How to Spot and Fix Drafts Before They Drive Up Heating Costs this Winter

As temperatures begin to fall and heating systems switch into full-time use, many homeowners start noticing cold spots creeping into their living spaces. A slight chill near a window, a cool breeze under a door, or cold air descending from the attic can all signal heat loss. These small leaks can have a surprisingly big impact on winter heating costs, forcing your boiler or heat pump to run longer and work harder. Fortunately, most drafts originate from just a few common areas — doors, windows, and attic or roof spaces — and many of the issues can be identified and fixed with simple DIY solutions before calling a professional.

This guide explains why drafts develop, how to identify them, and what you can do yourself to fix the problem while knowing when it’s time to involve an expert.

Why Drafts Develop in These Areas

Drafts appear as materials age, shift, or lose their original tightness. Doors, windows, and attic openings are especially prone to air leaks because they create natural weak points in the structure of the home.

1. Windows

Drafts around windows usually develop due to:

  • Worn or cracked seals
    Rubber and foam seals deteriorate over time from sunlight, fluctuating temperatures, and general aging.

  • Shrinking or warped frames
    Timber frames expand and contract throughout the year, creating gaps that allow cold air to enter.

  • Damaged glazing putty on older windows
    Single-pane windows rely on putty to seal the glass; when it cracks, air slips through.

  • Old or failing caulk
    Exterior caulk eventually breaks down, letting air move around the edges of the frame.

2. Doors

Exterior doors endure constant use and are exposed to the elements, so gaps tend to form over time. Common causes include:

  • Gaps between the door and frame
    Even slight openings around the edges can create noticeable cold spots.

  • Flattened or missing weatherstripping
    High-traffic doors often lose their sealing material much faster than expected.

  • Loose or misaligned hinges
    When hinges loosen, the door may not sit flush with the frame, leading to drafts.

  • Minor frame settling
    Natural settling over the years can shift a frame just enough to let air through.

3. Attics & Roof Spaces

Warm air rises, making the attic one of the most important areas to monitor.

Common issues include:

  • Gaps around the attic hatch or loft door
    These openings are often neglected, leaving large areas unsealed.

  • Gaps around roof-space vents or structural joints
    Small openings in the roof structure can allow air movement between the home and outdoors.

(Note: While insulation is crucial in reducing heat loss, installing or replacing insulation should be handled by a professional.)

How to Identify Drafts

Identifying drafts doesn’t require specialist equipment — just attention and a few simple techniques.

1. The Hand Test

On a cold day, slowly run your hand around:

  • Window frames

  • Door edges

  • The attic hatch

If you feel cold air, you’ve found a leak.

2. The Candle Test

Hold a lit candle near suspected draft points and watch the flame.

  • If it flickers or pulls to one side, air is moving.

This is an easy way to pinpoint exact leak locations.

3. Look for Visual Clues

Drafts often leave subtle signs:

  • Light shining around a door edge

  • Cracked or brittle caulk

  • Worn or flattened weatherstripping

  • Dust trails around attic openings, which indicate airflow

4. Use a Thermal Camera (Optional)

Smartphone-compatible thermal cameras or hireable infrared tools quickly show cold spots and can help identify invisible leaks around frames or in the attic.

DIY Fixes You Can Do Before Calling a Professional

Most draft issues around windows, doors, and attic hatches can be resolved with simple materials and basic tools.

Fixing Window Drafts

1. Replace Weatherstripping

Self-adhesive foam, rubber strips, or V-seals can be used to reseal:

  • Casement windows

  • Sliding windows

  • Single- or double-hung windows

Replace any seals that are cracked, loose, or missing.

2. Re-Caulk Window Frames

Use exterior-grade caulk on outside gaps and silicone on interior joints. This blocks airflow and helps keep window frames airtight.

3. Apply Window Insulation Film

Clear shrink-film insulation creates an extra airtight layer that significantly reduces heat loss, especially helpful for older or single-pane windows.

4. Repair Glazing Putty

If you have older windows with loose or cracked putty:

  • Remove damaged sections

  • Apply fresh glazing compound

  • Smooth and allow to cure

This restores the seal around the glass.

Fixing Door Drafts

1. Fit a Door Sweep

A rubber or brush-style sweep blocks drafts from entering under the door.

2. Replace Weatherstripping

Remove worn weatherstripping and install new materials that fit tightly against the frame.

3. Tighten Hinges and Realign the Door

Loose hinges allow gaps to form. Tightening screws or replacing damaged ones can help the door close snugly again.

4. Use a Temporary Draught Excluder

A fabric draft stopper is a quick and simple fix for colder nights or temporary gaps.

Fixing Drafts Around the Attic Hatch or Loft Door

1. Seal the Hatch with Foam Gasket Tape

Apply foam tape around the perimeter of the hatch to create a tight seal.

2. Add Insulation Board to the Hatch Lid

Attaching insulation board to the back of the attic door reduces heat loss through the opening — a safe DIY improvement that doesn’t involve installing insulation elsewhere.

3. Seal Small Gaps Around Joists or Openings

Use caulk or expanding foam to close any visible cracks around the hatch frame or small roof-space gaps.

When to Call a Professional

You should involve a professional if you notice:

  • Damaged or rotten window frames

  • Significant door misalignment

  • Structural gaps in the attic or roof

  • Condensation or moisture around window frames

  • The need for new insulation or insulation upgrades

Professionals can perform comprehensive assessments and carry out long-lasting repairs that ensure maximum energy efficiency.

Conclusion

Drafts may seem small, but they can cause major heat loss and significantly increase winter heating costs. By focusing on the most common problem areas — windows, doors, and attic or roof spaces — you can identify issues early and complete many of the most effective fixes yourself. Taking these steps before winter sets in will make your home warmer, more comfortable, and more energy-efficient, while reducing the workload on your heating system. And when you encounter larger issues or need insulation upgrades, a professional can help ensure your home is fully protected from the winter chill.