Air leakage / Guides

Exterior air barrier membrane © Ecohome
Air and vapour barriers

How to install an air barrier for reduced air leakage

...air barrier is to stop air leakage through differences in air pressure between inside and out. A wall system should have one vapour barrier, but can have many air barriers. A vapour barrier can act as a very effective air barrier, but an air barrier does not (and should not) always stop vapour from difusing. Understa...

Air barriers are essential to a properly functioning wall system
Air and vapour barriers

What is an air barrier?

...air barrier as being: 1. Continuous: no gaps, cracks or openings. 2. Impermeable to the leakage of air. 3. Rigid: supported in both directions from wind pressure. 4. Durable: must last the life of the building. 5. Repairable: access for repair if damaged. A sampling of air barrier materials and techniques: ...

Problem areas of air leakage in a home and blower door test being cond
Air and vapour barriers

Airtight Construction of Homes is Essential: "Your house sucks." "Oh yeah? your house blows!"

...Air Tightness in Houses - All about Balancing Air Pressure in the Home We go on incessantly here about the importance of air barriers in home construction to reduce air leakage , but no matter how hard you worked to make a house airtight, if the pressure isn't balanced you will be sucking air in or forcing it out and...

Blower Door Tests - What's the Cost & Who Does Them?
Air and vapour barriers

What is a blower door test? What's the cost? How do you find a company to do one?

...air in from any existing hole in your air barrier no matter how small it is. The operator then determines your ACH (air changes per hour) based on the house dimensions and the volume of air in the home. Standard new home construction in North America seems to return an average air leakage rate of about 3 air changes ...

The difference between air barriers and vapour barriers
Air and vapour barriers

The Difference between air barriers and vapor barriers

...air barriers and vapor barriers The job of a vapor barrier is to prevent vapor diffusion, and the job of an air barrier is to stop air leakage through differences in air pressure. A wall system should have one vapor barrier, but can have many air barriers. A vapor barrier can act as a very effective air barrier, but ...

Wildfire Smoke & How to Keep it Outside Homes
Healthy indoor air quality

How to keep wildfire smoke out of Green Homes with mechanical ventilation systems?

...air. Window air conditioners should not be used during wildfires, unless their outdoor air intake can be closed. A portable air cleaner is recommended to complement air sealing and filtering measures during a wildfire. The air cleaner should have a High Efficiency Particulate Air (HEPA) filter, which blocks 99.97% of...

Interior sheathing as air & vapor barriers in wood frame construction
Air and vapour barriers

Interior sheathing as an air and vapour or vapor barrier

...air seal of a building is measured in ACH (Air Changes per Hour), and is determined by a blower door test where the building is depressurized by a fan in the door, and air leakage is measured. The average home built to code using conventional building practices is expected to have air leakage rates of 3.5 ACH, which ...

Frost in Attics: What causes Attic Ice? How to Fix it?
Roof assemblies - renovation

Why is there frost in my attic? Is ice in roofs a problem & How do I stop it?

...air baffles ensure soffit ventilation works properly © InterNACHI Some builders have expressed concerned that ridge vents aren't sufficient because they can be blocked by snow, but snow isn't an air barrier. It will slow the air, but as long as the vent runs the length of the roof there should be enough air flowing...

Correctly installed Triple pane south facing windows on Ecohome's Demo House
Windows and doors

Installing doors & windows for the best performance in high efficiency homes, LEED & Passive House

...air leakage in homes as well as to save energy. Water leaks from around windows and doors are the visible result of a poor fitting or sealing job, but that's far from where it ends. If there are air leaks from around windows and doors, not only is a home inefficient - ie. It's losing energy - but it's susceptible to co...

Ice dams on roofs & how to fix them
Roof assemblies - renovation

What causes ice dams and how to fix them

...Air leakage through walls : through ceilings is another common problem as a lot of heat is transported by air. This warms the attic and causes that same melting to occur. Ventilation equipment such as furnaces, duct work and air conditioning are rarely seen in attics anymore, but if you have such equipment up there i...

Living green wall
Healthy indoor air quality

Living walls: what they do and don't do

...air quality. Simply due to the rate of air leakage in most buildings, it would be difficult for anything short of an airtight house and a virtual jungle of plants to see a measurable improvement in air quality. However, from a quality of life and design perspective, these make for very cool living rooms. Having potte...