How to insulate the garage door?

The garage door is a practical element, even today aesthetic, but which, by itself, does not provide the necessary thermal insulation to the garage. However, it is a room that should not be neglected, firstly because it often acts as an airlock between the house and the outside, but also because the garage is increasingly becoming a storage room. than an annex to park a vehicle. It is therefore recommended to insulate it well for optimal comfort.

What types of insulation should you consider?

In order to avoid heat loss, several types of insulation exist. Whether they are bio-sourced, synthetic or mineral, each one carries interesting virtues.

Polyurethane or polystyrene foam sheets

Part of the category of synthetic polymeric insulation, it is actually plastic worked in different forms. It is the most commonly used insulation.


Both polyurethane and polystyrene have notable qualities: economical, perfectly waterproof, weather-resistant, very light, high thermal insulation power. If they both offer similar capacities, polyurethane will remain preferable to polystyrene in terms of efficiency, which will obviously be felt on its price where we will go from simple to triple.


Non-recyclable and made from non-renewable resources, they are not ecological. In addition, if their thermal insulation capacity is excellent, the sound is much less, which can be problematic depending on the use made of the garage. Finally, these materials are strong fuels and release harmful gases if they catch fire.

Plates of wool or wood fiber

As we know, wood is one of the best natural insulators, offering a high level of thermal and sound performance. The difference between wood wool and wood fiber is their manufacturing process.

The wood wool plate is flexible or semi-rigid. It consists of crushed wood fibers, dried, fireproof, then agglomerated with polyester.

The wood fiber board is rigid and is obtained by recovering the waste resulting from the transformation of wood which is mixed either with water or with glue.

These two types of plates are often complementary. For the garage door, we prefer the rigid wood fiber board, but both can be used. These materials are heavier than plastic-based materials, but more efficient and moisture-absorbing, which cleans the garage atmosphere.

Cork sheets

Composed of cork bark residues, this makes it a 100% natural insulator. In addition to its eco-responsible aspect, it has the advantage of excellent thermal and sound insulation. It has the power to retain heat and diffuse it inside.

Thermo-reflective film

It is probably the least effective insulator on the list. It will be preferred on overhead garage doors which will not support too great a load.

And the garage door: insulating material?

These different insulators will in particular be chosen according to the material of your garage door. Indeed, some materials have a natural insulating power while others, conversely, are powerful conductors of temperature.

  • Prison is an extremely conductive material, which makes it almost ineffective in terms of insulation since it will communicate both the extreme cold of winter and the scorching heat of summer. A powerful thermal insulator will therefore be necessary;
  • Wood is an excellent natural insulator. A wooden door will eventually need a simple insulation reinforcement of the lightest possible, but here it will be more a question of obstructing the openings between the door and the ground with a weatherstripping;
  • Metal or PVC are the most modern materials found almost systematically on recent constructions. Often already equipped with insulation, PVC or metal garage doors offer good load resistance, which will allow them to withstand any type of additional insulation.

Also, depending on whether it is tilting, folding, sectional, hinged or rolling, the choice of insulating material will be constrained by the format of the garage door.

Additional tips

Here are three tips for a perfectly insulated door over time.

Installation of weatherstripping

Also to limit heat loss, it is possible to add a weatherstripping to your garage door which will block the air between the door and its frame. It consists of two parts of plastic or aluminum surrounded by rubber: one under the door to seal the threshold, and the other along the sliding panels to finish insulating it. On recent door models it is usually included.

The interview

The lifespan of any appliance or material will depend on the cleaning and regular maintenance given to it. Same principle for the garage door, whose rubber cushions, plastic bands or seals will wear out over time, first by friction obviously, but also by bad weather and sunlight and moonlight . It will be necessary to renew them when a path of air is felt again.

Call a professional

The most handyman will know how to do it with the materials of the trade and perhaps the pair of arms of a charitable soul. For the more amateurs, it would be better to call on a company competent in energy renovation, ideally a craftsman certified RGE (Recognized Guarantor of the Environment), a pledge of expertise in the sector.