< How to Insulate a Garage Cheaply. - Garagexpart

How to Insulate a Garage Cheaply.

Any driver knows that garage insulation is not a whim, but a real necessity. If you value your car, you cannot do it without this method. But our world is so organized that there is not always sufficient money for expensive heaters and hiring professionals.

If a garage is not primarily used as a parking space for a used vehicle continuously, insulation and thermal insulation can bring advantages for use. For example, this applies when the garage is used as a hobby room, workshop, and basement replacement or as a permanent garage for a vintage car. Frost-free and a warm interior are then desired, and insulation should ensure that.

The article targets simple drivers who, for various reasons, are forced to install cheap garage insulation with their own hands. I will talk about three insulation options available and the materials suitable for that.

Metal structures on the outside are practically impossible to equip. The most common reason, internal insulation is cheaper. Besides, it is merely physically unrealistic to insulate the ceiling and floor from the outside.

Before you start working, you still need to plan how to insulate the garage.

  • Cleaning of the surfaces.

The surfaces on which the insulation materials are applied should be clean, level, free of dust and grease, and dry so that the assembly adhesive and mortar stick well. Therefore, clean the relevant surfaces before applying the insulation: garage doors made of sheet metal should be washed with water and washing-up liquid; walls and ceilings can be swept down with a broom or vacuumed with a vacuum cleaner to remove dust and cobwebs or the like.

  • Life-saving ventilation

The first step to defeating condensation and corrosion is installing ventilation in your garage. In opposite corners of the garage, two pipes must be brought out.

Place the bottom edge of one of them closer to the floor. Cold air will enter the room through this pipe. A short pipe near the ceiling in the other corner will serve as a fume hood.

This simple but reliable device will work flawlessly automatically, without fashionable fans, creating a natural movement (convection) of air in the garage.

Convection will prevent condensation from forming. Wet vapors will escape into the pipe. Exhaust gases hazardous to health, fuel fumes, and other chemicals stored in the garage will also go there. But now we turn to the most important thing – we insulate the garage with our own hands. Here the situation is more complicated, but the task is quite accessible for an independent solution.

  • Selection of materials

What materials will you have to choose to insulate the garage cheaply? Each material has its subtleties of installation, and, most essentially, the cost of all these materials is different. The Shortlist of thermal insulation materials used in the insulation of garages and their general characteristics check below.

Dense plates of mineral wool

It is an inexpensive material with desirable thermal conductivity parameters with exceptional vapor permeability ideal for garage insulation. The cotton slabs are suitable for your absolute fire safety. Although cotton plates can accumulate moisture, this indicator is not so high for them.

Glass wool and other types of soft, mineral-based rugs

In terms of cost, soft carpets are one of the most affordable heaters.  You will find many photos and video material on the net, where colors count of such rugs.

These rugs quickly gain moisture and can no longer be restored; after 2 to 3 years, they will look like an old bicycle blanket; so think about whether you need those savings.


Among cheap heaters, foam boards are the best option, especially for a garage. The price for this is more than affordable; it does not pass or absorb water. They are easy to mold and cut

Based on my expert opinion, I can guarantee that installing the foam with my own hands is the easiest. Besides, this material is suitable for block and metal structures.

Extruded polystyrene foam

The extruded polystyrene foam contains the same composition as Styrofoam. But these boards are much more durable and stable. In almost all aspects, extruded polystyrene foam is far much better than the old Styrofoam. Only one terrible thing, this material will cost at least twice as much as polystyrene.

Expanded polystyrene

This type of insulation is a derivative of foam, their characteristics are very similar, but there are significant differences: Much denser than polystyrene; It is heavier in weight when insulating the roof with this material, a sheathing device is required; Does not absorb moisture; In terms of price category, it is inferior to polystyrene. Manufacturers also offer materials such as glass wool and mineral wool for insulation.

Soft roll insulation with sheet coating

As a rule, foamed polyethylene, better known as, is taken as a base here. The sheet forms a film to one or both sides of the insulating material. On average, the thickness of the band varies from 3 to 4, up to 20 mm.

Hot plaster

There are several varieties of hot plaster, but the layout principle is the same everywhere. For example, some loose porous material, expanded clay sand, perlite, or foam balls, are mixed into the solution as the main filler and plastering of walls. This insulation is not expensive, but plasterer skills are indispensable here; therefore, not everyone can do it with their own hands.

Expanded clay-

Expanded clay is a porous clay ball obtained by burning particular types of clay. The price of this heater is small, but it can insulate only the floor in the garage.


The chemical composition, penoizole, is liquid foam. Since the material is liquid and only requires spaying, it is easier to work with, but this insulation will cost several times more than the foam arrangement.

Polyurethane foam

The fact is that, in our case, it fits less than the others. Not only is this liquid insulation expensive, but you still need to hire experts for the application. It is not realistic to manage yourself here; you need costly special equipment.


Suppose we analyze all of the above options for compliance with price/quality/ease of insulating a garage. In that case, lead is foam, followed by mineral wool plates and materials made from hot plaster to close these honorable three. Expanded clay; among cheap heaters, it is more suitable for floors.

Expanded polystyrene became almost universal insulation; you can insulate a garage with your own hands; in addition to the reasonable price, this insulation has other advantages: Ease, which is very convenient during installation; Moisture resistance, which avoids high humidity in the garage;

Effortlessly cut to any size with a hacksaw, Diversified in mounting options (using a frame, glue, self-tapping screws); Not susceptible to atmospheric factors, does not change its original properties over time; Possesses bacteriological resistance.

Thanks to modern manufacturers and various building materials in the distribution network, it will not be challenging to complete this task. You have to choose the best option and insulate your garage cheaply.

The materials used to insulate the garage must meet fire resistance requirements, water resistance, and be lightweight for ease of installation. But for many car enthusiasts, it is crucial to insulate the garage cheaply.

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My name is Mike Thorne, a car enthusiast and a DIY for life person. I love spending time in my garage and that is why you will get firsthand information on this blog about all things garage-related.

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