CRCA Education Series. Self-Adhering Membrane Roofing Systems for Low Slope Roofs

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1 CRCA Education Series Self-Adhering Membrane Roofing Systems for Low Slope Roofs

2 CRCA is a Registered Provider with the American Institute of Architects Continuing Education Systems. Credit earned upon completion of this program will be reported to CES records for all AIA members. Certificates of Completion for non-aia members are available upon requests. This program is registered with AIA/CES for continuing professional education. As such, it does not included content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material product. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.

3 Learning Objectives After completing this course, you will be able to: State the definition of a low slope roof Describe some of the historical and technical developments in self-adhering roofing systems Describe the components of a self-adhering roofing assembly Describe one or more key technical developments of self-adhered roofing systems Describe the principle factors that need to be considered in the design of a self-adhering roofing system Describe the key considerations needed for the successful installation of a self-adhering roofing system

4 Low Slope Roofing Overview Low Slope Roofs These roofs have a slope of 3" per foot or less, according to the National Roofing Contractors Association (NRCA) The minimum slope for a roof, as mandated by building codes, is 1/4" per foot Depending upon a structure's individual design, more slope may be required to assure adequate drainage and prevent ponding water

5 Low Slope Roofing Overview Roofing Demand by Building Type $ Institutional 19% Other 6% Industrial 22% Source: The Freedonia Group, Inc Office & Commercial 53%

6 Low Slope Roofing Overview Roofing Demand by Application $ New Construction 20.7% $1.4 Billion Reroofing 79.3% $5.4 Billion Source: The Freedonia Group, Inc. 2006

7 Low Slope Roofing Overview Annual Number of Modified Bitumen Squares Shipped Numbers in (000 s) SBS APP Self- Adhering Self-Adhering Underlayment ,455 6, , ,762 6, , ,445 7, , ,044 7, , ,335 7, , ,133 6,656 1,007 17,274 Note: Data from Asphalt Roofing Manufacturers Association - Summary of Asphalt Roofing Industry Shipments for All Reporting Companies; No information on Self-Adhering shipments prior to 2000.

8 Low Slope Roofing Overview Low Slope Roofing Advancements The past 20 to 30 years have seen significant technological developments These developments are the result of the industry's ongoing research Many roof system choices are available for low slope bituminous roof applications Self-adhering modified bitumen systems (or SAMBs) are one of the most recent roof system developments

9 Self-Adhering Roofing Systems Overview Beginnings of Self-Adhering Roofing Waterproofing 1960 s Roofing - Europe - mid 1970 s More recent introduction of higher quality (better tackiness) in Europe in the early 1990s Carlisle Grace Polyguard Firestone

10 Technical Developments in Self- Adhering Roofing Systems Trends in the MB Self-Adhering Roofing Systems Industry Beginnings of self-adhering application Early usage Eave edge, valley underlayment Exposed residential add-ons and low-slope applications Porches, Florida rooms, carports, breezeways, etc.

11 Self-Adhering Roofing Systems Overview Entry Into U.S. Market Late 1970 s Early 1980 s Self Adhered SBS / Polyethylene & Foil Sheets 40-50mil Early 1990 s SBS / fiberglass, polyester reinforced, granular surfaced sheets Future.

12 Self-Adhering Roofing Systems Overview Self Adhered Modified Bitumen Roofing Membrane 1960 s-70s technological advances in asphalt sciences originating in Europe led to the development of modifiers APP (atactic polypropylene) SBS (styrene-butadiene-styrene) When added to unblown (unoxidized) asphalt, these impart either plastic (APP) or rubber (SBS) characteristics These additives provide enhanced performance characteristics to traditional asphalt Combination Hybrids - Proprietary Blends New Adhesives

13 Self-Adhering Roofing Systems Overview Self Adhered TPO Hot melt pressure-sensitive adhesive 100% solids Double-sided release liner Rolled, not broomed Thicknesses 45 & 60-mil Sheet sizes 5 and 10-foot widths Carlisle 50 and 100-foot lengths

14 Self-Adhering Roofing Systems Overview Self Adhered TPO Seaming Heat-welded

15 Self-Adhering Roofing Systems Overview Self Adhered TPO Temperatures 50F+ Substrates Insulations, Plywood, OSB, Gypsum Detailing Same details and accessories standard TPO End laps - welded reinforced TPO overlays Angle changes - membrane secured with fasteners and plates

16 Self-Adhering Roofing Systems Overview Developments in U.S. Usage Self-adhering systems primary uses - application method restrictions: Risk of fire Environmental concerns Smell Lack of equipment access Specifically. Roofing and re-roofing - historical structures Other combustible (wood) deck structures Healthcare and educational facilities

