INNISGLEN CONDOMINIUMS, BELLEVUE, WASHINGTON LIMITED ROOF EXAMINATION EXECUTIVE SUMMARY

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1 th Ave NE suite B101 Bellevue WA o: / f: dimensionalbc.com GSG Group Incorporated 144 Railroad Ave. #101 Edmonds, WA Attention: RE. Mr. Bruce Goodson, LEED AP Senior Project Manager INNISGLEN CONDOMINIUMS, BELLEVUE, WASHINGTON LIMITED ROOF EXAMINATION EXECUTIVE SUMMARY Dear Bruce: We have completed the limited visual evaluation of the existing roof coverings at four units within the property; the units examined are 11, 24, 39 and 48. The evaluation was carried out with the cooperation of the individual unit owners, as well as your assistance. Where possible, the interior of the attic spaces were accessed and the condition was noted to assist our team in understanding the construction of the roofs. The roofs assemblies examined are composed of architectural grade asphalt saturated shingles, mechanically secured through a layer of underlayment into the roof sheathing. Metal flashings have been used at the interface between the roof shingles and dissimilar materials, such as projecting exterior walls and eaves. The valleys are detailed with sheet metal W valley elements, though some trough valleys are detailed with a rubberized membrane. With some exceptions noted, the roofs are generally vented through vents positioned along the eaves of the roofs; static roof vents are positioned near the ridge of most of the roofs. Venting deficiencies noted will be discussed in subsequent sections of this report. The drainage of the roofs is addressed via aluminum gutters and segmented leaders. Roof structures are conventional 2x wood trusses, or wood rafters in steep slopes. The original 1x wood skip sheathing has been abandoned in place, and is overlaid with ½ inch plywood sheathing. The shingles are secured with roofing nails into the plywood sheathing. vision knowledge solutions

2 Page 2 of 11 The attic spaces above heated living areas are insulated with blown-in cellulose insulation of unknown R value; some of the insulation has been overlaid with additional fiberglass or wool insulation. In general, all the garages examined are not insulated. By all accounts, the roofs and related roof structures are of conventional construction. Specific areas of concern are listed and discussed below: 1. Roof Ventilation. Roof ventilation is absent along the upper portion of the vaulted roofs. This condition is contrary to general building code requirements, and most shingle manufacturers. The lack of compliance with minimum code requirements will likely render any potential claim against the roofing manufacturer void should the shingles be damaged from the lack of ventilation. This condition promotes accelerates deterioration of the shingles. Moreover, if moisture is allowed within the attic, this condition will promote accelerated deterioration of the roof because the roof is not vented and cannot dissipate moisture. This condition requires remediation. 2. Defective Step Flashings. This component should be typically installed at the transition between the roof shingles and the sloped portions of the exterior walls. This component is commonly made from sheet metal, and generally should measure min. 4 x4 in section. When properly installed, the horizontal flange is generally interwoven between the shingles, while the vertical flange should be installed up and under the siding to weather-proof such transition. See

3 Page 3 of 11 the diagram to the right, illustrating proper installation 1. This component is missing at some areas; or if provided is not properly integrated with the siding; or if provided is too small to be effective. In some areas, the step flashing was not provided; instead, the transition is detailed with a continuous metal flashing, which is not adequate for such use. The lack of a proper step flashing is contrary to general building code requirements, and most shingle manufacturers. The lack of a proper step flashing promotes the likelihood of water intrusion into the roof, into the attic, and possibly into the residence below. 3. Defective Roof to Wall Flashings. This component should be typically installed at the transition between the roof shingles and the horizontal portion of the exterior walls. This component is commonly made from sheet metal, and generally should measure min. 4 x4 in section. When properly installed, the horizontal flange is generally installed over the shingles, while the vertical flange should be installed up and under the siding to weather-proof such transition. 1 Excerpt of a diagram published by the National Roofing Contractors Association, Roofing and Waterproofing Manual, Fifth Edition.

