closed cell insulations, readily absorbs water just like a sponge. The super sponge characteristics of the Phenolic Foam absorb water from a leaking roof system without any immediate evidence of roof leaks within a building s interior. In addition to absorbing water, Phenolic Foam insulation boards have also been found to shrink over time by as much as an inch or more in width and length. The gaps create voids which allow for condensation conditions and the absorption of moisture at the edges of the insulation. Due to these factors, corrosion of steel decking on Phenolic Foam installations is typically found at areas of insulation joints even when the roof system is watertight. Page 36 of 52
Photo 1 An overview of section 3. Photo 2 Missing Drain Screen: Drain screens help to prevent debris from entering and clogging drains and ultimately this helps prevent ponding water. Photo 3 Fishmouths: Wrinkles or openings at the edge of the membrane caused by poor adhesion or installation. Fishmouths are a common cause of early failure on 2-ply torch down and single ply roof systems. These systems are prone to workmanship error due to two factors (1) the manual heating/welding of the adhesive, which is very unpredictable for constant heat, and (2) the roof system only consists of 1 to 2 plies, which translates in to a very thin layer of water protection. In this case the wrong adhesive was utilized for the repair. Photo 4 Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Page 37 of 52
Photo 5 As with other sections, the recent flashing repair has no adhesion. Photo 6 Single Ply Tenting: Single Ply Tenting occurs at the perimeter of the roof. As the single ply membrane is exposed to UV rays it shrinks. This in turn causes the perimeter to look like a tent and exerts extreme pressure on this 1 millimeter thin membrane. Couple this pressure with the brittleness of this old rubber membrane and multiple tears/punctures develop which in turn cause leaks inside the building and will lead to complete roof failure. Photo 7 A closer look at the recent repair, which has no adhesion. Photo 8 Single Ply Tears: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Couple this weakness with the common shrinking effect experienced by 8 year or older single ply systems and the facility manager is typically left with an ever increasing amount of tears causing immediate leaks. Page 38 of 52
Photo 9 Single Ply Flashing Deterioration: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Therefore, it is extremely easy to puncture or tear. Specifically on this roof where the river rock ballast is in direct contact with the EPDM single ply flashing multiple leaks will occur from "cuts" caused by the river rock ballast. Page 39 of 52
Construction Details Client: Town of the Blue Mountains Facility: Thornbury Sewer Treatment Plant Roof Section: Section 4 Information Year Installed 1992 Square Footage 657 Slope Dimension Low Sloped Eave Height 18' Roof Access Attached Ladder System Type Ballasted EPDM Assembly Roof # Layer Type Description Attachment R-Value Thickness 1 Deck Concrete Mechanically attached - - 1 Vapor Retarder 2 ply hot Hot asphalt - - 1 Insulation Phenolic Hot asphalt 14.7 1.5" 1 Insulation Fiberglass Hot asphalt 3.9 1" 1 Membrane EPDM Ballasted - - Details Perimeter Detail Flashing Material Drain System Parapet Wall Coping Cap Metal Edge, Raised Metal Edge, Drip Edge EPDM Internal Roof Drains Concrete Block Metal Construction Details Page 40 of 52
Roof Section Photo Page 41 of 52
Inspection Report Client: Town of the Blue Mountains Facility: Thornbury Sewer Treatment Plant Roof Section: Section 4 Report Date: 04/18/2016 Inspection Information Inspection Date 04/18/2016 Core Data Yes Inspection Type Core Analysis Leakage Yes Deck Conditions Fair Flashing Conditions Perimeter Poor Wall Good Projections Poor Counterflashing Fair Miscellaneous Details Reglets N/A Debris No Control Expansion Joints Fair Ponding Water Minor Parapet Wall N/A Coping Joints Fair Page 42 of 52
Perimeter Rating Condition Poor Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Single Ply Flashing Deterioration: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Therefore, it is extremely easy to puncture or tear. Specifically on this roof where the river rock ballast is in direct contact with the EPDM single ply flashing multiple leaks will occur from "cuts" caused by the river rock ballast. Single Ply Tears: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Couple this weakness with the common shrinking effect experienced by 8 year or older single ply systems and the facility manager is typically left with an ever increasing amount of tears causing immediate leaks. Single Ply Tenting: Single Ply Tenting occurs at the perimeter of the roof. As the single ply membrane is exposed to UV rays it shrinks. This in turn causes the perimeter to look like a tent and exerts extreme pressure on this 1 millimeter thin membrane. Couple this pressure with the brittleness of this old rubber membrane and multiple tears/punctures develop which in turn cause leaks inside the building and will lead to complete roof failure. Fishmouths: Wrinkles or openings at the edge of the membrane caused by poor adhesion or installation. Fishmouths are a common cause of early failure on 2-ply torch down and single ply roof systems. These systems are prone to workmanship error due to two factors (1) the manual heating/welding of the adhesive, which is very unpredictable for constant heat, and (2) the roof system only consists of 1 to 2 plies, which translates in to a very thin layer of water protection. In this case the wrong adhesive was utilized for the repair. Field Rating Condition Poor Ballast Deterioration: Over time the stones or ballast on EPDM roofs split causing sharp razor-like edges, which easily puncture the single ply EPDM membrane. This is caused by thermal cycles where the ballast is extremely hot and then experiences a rapid drop in temperature due to thunderstorms or rain. Furthermore, freeze and thaw cycles also cause the above condition. Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Page 43 of 52
