| Summary of Recommendations
ROOF AND CEILING SYSTEMS
Evaluate roof pitch and material properties when selecting roof coverings. (p. 4)
Apply bituminous adhesive taping on sheathing joints, use appropriately rated roof coverings, and fasten coverings per manufacturer instructions in high wind areas. (p. 7)
Use hail-rated shingles and remove old shingles (when re-roofing) in hail-prone regions. (p. 8)
Avoid concentrated or obstructed roof drainage pathways. (p. 8)
Minimize roof penetrations by using selected plumbing and HVAC technologies. (p. 8)
Specify flashing details for roofs, including kick-out flashing and other details, and incorporate in roofing contracts. (p. 10)
Design roof ventilation based on climate and insulation amount to prevent ice dams. (p. 16)
Size eave and rake roof overhangs based on climate. (p. 20)
Design a properly sized roof drainage system including gutter sizing, downspout sizing and downspout placement, based on roof pitch and local rainfall intensity. (p. 21)
WALL SYSTEMS
Consider a drained cavity weather-resistant envelope (WRE) system for most non-severe climates and building exposures, or select alternative WRE approach based on climate, site condition and target performance level. (p. 24)
Follow manufacturer's installation guidelines for windows and doors. (p. 33)
Field test repetitive installations on large projects. (p. 33)
Understand how windows and doors are designed to manage water. (p. 33)
Use third-party certified windows and doors. (p. 34)
Specify and verify wind pressure and impact resistance performance ratings for windows. (p. 34)
Specify flashing details for all windows, doors, and ledgers. (p. 37)
Supplement standard flashing details for additional protection against severe weather. (p. 40)
Specify and use appropriate sealants and installation practices for particular applications. (p. 45)
FOUNDATIONS
Site Planning and Foundation Design
Create a workable site drainage plan prior to construction. (p. 46)
Provide a finished grade away from the foundation greater than the minimum (6" in 10') to offset backfill settlement. (p. 49)
Use a simple screening process to assess sites for moisture and drainage concerns. (p. 49)
Basement Foundations and Basement Walls
Include foundation backfill specifications on plans and in foundation contractor agreement. (p. 51)
Waterproof exterior walls of basements used for storage or living space. (p. 52)
Install horizontal reinforcement at top and bottom of foundation walls to control cracks. (p. 52)
Design basement insulation and finishes to dry towards the interior, especially where traditional finish practices (e.g. warm-in-winter vapor retarder) have resulted in moisture problems. (p. 54)
Use semi-permeable rigid foam insulation between the foundation wall and finished basement walls when using a basement finish system that dries to the interior. (p. 54)
Prevent warm, humid indoor basement air from leaking into finish wall and ceiling assemblies. (p. 54)
Separate basement wall finishes from the basement floor slab. (p. 56)
Slab on Grade
Provide a mounded foundation pad to achieve 8" minimum clearance above exterior finish grade. (p. 57)
Use a sub-slab vapor retarder directly below slabs with a capillary break layer beneath the vapor retarder. (p. 57)
Provide for concrete slab crack control with wire or fiber reinforcement and control joints. (p. 57)
Install horizontal rebar as reinforcement to reduce foundation cracking. (p. 59)
Apply slab foundation insulation on the foundation exterior of slab on grade foundations. (p. 59)
Use moisture resistant finishes on new slabs where feasible. (p. 60)
Use slab insulation strategies when moisture sensitive finishes will be applied. (p. 60)
Account for top-of-slab vapor control before finishing existing slabs that do not have a sub-slab vapor barrier. (p. 60)
Crawl Spaces
Provide a lapped ground cover for all crawlspace foundations. (p. 62)
Provide foundation drainage and damp-proofing for crawlspaces that are below exterior grade. (p. 62)
Evaluate vented and non-vented (particularly for hot/humid climates) crawlspace ventilation strategies. (p. 63)
Wood Framing
Maintain minimum 8" clearances to protect wood from ground moisture. (p. 64)
Match the treatment level of preserved wood to the application and exposure. (p. 67)
Store all treated wood in a protected, ventilated space before use. (p. 69) | 