4 Page 4 of 11 This component is installed but it is poorly integrated onto the shingles, and not properly integrated onto the siding or masonry elements. The lack of a proper roof to wall flashing is contrary to general building code requirements, and most shingle manufacturers. The lack of a proper flashing promotes the likelihood of water intrusion into the roof, into the attic, and possibly into the residence below. 4. Defective Rubber Troughs. These elements occur at certain locations where the sloped roof from the garage abuts the exterior wall of the gable end from the neighboring residences. To promote drainage, such transition is provided with a valley in form of a trough. The troughs are lined with a rubberized membrane, known as EPDM. This rubber membrane is loose laid over the trough, and then its seams are bonded by a double-sided seamer tape. Unfortunately a number of the seams are installed in such a manner that they are facing upslope, thereby bucking water. This defective installation is contrary to most shingle manufacturers and good roofing installation practices. When exposed to extended periods of water runoff, the defectively-installed seams are prone to failure.

5 Page 5 of Defective Offset Roof Flashing. This component is located at certain areas where the main roofs are offset from one another, but where opposite slopes meet, due to original architecture. Such offset transition is overlaid with a piece of sheet metal valley material. This metal is inadequately sized, is not properly integrated onto the underlayment and not fastened to prevent shifting or wind loss. The lack of a proper flashing at this location and the poor integration of the existing metal onto the roof is contrary to general building code requirements, and good roofing installation practices. This condition promotes likelihood of water intrusion into the roof, into the attic, and possibly into the residence below. 6. Improper Mechanical Ducts. Certain bathrooms, laundry and kitchen vents are routed through the attic, via flexible ducting. This type of ducting is inadequate for mechanical ducts because it is more prone to tears, kinks, undulations and disconnect from the points of discharge. This type of ducting should be avoided. 7. Deficient Mechanical Duct Flashing. All of the mechanical ducts (both flexible and solid ducting), were observed improperly terminating against the underside of a static roof vent. The roof vents are inadequate for such improper use because they do not discharge the air directly outside the attic, and because they are not provided with a

6 Page 6 of 11 backdraft baffle. This type of construction is contrary to the installation instructions of the roof accessory manufacturers and against good roofing installation practices. The improper use of the roof vents to daylight mechanical ducting lessens the roof ventilation, and may result in the accumulation of excessive moisture within the roof attic, which can lead to roof sheathing deterioration. 8. Deteriorated Exterior Chimney Masonry. These are the masonry elements that extend past the roof surface. Because they are constructed from brick/rockery/stone and mortar, they require regular and expensive maintenance. All of the masonry elements located above the roof have some degree of deterioration and lack of maintenance. Deterioration observed included algae growth; moss growth; deterioration of the mortar; separation of the mortar from the substrate; spalling of mortar and/or brick, cracking of concrete crown; and others. Additionally, a number of masonry elements are not provided with a metal cap above the flue liner extension. The lack of a metal cap allows rainwater to penetrate into the chimney below and cause additional water damage to important iron elements, such as the chimney dampers.

7 Page 7 of Active Leaks of Moisture Damage. Following are the residences that were either reported (and confirmed) or observed with active leaks or moisture damage attributable to a likely failure of a roof component: a. Unit 11. A roof leak and water damage in the northern portion of the garage was reported to us. The leak and water damage to the interior finishes were confirmed during our visit. The exact point of water intrusion is not known, however the leak is directly below an improperly installed rubber membrane, at the roof trough. b. Unit 24. We observed evidence of ongoing condensation of excess of moisture within the attic, and ongoing deterioration of the roof sheathing above living areas, where a bathroom fan is exhausted using flexible duct. This duct is then improperly terminated against the underside of a roof vent. We observed evidence of ongoing condensation of excessive moisture within the attic. The image to the right depicts droplets of water on the roofing nail tips, inside the attic of this residential unit.

8 Page 8 of 11 c. Unit 39. A roof leak and water damage in the eastern portion of the master bedroom, just north of the masonry chimney was reported to us. The roof leak and water damage to the interior finishes were confirmed during our visit. The exact point of water intrusion is not known, however the leak is directly below an improperly detailed chimney flashing. The moisture intrusion observed over the interior surface of the masonry (as observed within the attic space) is profuse. This indicates likely breaches within the masonry elements above. 10. Wood Fascia Boards. Wood fascia boards are made from conventional wood, possibly cedar. These elements are deteriorated due to aging and lack of maintenance. Deterioration of these elements will likely not cause additional damage to other components of the building, however they turn into eye-sores which may lessen the perceived value of the property.

