How To Insulate A Metal Garage {5 Options}

Choosing the right insulation for any building can have a huge impact on reducing the amount of energy you use – and can make the building more comfortable to work in. If you’re wondering how to insulate a metal garage, you’re in the right place. 

Does a Metal Garage Need to Be Insulated?

Does a Metal Garage Need to Be Insulated

You may want to skip the insulation on your metal garage as a way to cut costs. It’s true that insulation can sometimes be expensive. However, depending on how you plan to use your garage, insulation might be essential.

Depending on where you live, you might experience serious temperature swings throughout the year. When temperatures vary between the inside and outside condensation (or moisture) can form. 

If your building isn’t properly maintained and insulated, this moisture can cause rust and corrosion while also damaging valuables that you store inside (since it creates mildew and mold).

Insulating your metal building can help to stabilize the interior temperature of the building while also preventing moisture from entering or gathering. 

Not only that, but insulation will allow you to heat and cool your garage more efficiently. That leads to a more comfortable working environment, fewer damaged valuables, and of course, lower heating and cooling costs, too.

Insulation doesn’t necessarily stop heat flow – it slows it down. All materials conduct heat, but metal is the most conductive. 

An insulated metal garage will have a more stable temperature and limited moisture. One final benefit is that it can absorb sound. This is an especially important detail to note if you plan on using your garage as a workstation, or if you want it to block some of the exterior noise from reaching the inside of the rest of your home. 

What is the Best Way to Insulate a Steel Garage?

There are a few ways you can insulate a steel garage. Before you decide, remember that metal is a high conductor of thermal energy (both heat and cool air).

The benefit of a steel garage is that it will be much more durable and stronger than the alternatives – however, you’re probably also going to find that you spend much more on heating and cooling costs if you don’t have good insulation in place.

Therefore, you should consider some of the following insulation options for metal or steel buildings:

Fiberglass Solutions

Fiberglass insulation is one of the most popular insulation solutions for metal buildings because it is the cheapest and easiest to install. You can choose from a variety of solutions to find one that is the most attractive for your garage. 

However, it’s important to note that if you decide to install fiberglass insulation yourself, you’re going to want to wear the right kind of PPE to prevent exposing yourself to carcinogens. 

Spray Foam Insulation

Spray foam insulation can be costly, but it’s one of the best options for insulating a metal garage.

It consists of a polymer that is combined with a foaming agent and then is sprayed into ceiling and wall voids and cavities. Once it’s sprayed, the liquid turns into a solid cellular material containing air-filled cells. These air-filled cells take up every inch of space, even the small ones, so air can’t escape.

If you live in a very cold climate, spray foam insulation is ideal. It not only protects against the cold air that’s trying to get inside, but it also keeps out insect pests and contaminants.

The only downside to spray foam insulation is that the foam can trap moisture – it has no permanence level. The trapped moisture, over time, can rust and corrode away at the underside of the metal panels.

That said, that’s not a reason to forgo spray foam insulation entirely but instead to not try to DIY this project yourself. Instead, you may want to consider hiring an experienced contractor who will use techniques like flashing to prevent this. 

Batt and Blanket

Batt and blanket is another way you can insulate a metal garage. It’s economical and highly effective when done correctly. This is a form of insulation you can apply yourself, but again, for best results, you may want to hire this out. 

Batt and blanket is made out of mineral fiber (usually rock wool or fiberglass) along with a radiant barrier blocking. You can choose a variety of batt and blanket insulation options that vary in their R-value (how well they insulate the garage). 

Usually, batt and blanket are sold in rolls of insulation that you can purchase based on the amount of area that you need to insulate. 

Insulated Metal Panels

This probably won’t be an option if you have already constructed your garage, but if you’re still in the construction phase and looking for tips on how to insulate a metal garage, this is a good option. 

Insulated metal panels can be tough to find, but if they’re available, get them. They can be used both on the interior or exterior and are easy to install. They can be costly, since special equipment is required for installation, but are about as effective as they get. 

Bubble Insulation 

One more option is bubble insulation. This less common method of insulation is made out of polyethylene bubbles. These not only serve as a thermal barrier but they also block condensation.

Steel, as we mentioned, is quite good at trapping and conducting heat. Metal buildings naturally transfer heat energy in and out, but bubble insulation can solve this problem. This kind of insulation reflects radiant heat keeping the temperature off of the steel panels.

Bubble insulation is usually sold based on its perm rating – if it’s less than 1.0, it’s usually considered a full vapor barrier. This is the best at preventing moisture, since it can’t pass through the insulation and get to the steel panels where it creates condensation.

This is one of the best types of insulation if you’re concerned about humidity. It prevents interior commendation and blocks about 96% of radiant heat transfer. Plus, it won’t promote the growth of mold and mildew. 

How Do You Insulate an Existing Metal Garage?

How Do You Insulate an Existing Metal Garage

Any of the building solutions offered above can be used on an existing metal garage – with the exception of metal panels of course. 

However, some will be easier to install once the garage has already been built than others. Of all the options out there, spray foam insulation is perhaps the easiest to install on an already-existing metal building. 

Remember, insulation isn’t always necessary for metal buildings – but you’ll never go wrong by adding some. Consider these tips for how to insulate a metal garage – and you’ll be able to work in your garage in comfort and style

2 thoughts on “How To Insulate A Metal Garage {5 Options}”

  1. Russell,

    A metal garage has been a good material for our uses. If possible, you should choose to stop telling people your opinion, as if it were fact. Also, sentences end with a “.”



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