AIR SEALING
Air leakage wastes energy – in a big way
A typical house continually leaks large amounts of conditioned air to the outside 24/7. Energy Star reports that air leakage accounts for a whopping 25–40% of the energy used for heating and cooling in a typical home.
Let’s put that in to perspective. If 40-50% of a home’s energy is devoted to heating and cooling and 25-40% of that is lost in leakage to the outside then 10-20% of the energy use in a home is wasted by airleakage. The scope of this problem is enormous, especially when multiplied by tens of millions of homes.
Source: 2010 Buildings Energy Data Book, Table 2.1.1 Residential Primary Energy Consumption, by Year and Fuel Type.
Air leakage is a main cause of comfort problems in a home
We’ve all been in a home that has the following problems
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Drafty windows
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Drafty doors
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Hot/cold rooms
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Hot second floors in the summertime
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Cold basements
These problems are all directly caused by air leakage. The following diagram shows where air leakage typically occurs most.
The Solution – A more comfortable home is an air sealed home
A sustainable solution is to build an air tight home in conjunction with appropriate mechanical ventilation. This “green” approach simultaneously solves energy loss problems and comfort problems while providing consistent fresh air throughout living spaces. This kind of comprehensive solutions to complex comfort problems are why high performance homes are higher quality more comfortable homes.
However, building an air tight home is not easy. It takes specifically trained architects performing comprehensive design, thorough project planning, and meticulous construction practices to build an airtight home.
The Concept – The 6 sides of the box should be have a connected air seal
Building an air tight home starts with a basic concept...designing and constructing a connected air tight layer on all 6 sides of a home. It’s the connected concept that is the most critical pieces as it is common to have gaps and cracks at windows and doors.
See the red line? The red line is the air tight layer and includes the ceiling, the connection from the ceiling to the floor, the windows and the connection to the windows, the slab and the connection to the slab...and so on.
The Details – Air tight frame wall with window/door junctions and penetrations
It’s not enough to put house wrap on a home and call it air tight. It takes highly detailed design and consistent, meticulous installation practices to make an air tight home. Check out what makes a True Turtle a higher quality, more comfortable home compared to homes built to code in these details below.
GUT RENOVATION AIR SEALING STRATEGIES AND PRACTICES
Air sealing a 100 year old brick structure is a challenge. We do not use spray foam because of it’s possible health risks. That makes it doubly a challenge. Here is a synopsis of what works.
Keeping the original ceiling here allowed us to build frame walls to that ceiling and not introduce new junctions that need air sealing.
Keeping the ceiling helps keep the original air seal.
Our final PICTURE... Completed home to give our final reported air tightness number for the model
Keeping the original ceiling here allowed us to build frame walls to that ceiling and not introduce new junctions that need air sealing.