Penetrations Rating Condition Poor Single Ply Seam Deterioration:Due to the inherent nature of single ply membranes, which shrink with exposure to the elements, extreme pressure is present on the membrane seams. These seams are either heat welded or sealed with adhesive and cannot withstand the aforementioned pressure. Therefore, they will tear and cause immediate leaks and associated water damage inside the building. Drainage Rating Condition Fair Missing Drain Screen: Drain screens help to prevent debris from entering and clogging drains and ultimately this helps prevent ponding water. Overall Rating Condition Poor Overall, this section is in poor condition. It is in a very similar condition to sections 1, 2, and 3, though the tears and deterioration are not as severe. However, the roof is obviously failing, as the core sample revealed wet phenolic foam insulation. This, coupled with the ineffective repair recently and advanced age of the roof, indicate it should be replaced. While steel decks are not present at any section at this facility, the presence of wet phenolic foam insulation can still damage the concrete deck. Phenolic Foam: premature deck corrosion on structural steel decking has been found on many of these installations. The Phenolic Foam roof insulation manufactured in a variety of colors from 1981-1992 used a sulfonic acid as a catalyst in the process of creating the cells of the foam. If the insulation were to become wet or exposed to moisture the water dissolves the sulfonic acid forming a highly acidic compound. Unfortunately Phenolic Foam insulation, unlike other closed cell insulations, readily absorbs water just like a sponge. The super sponge characteristics of the Phenolic Foam absorb water from a leaking roof system without any immediate evidence of roof leaks within a building s interior. In addition to absorbing water, Phenolic Foam insulation boards have also been found to shrink over time by as much as an inch or more in width and length. The gaps create voids which allow for condensation conditions and the absorption of moisture at the edges of the insulation. Due to these factors, corrosion of steel decking on Phenolic Foam installations is typically found at areas of insulation joints even when the roof system is watertight. Page 44 of 52
Photo 1 Single Ply Tenting: Single Ply Tenting occurs at the perimeter of the roof. As the single ply membrane is exposed to UV rays it shrinks. This in turn causes the perimeter to look like a tent and exerts extreme pressure on this 1 millimeter thin membrane. Couple this pressure with the brittleness of this old rubber membrane and multiple tears/punctures develop which in turn cause leaks inside the building and will lead to complete roof failure. Photo 2 Open perimeter repair. Photo 3 Single Ply Flashing Deterioration: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Therefore, it is extremely easy to puncture or tear. Specifically on this roof where the river rock ballast is in direct contact with the EPDM single ply flashing multiple leaks will occur from "cuts" caused by the river rock ballast. Photo 4 Single Ply Tears: A typical single ply EPDM rubber roof membrane is approximately 1 millimeter thick. Couple this weakness with the common shrinking effect experienced by 8 year or older single ply systems and the facility manager is typically left with an ever increasing amount of tears causing immediate leaks. Page 45 of 52
Photo 5 Fishmouths: Wrinkles or openings at the edge of the membrane caused by poor adhesion or installation. Fishmouths are a common cause of early failure on 2-ply torch down and single ply roof systems. These systems are prone to workmanship error due to two factors (1) the manual heating/welding of the adhesive, which is very unpredictable for constant heat, and (2) the roof system only consists of 1 to 2 plies, which translates in to a very thin layer of water protection. In this case the wrong adhesive was utilized for the repair. Page 46 of 52