17 Technical Developments in Self- Adhering Roofing Systems Self-Adhering Roofing Systems Characteristics Environmentally Friendly No asphalt fumes or unpleasant odor during application Ease of Application Less Mess Speed Good for Poor Access Jobs Color Complement Ability With steep slope roof Systems Can Be Used Over Many Types of Decks Nailable (wood, etc.) Non-nailable (concrete, steel decks, etc.) Over Insulation

18 Technical Developments in Self- Adhering Roofing Systems Self-Adhering Roofing Systems Characteristics No Torch or Hot Asphalt Needed Improved Safety Reduced Insurance Exposure Cleanliness Minimal Tools and Equipment Needed Durability EPDM Roofing Association

19 Self-Adhering Roofing Systems Overview Low Slope Self-Adhering Roofing Systems Requirements Waterproof Meet structural load requirements Resistant to fire and wind uplift Provide UV deflection Compatible with insulation where applicable Provide a suitable surface for necessary routine foot traffic to access rooftop equipment All components of the low slope self-adhering roof assembly must be compatible with one another Necessity for future repair and recovering possibilities in the design of a roof should be taken into consideration Temperature Limitations 50F+ Clean, dry, no dust

20 Self-Adhering Roofing Systems Overview Components of Low Slope Self-Adhering Roof Systems The three basic components of a low slope self-adhering assembly are: Roof deck Insulation Roof membrane

21 Use of Layered Self-Adhering Roofing Systems 1, 2-Ply and 3-Ply Systems Based on Roof Needs TPO 1-Ply System MB s - 2-Ply System Comprised of a base sheet and cap sheet For use on small, residential projects MB s - 3-Ply System Comprised of base sheet, mid-ply membrane and cap sheet For use on large, commercial projects Surface Film Adherence Base Mid Ply Cap A surface film on top of the base sheet or mid-ply membrane designed to improve adherence and durability

22 Self-Adhering Roofing Systems Overview Installation Guidelines- Low Slope Self-Adhering Roof Systems Roof membrane layout always begin at the low point of the roof MB s - Self Adhered Seams TPO s - Heat Welded Seams All membrane plies are installed with overlapping side and endlaps. Sidelaps of the various plies are offset MB s - T-Laps Sealed, TPO s T-Laps, End Laps Covered. While every aspect of the low slope self-adhering roof specification and the quality of the installation is important, flashing and termination details are critical

23 Technical Developments in Self- Adhering Roofing Systems Self-Adhering MB Roofing Systems Characteristics Newest Technology Latest in asphalt technology Offers substantial waterproofing Carriers: fiberglass, polyester mats - stable Dedicated primers and mastics to complete installation Weathering grade compound top side - adhesive asphalt bottom layer Different from 1980 s versions

24 Three-Layer Self-Adhering Roofing Systems Overview of Self-Adhering Systems Installation Application recommended above F (10 C) Low-side, shingle fashion Cleanliness Dispose of tear-off film Dust End lap preparation Adhesive Hot air gun, Welding, Patching Roller (heavyweight) to press into place T-Lap Sealing End Lap Treatment

25 Three-Layer Self-Adhering Roofing Systems MB Installation Details Rain Gutter 2-Ply Installation

26 Three-Layer Self-Adhering Roofing Systems Installation Details 3-Ply Installation

27 Three-Layer Self-Adhering Roofing Systems MB Installation Details (Cont) Flashing Specifications Two main types: Membrane (base flashing) Metal (counter-flashing and cap flashing) Polyglass

28 Three-Layer Self-Adhering Roofing Systems MB Installation Details (Cont) Perimeter Detail

29 Three-Layer Self-Adhering Roofing Systems MB Installation Details Shingle Transition

30 Self-Adhering Roofing Systems Code Information ASTM Standards None yet for specific SBS/APP/TPO Self Adhered Low Slope sheets Work in progress to develop standards to address APP and SBS based selfadhesive membranes used in both steep-slope and low-slope applications ASTM D1970, Standard Specification for Self-Adhering Polymer Modified Bituminous Sheet Materials Used as Steep Roofing Underlayment for Ice Dam Protection for now International Code Council (ICC) Approvals ICC-Evaluation Services Reviewing Wind Uplift & Fire Ratings Available Check Classification Listings

31 Course Summary We have reviewed the following topics: The definition of a low slope roof Some of the historical and technical developments in self-adhering roofing systems The components of a self-adhering roofing assembly Key technical developments of self-adhering TPO and modified bitumen roofing systems The principle factors that need to be considered in the design of a selfadhering roofing system The key considerations needed for the successful installation of a selfadhering roofing system

32 Thank You for Your Participation?

33 CRCA Education Series Self-Adhering Membrane Roofing Systems for Low Slope Roofs