Why weatherproofing your garage matters

Small gaps under a garage door allow wind‑driven rain, draughts and debris to enter, leading to damp patches, rust on tools and an uncomfortably cold space. A quality threshold seal and insulation kit will block water ingress, cut draughts, reduce blown‑in leaves and dust, and help keep your garage warmer in winter. Simple solutions that work – and you can fit them yourself. We’re here to help.

1) Stop water coming under your garage door

Fit a PVC threshold seal for a watertight barrier

A garage door threshold seal bonds to the floor and creates a raised lip the door closes against, blocking wind‑driven rain and standing water up to the seal’s height. GaraDry PVC seals are available in multiple heights to suit your gap and exposure levels, and they are designed for common door types including up‑and‑over, sectional, roller‑shutter and side‑hinged.

Expert insight: If you can measure and cut, you can fit it. The flexible PVC helps form a tight seal even on older, slightly uneven concrete floors, reducing leaks and draughts with one straightforward install.

 

2) Choose the right seal height and length

Measure the largest gap between the bottom of the door and the floor in several places, then select a seal height that meets or slightly exceeds that gap for reliable contact. Typical options range from 15–50 mm for domestic garages. Seals are supplied in long lengths and can be trimmed to size with a hacksaw or sharp knife to fit your opening precisely.

• 15 mm – light rain and dust protection
• 25–30 mm – standard UK weather protection for most homes
• 40–50 mm – flood‑prone sites or sloped driveways

GaraDry PVC seals are offered in complete lengths up to 6.17 m for domestic doors; aluminium commercial thresholds use interlocking sections with continuous bottom seals for a full‑length seal.

3) Weatherproofing an uneven garage floor

Uneven floors are a common cause of leaks. Flexible PVC compresses to accommodate small variations and still form a tight seal. For larger dips or undulations, clean thoroughly and apply clear sealant beneath the threshold to level minor troughs before fixing. On severely uneven floors, consider remedial levelling for best results.

If your garage or site involves heavy traffic (e.g. pallet trucks, forklifts, vans), consider aluminium commercial door thresholds secured with fixings into sound concrete; these are designed for industrial environments and continuous use.

4) Stop draughts, leaves and mice entering

A properly fitted threshold seal blocks draughts and blown debris, keeping the space cleaner and more comfortable. The raised profile also acts as a physical barrier to pests such as mice. For doors with open side tracks (common on sectional and roller doors), add foam side blocks to close gaps beside the tracks for a continuous seal.

5) How to insulate a garage door for winter

A threshold seal stops water and draughts at floor level; pair it with a garage door insulation kit to reduce heat loss through thin steel door panels. Cut foil‑backed panels to size and fit them to each panel of an up‑and‑over or sectional door following the kit instructions. Combined, these upgrades can help keep your garage more stable in temperature and more comfortable to use in cold months.

6) Extra protection for flood‑prone driveways

If you regularly see standing water against the door or your driveway slopes towards the garage, consider a higher‑profile (e.g. 50 mm) threshold to resist deeper water at the entrance. For severe conditions, pair a threshold with additional flood defence products for a layered approach.

7) DIY fitting – quick steps for a lasting seal

You can install a GaraDry PVC threshold in under an hour with basic tools. Follow these steps for a clean, durable bond:

1. Prepare the area: Clean thoroughly and remove dust, oil and loose paint. If epoxy or tiles are very smooth, lightly dull the surface and remove all residue.
2. Measure & mark: With the door closed, position the seal behind the door and mark the outline. Notch around frames or tracks so it sits tight to the back of the door.
3. Cut to size: Trim with a hacksaw or sharp knife.
4. Adhesive pattern: Apply two parallel lines with an unbroken zigzag between them inside your guide marks.
5. Place & press: Set the seal into the adhesive and press down firmly along the full length. Wipe away any excess.
6. Seal the ends: Apply adhesive around frames and ends to ensure a watertight finish; add side blocks if you have open tracks.
7. Cure time: Allow 24 hours before driving over; test with a bucket or hose after curing. Recommended application temperature: 5 °C to 35 °C.

Expert insight: Surface suitability: Install only on sound floors (not loose concrete or gravel). Unsealed, dusty concrete should be sealed before fitting to ensure proper adhesion.

 

8) Care and maintenance

• Wipe clean with a damp cloth – avoid harsh chemicals and pressure washers.
• Drive slowly over the threshold; it is a seal, not a speed ramp.
• Check the bond annually, especially if the floor surface changes or cracks.

For domestic vehicles, PVC thresholds are suitable for most day‑to‑day use; for frequent heavy vehicles, consider aluminium commercial thresholds.

FAQs

Helpful resources

• How to measure for a garage door threshold seal
• Garage door threshold seals
• Garage door insulation kits
• Flood barrier thresholds
• Customer gallery – real installations