If you’re looking for a contractor to build you a new house, you’ll need to have a conversation about airtightness. If you are lucky, your contractor will tell you, “For the last 10 years I’ve tested every home I’ve built with a blower door. Our homes regularly achieve our in-house target of 2 ach50 or lower.” That’s the type of contractor you’re probably interested in hiring.

If you’re unlucky, however, your contractor might say something like this: “None of the builders in our county are required to conduct a blower-door test, because our local code inspectors don’t pay attention to airtightness. So if I were you, I wouldn’t worry about that.”

If you get an answer between these two extremes, you still might be nervous about hiring a contractor whose airtightness philosophy is somewhere in that broad gray area. So what should you do?

Finding a contractor who cares about energy efficiency

This article is the third in a series that tries to help those looking for a competent contractor. Here are links to the first two articles in the series:

• “I Can’t Find a Contractor to Do That”
• How to Talk to Contractors About Exterior Insulation

Once you’ve reviewed the advice provided in those articles, you’ll be ready to tackle the question “What can I do to ensure that my contractor pays close attention to airtightness?”

First, get educated

Before talking to contractors, it’s good to know as much as you can about the following:

• Local building code requirements, and how (or if) these requirements are enforced
• The basic facts about blower-door tests
• The typical leakage points that contribute to airtightness problems

Armed with this knowledge, you’ll be more prepared to talk to your contractor about airtightness. That…