~Moisture Control & Ventilation Strategies

This training will cover the DOE-required ASHRAE 62.2 Ventilation Standard (Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings).

Tighter houses require a strong understanding of moisture sources and their control in order to minimize potential for mold and building durability problems. In this session participants will learn the relative strength of various moisture sources and moisture movement mechanisms.

This session will also explore how to determine ventilation needs of a building using estimates of natural air-change, and pressure diagnostics. Exhaust only, heat recovery ventilators, balanced ventilation, and combination heating/ventilation systems will be addressed.

Learning Objectives: 

  1. Understand the health and durability issues associated with moisture in buildings.
  1. Know the most common and largest moisture sources in residential housing.
  1. Understand moisture movement (liquid flow, capillary draw, air movement, and vapor diffusion).
  1. Be able to explain how to control or eliminate various types of moisture sources and/or moisture movement in residential housing: fix leaks, install ground cover, vapor barrier, air barrier, warm up condensing surfaces, lower %RH, sill seal, water proof foundation etc.
  1. Understand the limits of natural ventilation (sometimes too little, sometimes excessive).
  1. Be able to measure tightness of the house using single point blower door test and record as cfm50.
  1. Relate measured cfm50 to recommended ventilation levels established by ASHRAE standard 62.89 (15cfm/person or .35ach/hr).
  1. Calculate Building Airflow Standard (BAS) aka Minimum Ventilation Level (MVL) and Building Tightness Limit (BTL).
  1. Understand sizing method established for ventilation by ASHRAE 62.2 in new construction.
  1. Learn the different types and appropriate use of source and whole house ventilation: exhaust only, balanced, heat and energy recovery systems.
  1. Know the relative installed cost and operating cost of various ventilation systems.
  1. Understand the critical components effecting airflow: duct size, configuration, and termination.
  1. Understand best practices for occupant acceptance: simple control strategies, low vibration, low noise, low energy use, low maintenance.
  1. Understand the various methods used to measure performance and airflow of ventilation systems.

Required Tests: 

  1. Single point blower door
  2. Exhaust flow measurement using pressure pan

Prerequisites: none

Materials: please bring a calculator


Cost: $550 (General Public); $275 (Contractors Associated with a WA State Wx Agency); $0 (WA State Wx Agency Staff)

Instructor: varies - see scheduled course description

Location: Olympia, WA

Registration URL:  Event Link

Date: Jul 12 2011

End Date: Aug 16 2011