Test Out Energy Audit?
What is a "test out" energy audit and why should it be performed?
When you had your energy audit completed the air tightness of your house was tested and an air leakage rate (in cubic feet per minute) was calculated. Generally, energy efficiency improvements including insulation and air sealing will reduce the air leakage of your house thereby making your house more comfortable and saving you money and energy. These are good things.
However, houses can be made too airtight which can in some cases cause problems for atmospherically drafted heaters and water heaters. The house may be too airtight that these combustion systems struggle for air or even backdraft exhaust gas into the house. This is a significant concern due to the potential presence of carbon monoxide and other exhaust gasses.
If you are having insulation and air sealing performed on your house, your contractor or a qualified energy auditor should perform a "test out" audit. This should include a blower door test to determine how successful the air sealing work has been. It should also include a "worst case depresurization test" to check the draft of combustion appliances to make sure the systems have not been adversely affected by the air sealing work.
Additionally, you may find a more airtight house will hold more moisture and for example, the basement which never felt humid before, now feels humid. This is an unfortunate side affect of making the house more airtight. The moisture which entered your basement previously had a way out of the previously leaky house. The new more airtight house now keeps moisture which now must be dealt with. There are ways to address moisture concerns in a house.
Your energy auditor is here to help and will try to answer any questions you have.