Roofing, Flashing, and Attic Ventilation

1. Roofing, Flashing, and Attic Ventilation WEATHERIZATION INSTALLER/TECHNICIAN FUNDAMENTALS WEATHERIZATION ASSISTANCE PROGRAM STANDARDIZED CURRICULUM – July 2012

2. Learning Objectives By attending this session, participants will be able to: Name required fall protection components. Identify and repair leak sources. Remove roofing systems. Insulate roof decks. Explain the purpose and principles of attic ventilation. Determine ventilation needs by code and practical alternatives. List ventilation options and guidelines. Install attic ventilation and repair roofing. Flash new penetrations.

3. Fall Protection Proper fall protection can mean the difference between this… Image courtesy of lawlessgroup.com Image courtesy of www.fallprotectionplans.com …and this.

4. Where do we fall from? Breakdown of fatal falls in 2009 Chart courtesy of U.S. Bureau of Labor Statistics, U.S. Department of Labor, 2010.

5. Personal Fall Arrest Systems A personal fall arrest system (PFAS) must include these components: • Anchorage • Body Harness • Connector/lanyard • A PFAS may also include a deceleration device and/or lifeline. Image courtesy of Kentuckiana Industrial Safety Training

6. Typical Roofing System Components Image courtesy of national-roofers.com

7. Creating a Drainage Plane Note flashing locations at every edge. Image courtesy of livingsmarter.org

8. Flashing Materials Image courtesy of diyadvice.com

9. Common Fasteners Image courtesy of diyadvice.com

10. Removing Old Roofing Install roof jacks to prevent debris from littering the area. Cover surrounding landscaping with tarps to ease cleanup. Images courtesy of familyhandyman.com

11. Purpose of Attic Ventilation • Removes solar heat during hot weather. • Removes moisture vapor during cold weather. Photo courtesy of US Department of Energy

12. Common Misconceptions • Attic ventilation always removes moisture vapor during cold weather. • Attic ventilation will cure an attic moisture problem. • The more attic ventilation, the better. • Attic ventilation is not necessary.

13. Post Wx Attic Moisture Problems Mold on Sheathing Frost on Sheathing Photos courtesy of US Department of Energy Both conditions occurred after attics were insulated and vented, not before.

14. Passive Attic Venting: Convection Ridge Vent How does it work? Outlet (Heated Air) • Natural Convection • Hot air rises, escapes high vents. • Cooler air is pulled through soffit vents. • Heat rises, escapes ridge vents. Inlet (Cool Air) Graphic developed for the US DOE WAP Standardized Curricula

15. Passive Attic Venting: Wind WIND How does it work? • Bernoulli Principle • Positive pressure on windward side • Negative pressure on leeward (protected) side • Air is sucked out leeward vents Graphic developed for the US DOE WAP Standardized Curricula

16. Power Venting Fan-Powered Roof Vent How does it work? • Attic fan mounted in central hallway used in non-air-conditioned homes • Roof vent (pictured) used in air-conditioned homes • Neither is recommended as a weatherization measure. • Potential for moisture condensation is high. Graphic developed for the US DOE WAP Standardized Curricula

17. Code Issues Thermal Boundary - Ceiling Based on presence of ceiling vapor retarder No vapor barrier: 1/150 One square foot of net free vent area per 150 square feet of attic. Vapor barrier: 1/300 One square foot of net free vent area per 300 square feet of attic. Graphic developed for the US DOE WAP Standardized Curricula

18. Code Issues Thermal Boundary - Roof Deck Attic ventilation is not required when roof assembly is the thermal and pressure boundary. Graphic developed for the US DOE WAP Standardized Curricula

19. Insulating the Roof Deck Insulating the roof deck brings the entire attic into the conditioned space. This is beneficial where ducts and pipes run through the attic. Shown here, spray foam has been applied to the roof deck. Rigid board and fiberglass are also used on roof decks. Photo courtesy of Home Energy Magazine

20. Ground Rules and Specifications • Vented attics should not communicate with the conditioned space. • The ceiling air barrier must be continuous with no leakage. • Specify appropriate attic sealing as part of the work scope. • Specify that vents be placed low and high on roof. • Specify eave chutes when soffit vents are present and loose fill insulation is needed. • Specify that all mechanical ventilation ducts and plumbing stacks are vented directly to the outside.

21. Venting Configurations In a perfect world… Continuous Ridge Vent Continuous Eave Vent (Soffit Vents) Graphic developed for the US DOE WAP Standardized Curricula

22. Vent Types Gable Vent Roof Vent Eave Vent Images courtesy of J&R Products Inc.

23. Vent Types Turbine Vent R-144 Mushroom Roof Vent Images courtesy of J&R Products Inc.

24. Vent Placement Roof vents placed high on roof Continuous Soffit Vent Photo courtesy of PA WTC

25. Vent Installation • Cut hole to fit; test fit vent. • Caulk edges of hole where flange will sit. • Slide vent into place under shingles. • Seal and nail. Photo courtesy of the US Department of Energy

26. Vent Placement Gable vents are attached similarly to roof vents. Photos courtesy of the U.S. Department of Energy

27. Attic Window Vent Photo courtesy of the US Department of Energy

28. Eave Chutes Eave Chute Photo courtesy of PA WTC; Product photo by J&R Products, Inc.

29. Mechanical Vent Terminations Photo courtesy of PA WTC

30. Summary Use proper fall protection when working on roofs. Leaks are most common at flashing. Re-create a quality drainage plain to repair. Attic ventilation is intended to remove solar heat during hot weather and water vapor during cold weather. Attic ventilation is required by code, but expert opinions vary on the actual value. Insulated roof decks bring the attic into the conditioned space and should not have attic venting. Any new penetrations through the roof must be properly flashed.