Job guides / Whole home / Weatherization / Fix Drafty Windows
The Job Guide

Stop window drafts, for the price of a pizza.

The short answerTo fix drafty windows, find the leaks with a candle or incense stick on a windy day. Caulk gaps where the interior trim meets the wall and the frame, apply foam or V-strip weatherstripping where the sash meets the frame, and make sure the sash lock pulls the windows tight. For the coldest windows, add a shrink-film insulation kit for the winter. Most windows take 15–30 minutes each.

Leaky windows are one of the biggest sources of drafts. Before you price replacements, these fixes seal most of the air for a few dollars per window.

DifficultyEasy
Time15–30 minper window
DIY costFrom ~$5 / windowestimate
Hiring a proVaries by areaestimate

DIY range is the Home Depot price of the parts below as of Oct 14, 2026 (caulk; caulk gun, foam tape and film kit from Amazon not priced). We didn't find a reliable published pro rate, so none is shown.

Fix Drafty Windows
6 stepsEvery pick rated about 4.5★ or higher, from hundreds to thousands of reviews.
Photo: Mark Rabe on Unsplash
Your Match

The kit, vetted.

Tick items off as you shop. Ratings and review counts were checked on 2026-10-14. Home Depot prices are as of 2026-10-14. Amazon shows its price at checkout.

Tools

2 items
WORKPRO Caulking Gun, 9:1 / 18:1 thrust
Top PickCaulk gun

WORKPRO Caulking Gun, 9:1 / 18:1 thrust

Smooth, dripless-style feed with two thrust ratios.

Amazon 4.6 (3,443)Check price→
Affiliate link placeholder · Home Depot prices as of 2026-10-14 · Amazon prices shown at checkout
Husky 15-in-1 Painter's Multi-Tool (91004)
Top PickScraper

Husky 15-in-1 Painter's Multi-Tool (91004)

Scrapes, opens cans, cleans rollers, and digs out old caulk.

Home Depot 4.8 (781)$6.98View →
Affiliate link placeholder · Home Depot prices as of 2026-10-14 · Amazon prices shown at checkout

Materials

3 items
DAP Alex Plus Acrylic Latex Caulk Plus Silicone, White
Top PickCaulk

DAP Alex Plus Acrylic Latex Caulk Plus Silicone, White

Paintable, easy cleanup. For trim, casings and stationary gaps.

Home Depot 4.6 (10,630)$4.18View →
Affiliate link placeholder · Home Depot prices as of 2026-10-14 · Amazon prices shown at checkout
Frost King R734H Sponge Rubber Foam Tape, 3/4" x 10'
Top PickWeatherstrip

Frost King R734H Sponge Rubber Foam Tape, 3/4" x 10'

Self-stick foam for gaps on doors and window sashes.

Amazon 4.5 (5,111)Check price→
Affiliate link placeholder · Home Depot prices as of 2026-10-14 · Amazon prices shown at checkout
Duck Window Insulation Kit, fits up to 10 windows
Coldest roomsFilm kit

Duck Window Insulation Kit, fits up to 10 windows

Clear shrink film that seals the whole window for the winter.

Amazon 4.5 (5,814)Check price→
Affiliate link placeholder · Home Depot prices as of 2026-10-14 · Amazon prices shown at checkout
The Method

Step by step, start to finish.

  1. 01

    Find leaks

    On a windy day, move a lit incense stick around the trim, sash and lock. Where the smoke wavers, air is leaking.

  2. 02

    Scrape old caulk

    Remove cracked caulk from interior trim joints with the multi-tool.

  3. 03

    Caulk the trim

    Run a bead where the casing meets the wall and the frame, then smooth it.

  4. 04

    Weatherstrip the sash

    Apply foam tape where the sash closes against the frame, and at the meeting rail on double-hungs.

  5. 05

    Lock it

    Latch the sash lock. It pulls the sashes together and closes the gap.

  6. 06

    Film (optional)

    For the worst windows, tape on shrink film and tighten it with a hair dryer.

Watch First

See it done, then do it.

Our picks of the clearest tutorials. Credit and copyright belong to the creators.

This Old House

Window Air Sealing Techniques | Ask This Old House

Finding and sealing window leaks.

Visit channel ↗
Everyday Workbench

Drafty window solutions, How to Insulate Windows and Using Caulk Cord and Rope Caulk on your windows

Budget fixes compared side by side.

Visit channel ↗
Prefer to read?
Drafty Windows? Try These 12 Solutions for Every Budget, from Bob Vila
Read the guide ↗
Good Questions

Before you start.

Caulk or weatherstripping?

Caulk for parts that don't move (trim, frame). Weatherstripping for parts that do (sash edges).

Do window film kits really work?

Yes, for winter. The trapped air layer cuts drafts and condensation. Remove it in spring.

When is it time to replace?

When frames are rotted, sashes won't stay open, or the glass seal has failed (fogging between panes).

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