9 Page 9 of Abandoned PVC Vent Stacks. This condition occurs at 2 of the units accessed. A PVC vent stack has been abandoned at each unit, and capped at the bottom (interior space). The stub of PVC that extends past the roof was left un-capped, as a result the abandoned PVC stacks are full of rainwater. If the containment of the PVC was to fail, the water contained within the stacks will cause some damage to the interior of the subject units. Recommendations: Following are the recommendations, in no specific order of importance, but following the general layout provided by the above report items 1 through 11: A. Roof ventilation must be restored to comply with current code. Venting calculations must be carried out to determine the size of the ventilation ports at those areas currently lacking adequate vents. The vaulted ceiling areas can be vented utilizing a continuous ridge vent, and the existing eave venting if the rates provided by each are found acceptable. B. Step Flashings. These elements must be provided where currently missing or where currently improperly installed. Besides complying with code and manufacturer s requirements, the installation of adequate step flashings will prevent additional water intrusion and water damage to the property. The installation of proper step flashings will likely require limited and targeted removal of siding, and certain laborious work at the masonry walls. C. Roof to Wall Flashings. These elements must be provided where currently missing or where currently improperly installed. Besides complying with code and manufacturer s requirements, the installation of adequate roof to wall flashings will prevent additional water intrusion and water damage to the property. The installation of proper flashings will likely require limited and targeted removal of siding, and certain laborious work at the masonry walls. D. Troughs. These must be examined to determine if more troughs were installed using reversed and inadequate laps. At the very minimum, the trough located above unit 11 should be removed and replaced, and the water damage repaired.

10 Page 10 of 11 The proper replacement of the defective trough will require limited and targeted removal of siding and roofing. E. Offset Roof Flashings. These elements should be removed and replaced with heavy lead flashings, properly integrated into the roof shingles and underlayment, and properly fastened. The proper replacement of the defective flashings will require limited and targeted removal of roofing. F. Mechanical Ducting. All flexible ducting should be removed and replaced with rigid ducting. All ducting that exhausts warm and moist air should be insulated with min. R10 to prevent condensation within the attic. All joints in the ducting should be taped to prevent air infiltration. All ducting should be daylighted through the roof using a proper mechanical duct roof flashing. Ganging of ducts should be avoided. G. Masonry Chimneys. All the masonry chimneys are overdue for extensive maintenance. At the very minimum, maintenance should include: soft bristle washing; removal of organic materials, complete tuckpointing of mortar; resetting of loose masonry elements; replacement of concrete crowns, installation of extensions to the clay flues; installation of stainless steel caps (wind screens) to the clay flue extensions; restoration of defective masonry flashings; acid washing at the end of repairs and application of clear sealer. This maintenance is very expensive due to the intensity of the laboring, as well as the amount of chimneys in the buildings. H. Wood Fascias. After testing the fascias for possible hazardous material content, the wood can be salvaged by scraping and brushing off the existing paint, followed by the application of 2 coats of oil-base primer, and 2 coats of exterior paint. Some elements may be too deteriorated to justify repairs and will have to be replaced. I. Water Filled Stacks. These should be carefully emptied from the current liquid, and then capped from the top. The manufacturer of the shingles or the roof underlayment is not known. It is our understanding that the roof was completed without securing a warranty from the installer. From our limited review of the roofs accessed, it appears the installer lacked knowledge about how to properly integrate the roof onto dissimilar materials, and also

11 Page 11 of 11 lacked knowledge about how to properly manufacture and install proper flashing elements. Roof requirements for attic ventilation and mechanically ducting were also partially ignored during the installation of the shingles. The existing roof installation requires significant work to bring it to a point of compliance with the requirements of the building code. We hope you find the above information useful, however do not hesitate to contact our office if we need to provide additional clarification. Yours sincerely, Martin C. Flores, CE, ICC, RRC Principal Dimensional Building Consultants, LLC vision knowledge solutions