Metal Building Insulation Types, Cost + Benefits

When the weather gets chilly and the wind starts blowing, metal building insulation helps make sure you’re comfortable in any kind of metal structure. During winter preparation, you might be wondering if you really need insulation for your metal building, which type of insulation works best, and where to get started.

In this article, we’ll dig into those questions and answer how much insulation costs to install. Once we’re through, you’ll know all you need to make an informed choice for yourself on which type of insulation to choose or whether to use it at all.

4 Insulation Benefits

No matter what kind of metal building you’ve got, insulating it comes with many benefits. It can improve the usability of your metal structure, protect your belongings, and even improve the resale value of your property. Let’s dig into more of the benefits of insulation below.

1. Creates a Moisture Barrier

Moisture control and prevention is the primary purpose of metal building insulation. Metal allows heat to pass through it in a process called thermal bridging. Thermal bridging can lead to condensation from the temperature difference, which can damage metal over time by oxidizing and rusting it. Insulation slows down this temperature transfer, lowering the chance of harmful moisture building up.

2. Regulates the Inside Temperature

Another purpose of insulation is to regulate the temperature inside a building. Insulation blocks heat from escaping in the winter or flowing inside in the summer. This helps to keep your structure warm or cool when it matters most. And if you have a heated garage, you’ll lose money via escaping heat without the proper insulation to keep it in.

3. Absorbs Loud Sounds

Insulation doesn’t just affect temperature. By adding extra padding to your walls, metal building insulation turns down the volume on loud sounds—an extra advantage if you’re insulating a garage, workshop, or shed where you work with heavy or loud machinery.

4. Improves Resale Value

In most cases, a metal structure that has insulation will boost your property’s resale value. For example, a garage adds more property value to your home than a carport because a garage adds storage and square footage in addition to a covered parking space. If that garage has insulation, its potential value and usability increase because it can be enjoyed comfortably throughout the year.

3 Best Metal Building Insulation Types + Sizes and Cost

With so many different kinds of insulation on the market, it can be tricky to decide which type of metal building insulation fits your budget and needs best. Insulation is measured by its R-value, or its ability to resist heat flow—a higher R-value means more protection against the transfer of heat.

Here are the best types of insulation for metal buildings along with their typical cost. (Note that cost figures are subject to change.)

1. Double Bubble

Double bubble insulation has a silver backing that goes against the sheeting on the building. The other side of the insulation (the side you see) is white. Double bubble is used to control moisture. It prevents condensation on the inside surfaces of the building, but it doesn’t provide much temperature control.

• R-value: 1
• Typical cost: $1.50 per square foot

This is the least expensive and least protective type of insulation.

2. Woven

This is a mixture of aluminum foil, bubble material, and woven material, which combine to produce the R17 rating. Woven insulation has a higher R-value rating and is a better option for controlling the temperature in a metal building.

• R-value: 17
• Typical cost: $3.00 per square foot

Woven insulation is often considered the best insulation choice for metal buildings.

3. Spray Foam

Spray foam insulation is a more customizable option because it can be applied in odd shapes and tight spaces at almost any thickness. Spray insulation can either be open cell or closed cell—closed cell means the insulation is water-resistant and can be used in places with likely water contact. Closed cell spray insulation is also significantly more expensive than open cell.

• R-value (open cell, per inch of foam): 3.8
• R-value (closed cell, per inch of foam): 7
• Typical cost: $2.30–$7.20

Spray foam insulation isn’t recommended for metal buildings in very wet or humid climates because it can allow moisture from inside the building to pass through and contact the metal walls, causing corrosion that you won’t be able to see until it’s too late.

Closed cell foam, which is more than twice the price of other top-performing insulation options, doesn’t allow moisture to pass through. However, it can trap moisture in three cases:

1. If it’s applied directly to a damp surface 
2. If it’s applied in a way that causes condensation to form
3. If it traps any water that leaks in from the outside

However, for buildings in drier climates, spray insulation can be a great option for adding insulation to existing buildings.

One important potential side effect of spray foam is oil canning. This is when the spray foam begins to shrink, a natural part of the cooling and curing processes. The shrinking can cause metal panels to pull inward if they’re too large, weak, or just unsupported. You can work to prevent oil canning by bracing your walls before insulating them.

How to Determine Insulation Needs

Getting the math right is the key to determining how much insulation you need, whether you’re insulating a metal shed, garage, workshop, or other building. Below, we’ll dig into where you need to have insulation.

Where to Insulate

It’s important to insulate the roof and walls of your metal building for the best protection against temperature variations and moisture buildup. Consider a cold front moving through your area: Chilly wind will whip your building’s sides and roof, and that cold air will cool the inside surface of the metal panels and cause condensation buildup if both the roof and walls aren’t properly insulated.

You can also insulate your building’s floor and foundation for complete protection. This isn’t as important as the walls and roof, however, because far less heat enters or escapes through the building’s floor than through its walls and roof.

• Tip: If your metal building has windows and doors, make sure they’re insulated and sealed to prevent any air leaks or gaps that can compromise your other insulation.

How to Calculate Insulation Costs

Because you’ll need insulation for your metal building’s walls and roof, it can be tricky to calculate the exact amount you’ll need. You’ll calculate the insulation needed for the roof and walls separately because each uses a different formula.

Here is how to calculate the cost to insulate a building up to 30’ wide (these formulas are for the metal buildings we sell, but you can also use them to approximate your costs for other metal buildings):

• Roof: (Width + 2’) x Frame Length x Price Per Square Foot
• Sides: Height x Frame Length x 2 sides x Price Per Square Foot
• Ends: (Height + 2’) x Width x 2 ends x Price Per Square Foot

Add two feet to the total width and height of your building to cover the gables on a sloped roof, which has a larger surface area than a flat roof would.

For example, if the frame of your building is 12′ x 20′, with sides that are 10′ tall, and you’re using double bubble insulation, your cost would be:

• Roof: (12 + 2) x 20 x $1.50 = $420
• Sides: 10 x 20 x 2 x $1.50 = $600
• Ends: (10 + 2) x 12 x 2 x $1.50 = $432
• Total: $1,452

The insulation prices for our 32′ to 60′ metal buildings use a complex pricing formula. To get the insulation cost for a metal building that is wider than 30’, contact us and we’d be happy to price the insulation on any size of metal garage you are looking for.

Metal Building Insulation FAQ

Here are a few of the most frequently asked questions about metal building insulation.

Can you insulate a metal building after it’s built?

Yes, you can insulate a metal building after it’s built. It’s easiest to insulate existing buildings using spray foam insulation, but this isn’t recommended for humid climates since spray foam can trap existing moisture and cause corrosion.

Does cheap insulation work well on metal buildings?

Cheap insulation may work for keeping moisture out of some metal buildings, but it won’t do as good a job as more high-quality insulation. You’re also not likely to find cheap insulation with any significant temperature protection.

Find a Metal Building That Suits Your Needs in Any Climate

Insulation is a key part of winterizing and protecting your investment, whether that’s your metal building or the goods inside of it. No matter if you’re looking to build a shed, workshop, barn, or garage, it’s a good idea to think about insulation during the planning process so you don’t have to worry about it later.

Get started by heading to our custom 3D builder below and visualizing what your new building will look like.