Roofing Sustainability

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1 Williams Engineering Canada Inc. Roofing Sustainability Gord Rajewski R.E.T. November 19, 2009

2 Overview History of Williams Engineering Canada Who WE are today Roofing 101 Low slope (flat) roofs Sloped roofs Green Roofs Keys to Sustainable Roofing

3 Williams Engineering Canada Inc. Williams Engineering has 30+ years of experience in the Engineering Consulting Business. Branch offices located in Northern, Central, and Southern Alberta, the Arctic and Manitoba.

4 Williams Engineering Canada Inc. Multi-Discipline Engineering Building Science Structural Mechanical Geotechnical Civil Electrical

5 The design of this roof satisfies a design criteria, but is it practical?

6 Roofing 101 Low Slope (flat) Roofing Sloped Roofing

7 Two Main Configurations for Low Slope Roofing 1. Membrane is above insulation: Conventional Roof Design 2. Roofing Membrane is below Insulation Protected Roof Membrane Assembly

8 Low Slope Roofing Advantages 1. Accessibility for maintenance personnel 2. Stronger structure (support fall arrest & mechanical systems) 3. Long history of use 4. Various system types available 5. Development of New Technologies Green Roofs Materials Advances

9 Low Slope Roofing Disadvantages 1. Potentially complicated design requirements 2. Less qualified contractors available 3. Longer installation time 4. Cost

10 Low Slope Roofing Commonly used multi-ply systems Built-up Roofing (BUR) Modified Bitumen (SBS)

11 Low Slope Roofing Commonly used single-ply systems 1. Ethylene Polymer Diene Monomer(EPDM) 2. Thermoplastic Olefin (TPO) 3. Polyvinyl Chloride (PVC)

12 FAQ: How long should a roof last? Systems Average Maximum BUR 4fg iso BUR 4fg gravel BUR/PMS SBS Base/Cap Any SBS/PMS EPDM 45mil Ballast (adh laps) EPDM/PMS (adh laps) EPDM 45mil Ballast (tape) EPDM/PMS PVC

13 There are always FIVE options for the roofing on any existing building Gord s Five Options

14 GORD s Options Option 1: Do nothing (what the majority of people do) Option 2: Maintain Option 3: Repair Option 4: Retro-Fit Option 5: Replace

15 Sloped Roofing Advantages 1. Promotes Exceptional Drainage 2. Aesthetically Pleasing 3. Less Complicated (generally) 4. More Competent Contractors (less fly by-night) 5. Shorter Installation Times (New and Re-Roofing)

16 Sloped Roofing Disadvantages 1. Hazardous for maintenance personnel when: Wet Snow covered 2. Less likely to support: Fall arrest anchors Mechanical systems

17 Types of Roofing Commonly used roofing system: 1. Asphalt/Fiberglass Shingles 2. Wood Shakes/Shingles 3. Architectural Metal 4. Tiles

18 What is a Green Roof?

19 What is a Green Roof? Broad Sense Energy saving Roof formula: Light color or reflective = less cooling energy = lower utility usage Environmentally sensitive Roof consists of: Recycled or Nontoxic materials (e.g. rubber, plastic, wood, cement fiber, recycle metal/tile)

less cooling energy = lower utility usage Environmentally sensitive

20 Thoughts on Reflective Roof Surfaces What would happen if all roof tops around the world were painted white? Steven Chu, US Energy Secretary Noble Laureate in physics It would be the equivalent of reducing the carbon emissions due to all the cars on the road for 11 years.

Steven Chu, US Energy Secretary Noble Laureate in physics It would

21 Green Roofing continued High reflective roofs should be applied in locations where significant air conditioning is needed. In Canada high R-value insulation is installed within the roofs, making the roof color a secondary concern.

22 Green Roofing continued Narrow Sense A Green Roof system is an extension of the existing roof which involves: High quality water proofing and root barrier system Drainage system Filter Cloth Medium lightweight plants

23 Historical View of Green Roofing Farm House, Nova Scotia

24 Historical View of Green Roofing Heritage Square, Red Deer Built in 1887

25 Typical Green Roof Composition A Green roof should include four essential Layers: Waterproofing Drain Soil Plant Before any components are added to a roof, the structural weight limits must be determined by a professional.

26 Cross-Section of a Green Roof Diagram by Hydrotech

27 Before landscaping proceeds ensure the waterproofing system does not leak. A thorough flood test insures no leaks are present in the installation.

