Moisture Control

Moisture is the cause of many home failures, thus controlling moisture crucial to ensuring durability. Excessive moisture causes structural damage and and mold growth, which can lead to heath problems. It is important for building professionals to understand the physical properties of water. Snow and rain are not the only ways moisture can get into a home. Gravitational flow, capillary suction, vapor diffusion, air transport, all are ways water can penetrate a building and it’s roof and wall cavities. To protect a home from moisture, one must understand water in ALL it’s forms-- rain, snow, ice, surface water, groundwater, and water vapor.


Rain, Snow & Ice Protection-

  1. •Proper housewrap and roofing underlayment

  2. •Ice and water shield at the roof’s eaves, valleys, edges, ridges

  3. •Roof AND wall penetration flashings- flashings are not just for roofs (wall penetrations should be flashed as well)

  4. •Highest quality windows and doors

  5. •Generous roof overhangs

  6. •Kick-out flashings

  7. •Rain screen/back-venting exterior claddings


Ground Water & Surface Water Protection

  1. •Swales and other diversion methods

  2. •Perimeter foundation drainage system

  3. •Finish grade sloped away from the building

  4. •Waterproofing/drainage board- foundation walls

  5. •Moisture barrier- underneath foundation slab/floor

  6. •Capillary breaks between foundation and wood framed walls


  7. Water Vapor Control

  8. •Exterior air barrier- Housewrap/sheathing tapped and sealed

  9. •Interior air barrier- Airtight Drywall Approach

  10. •Spray foam sealing, caulk

  11. •Air-tight recessed lighting

  12. •Assessing the vapor profile of wall and roof assemblies


Interior Moisture Removal

  1. •Kitchen and bathroom exhaust fans

  2. •Whole-house mechanical ventilation systems


    2. Durable Materials

  3. •Cement board/fiberglass faced drywall (instead of paper faced drywall) in showers, baths, and basements

  4. •Durable flooring finishes in bathrooms, kitchens, laundry rooms, and entrances.

  5. •Weather-resistant exterior finishes

BUILDING SCIENCE

Moisture Control

Airflow Control

Thermal Control