Winter Proof Your Garage: Insulation Tips & The Best Doors

As winter settles across Hampshire, the garage often becomes the coldest room in the house. For many homeowners in Andover and Winchester, a freezing garage isn’t just uncomfortable—it’s a problem.

If your garage is attached to your home, it acts as a giant refrigerator, sucking heat out of your hallway or kitchen. At KJM Group, we find that while the garage door is the biggest opening, it’s part of a wider insulation puzzle.

Modern insulated doors provide the warmth of a brick wall with the convenience of automation.

1. The “Quick Wins” (DIY Fixes)

If you aren’t ready to replace your door just yet, there are a few maintenance tasks that can help take the edge off the chill.

• Check the Floor Seal: If you can see daylight under your garage door, you are losing heat. A rubber threshold seal (bolted to the concrete floor) can stop cold drafts.
• Renew Weather Strips: On older up and over doors, the side seals often perish. Replacing these can reduce the “rattle” and draft.
• Insulation Kits: You can buy foil-backed foam kits to stick onto the back of a metal door. Warning: This adds weight to the door, which may require you to re-tension the springs.

2. The Problem with Single-Skin Doors

Most older homes in the UK have a Single-Skin Steel Up & Over Door. While these are secure and durable, thermally, they are a disaster.

Metal is a conductor. When it is 0°C outside, a thin sheet of steel transfers that cold directly inside. It effectively acts as a radiator working in reverse, cooling your garage down rapidly.

3. The Ultimate Solution: Sectional Garage Doors

If you are serious about warmth, the Garador Premium Sectional Door is the gold standard. Unlike a single piece of metal, these doors are built from 42mm thick panels.

A cross-section of a 42mm sectional panel: Steel skins front and back with a dense foam core.

Why Sectional is Superior for Winter:

1. 42mm Insulation: The panels are filled with PU foam. This gives them a U-value comparable to a brick cavity wall.
2. Sound Insulation: It’s not just about heat. The solid construction dampens traffic noise significantly.
3. All-Round Seals: Sectional doors feature heavy-duty rubber seals on the top, bottom, and both sides. When the door closes, it pushes tight against the frame.

4. Beyond the Door: Roof & Walls

You wouldn’t install a new front door and leave the windows open. The same logic applies to your garage.

The Roof Space (Critical):
Heat rises. If you have a pitched roof with open rafters, installing standard 100mm mineral wool (loft roll) between the joists is an affordable job that makes an immediate difference.

The Walls:
Most garages are built with single-skin brick. Consider building a simple timber stud wall inside the brickwork and filling it with insulation batts, or using insulated plasterboard.

5. Roller vs. Sectional: Which is Warmer?

Both are better than an old Up & Over door, but there is a clear winner for insulation.

6. Frequently Asked Questions