What are some tips for passing a blower door test?

Tips for passing a blower door test focus on comprehensive air sealing before the test, since the test measures air leakage at 50 pascals and code requires typically less than 3 to 5 air changes per hour depending on state. Start with attic air sealing, which is biggest leak area, seal top plates, plumbing and electrical penetrations, recessed light boxes, and attic hatch with caulk and foam. Seal basement rim joists with rigid foam and spray foam. Caulk bottom plates, window and door framing, and all penetrations through exterior walls. Install quality weatherstripping and door sweeps on exterior doors, ensure windows latch tightly. Seal ductwork with mastic, especially ducts in attic and crawlspace. Seal electrical outlets and switch boxes on exterior walls with foam gaskets. Use airtight recessed can lights rated ICAT. Ensure continuous air barrier like drywall is sealed, use spray foam around windows instead of fiberglass. Close fireplace dampers and seal. Test early with your own blower door if possible to find leaks using infrared or smoke pencil. Do not run exhaust fans during test. Proper sequencing matters, air seal before insulation, and use blower door as diagnostic tool during construction rather than only final test.