Creating a High Performance Roof System History of Low Slope Roofing In Canada Built-up roofing, which is the practice of installing multiple layers of reinforcing fabric laminated together with a waterproof agent made of tar or asphalt, has been around for over 150 years. In such a system, the tar or asphalt provides the waterproofing, and the fabric is the strength of the system. One does not survive without the other. Up until the 1930 s and 1940 s most roofs consisted of a wood or concrete deck with little or no insulation and a four- or five-ply built-up roof system. Any insulation that was installed was normally fiberboard with a maximum thickness of ½ to 1. On occasion, cork insulation was substituted. Such systems commonly lasted 25 years or more. Coal tar pitch, which is an excellent material for roofing, was used most frequently as the waterproofing glue. The roofing felts were made up of wood fiber blended with scraps of rags from the textile industry (hence the name rag felts). Coal tar pitch came from the treating of coke produced as a by-product from coal in the steel industry. In the 1950 s asphalt became more plentiful. It was easier to use and was less harmful to those using it. Steel decks also became much more common in usage. In addition to the deck and other types of structural changes, asphalt began to be substituted for coal tar pitch. Synthetics began to replace natural fibers in the textile industry and roof felts tended to be organic felts. Insulation was still predominately fiberboard, but in greater thickness. Fiberglass Insulation with higher R-Values was also introduced. In the 1960 s the industry faced rapid changes. Almost all felts were organic; steel decks were lighter in gauge; asphalt was used in 80% on the installations; exotic, high R-value insulation such as polystyrene was introduced; and, building designs became more radical. Roofs now had to work under much more adverse conditions Higher rooftop temperatures (+180 F in the summer to -40 F in the winter). The higher membrane temperatures were caused by higher R-value insulation. More equipment was mounted on the roof causing more service traffic. Lighter weight decks had more deflection causing more stress on the membrane. Roofs frequently did not drain well. While this was okay for coal tar pitch roofs, asphalt degrades under standing water. Felts were now organic which tended to pick up moisture and lose there strength rapidly. Essentially as the stresses on roofs were increased the roofing systems were becoming weaker. Problems Were Occurring On Roofs Much Sooner In order to combat these problems, new and exotic materials were introduced but did not solve the problems: Fiberglass felts were introduced and failed as they consisted of loose glass threads bonded together. As these glass felts aged, the asphalt binder tended to separate from the glass filaments. Among other things, this caused the felts to fracture. This was particularly true when these were used over soft compressible fiberglass insulation. Single ply membranes were first introduced in Canada around 1973 1974. The most prevalent membrane was EPDM and it gained popularity because to concept appeared sound. However, problems with seams and adhesives appeared with them and other types of single plies. Most single plies were developed in Europe. Modified membranes started to make their appearance in the marketplace in the mid 1970 s. Also originating from Europe, it had been found that single-plies were not the answer for all roofs. In the early 1980 s, new and improved glass felts were introduced creating an opportunity to bring about a marriage between fiberglass felts, asphalt and modified bitumen membranes. These roofs had a typical service life of fifteen to twenty years. It wasn t the built up roofing that failed in 60 s and 70 s but rather the failure of the roofing industry to recognize the new stresses that the roofs were being subjected too and with materials that were not suited to the task. During the 80 s and 90 s construction methods continued to allow for more building movement. Energy prices started to increase adding for the need for higher R-Value insulation. Unfortunately, the addition of higher R-Values caused the roof membrane temperature to elevate considerably which contributed to accelerated aging. Modified membrane technology improved with the advent of stronger reinforcing scrims containing fiberglass, polyester and hybrids containing both fiberglass and polyester. Copolymers were also introduced which further extended the performance life of modified bitumen membranes. The option of restoring roof systems also became a popular and effective option. Roof management systems also became more prevalent with the understanding that there were some basic necessary steps to create a long-term high performance roof system. Where We Are Today The most dramatic change in the industry has been the escalation of costs. Ten years ago, roof replacement costs averaged between $4 to $7 dollars per square foot, while today s costs range from $12 to $18 plus per square foot. There are also additional concerns regarding reflectivity and sustainability in relation to HVAC costs and the environment in general. The drastically rising installation costs now make it imperative to design a roof system that can last beyond 30 years. Economically replacing roofs after 15 to 20 years simply doesn t make sense. Costs have climbed due to following factors: Increased labor costs. The price of asphalt has more than doubled over the last two years increasing the cost of any asphalt related product. Polyisocyanurate insulation has doubled to tripled in cost. Disposal fees have increased. Roofing contractors insurance costs have more than tripled due to increased claims. R-Value requirements have increased due to high heating and cooling costs.