28 Drainage Layer Green Roofs must have a layer to prevent water from accumulating on the roof membrane surface. A good roof design will minimize water ponding

29 Drainage Layer Drain layer is applied over the entire roof area Dual purpose: 1. Keeps soil well aerated 2. Acts as a water retention layer

30 Soil Layer Soil cannot contain any silt that would clog the filter fabric. Soil mixes include Water permeable Water & air retentive Resistant to rot, heat, frost & Shrinkage Good nutrient status Provide an excellent rooting medium

31 Vegetation Layer Vegetation (green) is the most visible layer of the green roof. An experienced horticulturist should be involved in plant selection. Characteristics of plants typically used on green roofs include: Shallow root system Good regenerative qualities Resistance to direct sun, drought tolerant, frost & wind Compatibility with local range of temperature, humidity, rainfall & sun

32 Sprouting up across Canada Green Roofs to be built for the Athletic Village at the 2010 Olympic Winter Games. Green Roof Passive solar design Beyond-code insulation Low/No VOC paint Rain water used for irrigation on roof.

roof. 50% Green Roof coverage on : Multi-unit residences over

33 Green Roofing in the News In Toronto, a bylaw adopted this year requires new buildings over 2,000 square meters to have a green roof. 50% Green Roof coverage on : Multi-unit residences over six stories Schools Non-profit housing Commercial Industrial buildings

34 This is NOT a Green Roof

35 Applications of Green Roofs

36 Gardens Take Root Green Roofs- essentially rooftops as planter boxes - are sprouting up across Canada. novanait researcher Dr. Leonie Nadeau is currently conducting a study to find the best medium for both plant growth as well as withstanding conditions atop buildings in Northern Canada

37 Reasons Green Roofs Fail 1. Leaks, Clogs, or poor Drainage system 2. Lack of watering and/or poor maintenance leads to: Roof Blowing Away Fire Hazard (from growth media drying out) 3. Bad microclimate analysis 4. Growth media collapse 5. Inappropriate growth media for plant selection / poor plant selection

38 Cost of Green Roofs Initial cost Given various assembly types and projects descriptions, costs can range from: $15.00 sf to $60 sf or more Maintenance Costs Repair and Replacement come at a cost premium.

39 Achieving Sustainability in Roofing

40 Five Keys to Achieving a Sustainable Roof 1. Motivated and fully engaged client A client that knows what he/she wants and is prepared to fully fund the project 2. Motivated and fully engaged consultant Local, Knowledgeable, Experienced, and Listens well 3. Appropriate design One style does not fit all scenarios Design in keeping with available budget 4. Motivated and fully engaged contractor Reliable and experienced 5. Good weather during construction

41 My Thoughts on Warranty

42 Warranty If the five keys towards achieving sustainability in roofing can be meet, then a warranty becomes something to be filed into a drawer and forgotten.

43 Warranty continued Warranties are written to protect the liability of the writer and are not for the benefit of the client. (even though they are perceived to be sold that way.)

44 Warranty continued I m not finished All warranties include exclusion clauses (fine print) that provide an easy out for the warranty provider, and must be carefully considered and understood at the beginning of the process.

45 Let s Talk About: LEED Credit 7.2 Heat Island Effect: Roof Intent Reduce heat islands (thermal gradient differences between developed and underdeveloped areas) to minimize impact on microclimate and human and wildlife habitat.

46 LEED Credit 7.2 requirements Use ENERGY STAR compliant (highly reflective) AND high emissivity roofing (emissivity of at least 0.9 when tested in accordance with ASTM 408) for a minimum of 75% of the roof surface Delburne, Alberta

47 LEED Credit 7.2 Install a green (vegetated) roof of at least 50% of the roof area. Combinations of high albedo and vegetated roof can be used providing they collectively cover 75% of the roof area.

48 Designing to solely earn a LEED point is wrong

49 Practical considerations when thinking about going green with your roof design. White, shiny roofs are very slippery early in the morning and most of winter = Fun for your maintenance crew Dependent upon where you are in Northern Canada, your roof is naturally white from the first snowfall to the end of spring (You don t even have to pay extra for it!) If you get a garden roof make sure it comes with shovels. They will become a critical component, somewhere down the road.

50 Conclusion If roofing design deviates from the Five Keys, in favor of chasing a point, we should all become extremely worried. The shiny plaque at the front door will not keep you dry Adherence to the Five Keys will. So when you are making choices make the one that will last.

51 P.S. I m not against green design, I m for common sense Williams Engineering Canada along side with NAIT and ESAK consulting has proposed Next year, the team will plant a garden on the reinforced roof of the Williams Engineering Canada building in downtown Edmonton

52 Body text goes here

53 Questions and Comments

Roofing Systems. New Applications / Re-Roofing / Maintenance

Roofing Systems. New Applications / Re-Roofing / Maintenance Roofing Systems New Applications / Re-Roofing / Maintenance New Roof Installation In terms of the design and installation of an original roofing system (in conjunction with the construction of a new building),