Drafts & Windows

How to Find Drafts in Your House: Simple Tests That Actually Work

Drafts are easier to fix when you map where air is moving instead of sealing random gaps. This guide shows simple tests that work in houses and apartments.

Last updated 2026-05-07 | Reviewed for practical home comfort, safety, and source quality

Key takeaways

Drafts often hide at trim, outlets, attic hatches, basement rims, and door sweeps, not just window glass.
Test on a cold or windy day so small leaks are easier to feel.
Match the fix to the leak type: moving parts need weatherstripping; fixed trim gaps need caulk.
Large attic, basement, crawl space, or garage leaks can signal a bigger air-sealing problem.

Draft test snapshot

Time needed20-45 minutes

DifficultyEasy

Best dayCold or windy

ToolsTissue, incense, flashlight, painter tape

Draft testing checklist for windows, doors, outlets, and baseboards

Most common draft locations

Start with windows and exterior doors, but do not stop there. Air often leaks at outlet boxes on exterior walls, baseboards, pipe penetrations, attic hatches, recessed lights below attics, basement rim joists, crawl space openings, and gaps behind trim.

Draft test table

Test	Where to use it	What it shows	Difficulty	Best next fix
Hand test	Window trim, door edges, baseboards	Obvious cold air movement	Easy	Mark the leak and retest with tissue
Tissue test	Supply vents, window seams, outlets	Small moving air leaks	Easy	Weatherstrip moving parts or gasket outlets
Incense test	Trim gaps and suspected leaks	Air direction and subtle drafts	Moderate	Caulk fixed gaps where allowed
Paper test	Doors and operable windows	Weak compression seals	Easy	Replace weatherstripping or adjust latch/lock
Flashlight test	Door sweeps, basement gaps, attic hatch edges	Visible gaps to another space	Easy	Add sweep, hatch weatherstrip, or report large gaps

Hand test

Run your hand slowly around window trim, sash locks, door edges, baseboards, and outlets. A cold surface is not always a leak; moving air is the clue.

Candle or incense test

Use incense instead of an open candle if possible. Hold it near a suspected gap and watch whether the smoke bends or pulses. Keep it away from curtains and never use smoke near a smoke alarm you cannot reset.

Paper test

Close a door or window on a piece of paper. If the paper pulls out with little resistance, the seal may not compress well. Try several spots around the frame.

Flashlight test

At night, have one person shine a flashlight around an exterior door, attic hatch, or basement gap while another person looks from the other side. Light passing through often means air can pass too.

Outlet and switch test

Remove no covers unless you know it is safe. With the cover in place, feel around exterior wall outlets on a windy day. Foam outlet gaskets can help small leaks, but electrical concerns need an electrician.

Window and door test

Check locks, sash alignment, weatherstripping, door sweeps, and the gap between trim and wall. If glass itself feels cold, use the thermal curtains vs window film guide to choose a comfort layer.

Baseboard, attic hatch, and basement checks

Baseboards can hide gaps between flooring and wall framing. Attic hatches often leak because they are not weatherstripped. Basements and crawl spaces can leak around pipes, rim joists, and access doors.

Dwell Calm tip

Use painter tape to label each leak as fixed gap, moving part, outlet, or professional. That small map keeps you from using caulk where weatherstripping belongs.

What to do after finding a draft

Mark each leak with painter's tape and write down whether it is movable, fixed, renter-safe, or professional. Fixed trim gaps may take caulk. Moving parts need weatherstripping. Large attic, garage, or basement leaks may need air sealing and insulation.

Low-cost fixes

Weatherstrip operable windows and doors.
Add a door sweep or draft stopper.
Use removable rope caulk for seasonal window gaps.
Caulk fixed trim gaps where allowed.
Add foam gaskets behind outlet covers on exterior walls.
Weatherstrip attic hatches and report large leaks in rentals.

When a draft means a bigger insulation problem

If a whole wall, floor, or ceiling feels cold, the issue may not be one crack. Rooms over garages, attic-adjacent bedrooms, and basement rooms often need air sealing plus insulation. ENERGY STAR notes that sealing air leaks and adding insulation can improve comfort and reduce energy waste; the important part is finding the leakage path before adding materials.

FAQ

What is the easiest way to find drafts?

Use your hand or a tissue around windows, doors, outlets, baseboards, and attic hatches on a windy or cold day.

Is the candle test safe?

A candle can show air movement, but an incense stick or tissue is safer. Keep smoke or flame away from curtains, insulation, and children.

Why do windows feel drafty with no air leak?

Cold glass can cool nearby air and create a downdraft. That feels like a draft even if the window is sealed.

Should I caulk every gap I find?

No. Caulk fixed trim gaps, not moving window parts, drainage openings, or areas your lease forbids. Use removable options if you rent.

When is a draft a bigger insulation problem?

If large wall sections, floors, attic hatches, or rooms over garages feel cold, the issue may be air sealing and insulation beyond a simple window gap.

Where to start if you only feel a draft

Start with the places where air usually changes direction: window sash corners, exterior door thresholds, outlet plates on exterior walls, baseboards, attic hatches, plumbing penetrations, and basement edges. Test one area at a time and mark confirmed leaks before sealing anything.