These factors are not going improve. The four step process below when implemented efficiently will bring about a roof system that can last well beyond thirty years. All four parts of this process are critical to long-term roof performance. 1. Proper Analysis, Design and Application - Boilerplate specifications simply do not work. Specifications must be tailored to fit the requirements of the building. No two roofs are the same. The current environmental conditions, details on the roofs and the client s long-term requirements must be met. Lifecycle costing should be performed. 2. Quality Products/High Performance Materials - The modified membrane has been established as a standard in long-term roofing. ASTM has created minimum standards. However, for long lasting performance, other performance standards must also be used: A. Tear and Tensile Strength Leading roofing expert Dr. Heshmat Laaly stated that superior performance in the areas of tensile and tear strength does contribute to a longer service life. B. Polymers react differently as they age. Specific modified bitumen roofing solutions are differentiated by those performance attributes they are designed to achieve. There are several primary factors defining performance in modified bitumen membranes. They break down into two specific areas, compound and reinforcement. Compound performance is a function of the component raw materials selected and blended to produce the modified bitumen. By selected quality and consistent asphalt (or bitumen) one can best control the overall long-term performance. Modified bitumen membranes can be modified with a variety of polymer types to enhance the thermal performance of the roofing system. Two of the most common polymer modifiers are SBS (styrenebutadien-styrene) and APP (atactic polypropylene). In short, SBS can be described as a rubber (or thermoplastic elastomer) while APP is best described as a plastic. Both additives help to increase the resistance to high temperature flow of the roofing membrane. While APP does little to enhance the low temperature flexibility (the temperature at which a product loses its flexibility and cracks), SBS will greatly enhance the low temperature performance. When properly formulated, SBS compounds can take flexibility down to well below -40 C. While overall content of rubber can be a good indicator of long-term performance, it is also important to look at the type and quality of the blend. Suppliers need to assure the customer that the rubber being used is properly dispersed in the compound asphalt. Proper blending can be assured by strict quality control and by observing the blend through microscopic techniques. Further, formulators can choose from several different rubber products available in the thermoplastic elastomer family. While SBS is the most common, formulators may also choose to work with SIS (styreneisoprene-styrene) or SEBS (styreneethylene-butylene-styrene). SBS, upon aging, can become stiffer over time. Contrarily, SIS will tend to become softer when it ages. By combining SBS and SIS, formulators can achieve bitumen polymer blends that age very little over time. SEBS is also designed to age very little over time. However SEBS can be very difficult to use by itself in bitumen blends. Therefore, formulators can use low ratios of SEBS to SBS to produce long-term stabilized blends. While compounds have a great effect on long-term performance, so does the reinforcement used in the modified bitumen membrane. Specifiers can choose from glass, polyester or combined glass/polyester hybrid reinforcements. Glass will tend to yield the highest tensile strength with low elongation. Polyester, on the contrary, yields moderate tensile with high elongation. The composite materials attempt to combine the two performance enhancements of high tensile and high elongation. Building owners can choose from most combinations of polymer types and reinforcements to select the modified bitumen product that is right for their specific need. By choosing wisely, consumers can pick the solution that provides the best long-term performance for their specific need and environment. C. Low-Temperature Flexibility is the lowest temperature a roofing membrane can resist cracking when wrapped around a mandrel with a given radius, and specified speed of bending after being cooled to a specific temperature. Low-temperature flexibility is important, especially in a membrane which is installed during the winter. This is also important in climates that face extreme changes in temperature. D. Sustainability - Any product that can incorporate recycled material reduces waste and in some cases greenhouse gases. The cumulative effect can trickle down and help with climate change. E. Reflectivity - In many locations, roofs are required by law to be in excess of 75% reflective. This can reduce cooling cost significantly. Energy pay back programs should be used to determine if there are significant savings. Reflective roofs also reduce the thermal shock that is acted upon a roof; however, the membrane is more susceptible to damage from foot traffic and other onsite abuses. 3. Proper Application and Regular Inspections - No matter the quality of the specification and materials, without quality installations, a roof system will not last. Proper inspections ensure quality control. 4. Regular Inspections and Preventative Maintenance Regardless of the design or quality of application, all roof systems need regular inspections and preventative maintenance. By investing one to two cents per square foot on existing roofs, most emergency leaks can be prevented and the effective service life of the roof can be extended. Roof asset management programs make it easier to control roofing assets. Warrantees are also a major factor in any roofing system choice. Warrantees should be performance based with limited restrictions. Consider the history and financial stability of the manufacturer providing the warranty. Also, be sure to check local references. Summary History shows us that roofs are facing more stress with increasing costs, thus making roofs an asset that cannot be ignored. The statement, if you fail to plan, you plan to fail has become a reality in roofing industry. A proactive approach incorporating the above four steps will reduce the life-cycle costs of any new roof system and extend the life of existing roof systems. Garland Canada Inc. For Internal Use, 03/08