Blower door test cost

A blower door test measures how much air your house leaks. The auditor sets a fan in an outside door, pulls air out of the house and reads the airflow at a fixed pressure. That reading is called CFM50.

What it costs in the Denver area

• Inside Xcel's Squad Plus visit: $100 for a limited time, normally $150, for eligible Xcel customers, with infrared and a safety test included.
• Inside an independent audit: two Denver auditors list $335 (REenergizeCO) and $375 (EnergySetter). Xcel pays back 60%, up to $160 for an audit with a blower door or $200 with infrared, so Xcel gas customers pay $135 to $175 in the end. With Xcel electric and other heat the cap is $160, so $175 to $215. Without the rebate, it's the full price.
• On its own: e3 Power in Denver lists single tests from $250. Blower Door Testing of Chaffee County starts at $500 for a blower door and duct test with a report, more for complicated houses or long drives. Xcel's rebate is for audits, so a test by itself gets none.

For an eligible Xcel customer, Squad Plus costs less for the whole visit than e3 Power's test on its own.

When you need it

Xcel's air sealing rebate asks for at least a 20% cut in CFM50 leakage. That takes a reading before the work and another after it, which is why the audit comes first.

When it can't be run

The Squad won't run the test in a home with vermiculite attic insulation or a dirty wood-burning fireplace. EPA says most vermiculite sold in the U.S. until 1990 came from a mine contaminated with asbestos, so treat it as if it holds asbestos and leave it undisturbed. Tell the auditor about it when you book.

Price your own audit in the cost estimator.