Metal buildings are increasingly popular thanks to quick installation, low upfront costs, and high durability.
In some sectors, metal buildings now make up the majority of new builds. However, if you are installing a metal building, you have to consider insulation.
In most cases, insulating your building will offer benefits including reduced energy usage, decreased humidity and condensation, and a better ability to keep goods inside safe no matter the weather.
At the same time, the costs of insulating a metal building can vary significantly depending on the material chosen. However, most insulation types have pros and cons and some are better suited to different applications than others.
The table below gives a quick comparison of the top insulation options for metal buildings.
| Material | Cost Per Sq Ft* | R-Value |
|---|---|---|
| Rigid Board | $1.80-$3.20 | 4.5-6.8 |
| Fiberglass Batting | $0.30-$1.50 | 2.2-3.8 |
| Rock Wool Batting | $1.10-$3.10 | 3.2-4.5 |
| Spray Foam | $1.00-$4.50 | 4.6-7 |
| Loose Fill | $0.25-$2.00 | 2.1-3.8 |
| Insulated Metal Panels | $7-$14 | 5-7.2 |
| Filled Cavity | $1-$3 | 3.5-4.8 |
| Fabric Liner | $1-$3.50 | 3.5-7 |
*Please note: these costs are estimates and were correct as of December 2022.
1. Rigid Board
Rigid board or rigid foam board insulation is the most popular insulation option for metal buildings.
Here, rigid board is most commonly sold in polystyrene foam, which offers advantages including being lightweight, cheap, and readily available.
However, you can also choose other materials. Options include Polyiso (PIR), Polystyrene (XPS) and Expanded Polystyrene (EPS).
In each case, the foam boards are normally backed with a reflective material, such as an aluminum coating. Then, you can install them by simply pressing them between the studs and pylons of the building.
Often, they work for both walls and ceilings. Most are available in thicknesses of 3/8ths to 2.5”.
Rigid board is popular, affordable, and can offer very good R-values. It’s also easy to install, which is one of the major perks of the insulation option.
- $1.80-$3.20 per square foot
- R-values range between 4.5 and 6.8 on average
- Thicknesses of up to 2.5”
- Very good value for money
- Ease of Installation 4/5
- Suitable for walls and ceiling
- The standard option for metal buildings
2. Fiberglass Batting
Fiberglass batting, blankets, and rolls are another extremely common insulation option. However, while they were once the most popular insulation used in any build, their popularity is waning thanks to the introduction of high-density foams.
Today, fiberglass batting offers a mid-level insulation with a relatively low cost.
If you only need light insulation, for example if your environment is relatively temperate or it’s not important to maintain a consistent temperature, fiberglass batting offers a great mix of insulation and low installation costs.
Here, fiberglass fibers are pressed into a sheet against a paper or reflective surface. Then, that batting or blanket is pressed into place between studs and glued or tacked into place. This means that even amateurs can often easily install fiberglass.
However, it requires safety equipment including respirators and eyewear to install safely.
- $0.30-$1.50 per square foot
- R-values of up to 3.8 per square inch
- Thickness of up to 6.25”
- Cheap and efficient insulation
- Is thicker than foam board so takes up more space
- Ease of Installation: 4/5
- Suitable for walls and ceilings
- The best low-cost insulation you can install yourself
3. Rock Wool Batting
Rock wool batting is a higher-density batting than fiberglass, meaning that it offers more insulation. In addition, mineral batting provides better fire resistance and better moisture resistance than most fiberglass.
That can make it a good alternative to fiberglass for building owners looking to improve fire resistance and who want more insulation.
However, with higher upfront costs and only slightly increased insulative properties, mineral batting can be a poor choice for many metal buildings.
Stone wool insulations can also offer benefits like being more resistant to rot, mold, and fungus. This makes them superior to foam in very damp or humid environments.
In addition, you can choose semi-rigid rock wool, which can be easier to install.
- $1.10-$3.10 per square foot
- 3.2-4.5 average R-Value
- Thickness of up to 6.25”
- Cheap and efficient insulation
- Highly mold and fungus resistant
- Ease of installation: 4/5
- Suitable for walls and ceilings
- The best insulation for damp environments
4. Spray Foam
Spray foam insulation is a high-density foam that is sprayed into place using a professional machine and tank.
This insulation can be applied at nearly any thickness, across the full outer wall and ceiling of your metal building. That makes it extremely efficient at filling every cavity and gap.
However, spray foam insulation requires professional insulation. This means it is normally more expensive than batting or rigid board.
In addition, any new customizations to the building, such as installing windows or doors, will require re-spraying or re-filling the area.
- $1.00-$4.50 per square foot
- R-values of up to 7
- Requires professional insulation
- One of the best insulating options on the market
- Suitable for walls and ceilings
- Installs within a day for most buildings
5. Loose Fill
Loose fill insulation is made up of either fiberglass, paper, or Styrofoam pellets. Depending on the type, it can offer R-values of up to 3.8.
However, it also requires building a cavity to blow insulation into. That can mean installing the interior walls first and then adding insulation.
For this reason, loose-fill insulation is a less-common choice for insulating metal buildings.
However, the low cost combined with potentially high R-values means that it’s popular in buildings that are set to have interior walls.
In some cases, homeowners also use a combination of foam board against the outer wall and loose fill to fill the remaining cavities after building interior walls.
That can offer a good value and high insulation. However, loose fill requires good isolation and good sealing for the rest of the building.
- $0.25-$2.00 per square foot
- R-values of up to 3.8
- Requires professional installation
- One of the cheapest insulation options on the market
- Suitable for walls and ceilings
- Requires secondary wall for installation
- Installs within a day for most buildings
5. Insulated Metal Panels
Insulated metal panels are an increasingly popular insulation option for metal buildings.
Here, you replace the standard steel metal panels on the outside of the building with thicker panels that have insulation built-in. This can be expensive, with most costing over $7 per square foot.
However, it also means reducing the impact of insulation on the inside of the building.
That can mean creating a highly insulated building without any interior walls. That’s ideal for warehouses, buildings that need very good insulation, and anywhere where space is a concern.
However, insulated metal panels are still a specialty product. Not all metal building manufacturers will offer them. And, because they’re part of the building, you’ll have to source them from your metal building installer.
- $7-$14 per square foot
- R-values of up to 7.2
- Requires professional installation
- Expensive, but includes the cost of wall paneling
- Suitable for walls and ceilings
- Enables secondary installations of insulation on the inside of the panels
- Installs as part of the original building
6. Filled Cavity
Filled cavity insulation involves creating a false cavity by building a secondary wall in the building. You then blow or spray new insulation into the cavity, creating a dense infill to provide the R-values desired.
This insulation is cheap, fast to install, and often works very well for metal buildings that are already getting drywall. However, it’s not a good choice for warehouses and other buildings that won’t have drywall.
Filled cavity insulation can also offer R-values of up to 4.8. That means it’s one of the highest R-value options for the money on the market.
If you’re not already installing a secondary cavity, though, the cost of the building materials to do so will offset those costs.
- $1-$3 per square foot
- R-values of 3.5-4.8
- Requires professional installation
- Requires a cavity inside the wall
- Suitable for walls and ceilings
- Fills spaces between interior and exterior walls
- Normally installs in less than a day
7. Fabric Liner
Fabric liner insulations use a fabric liner to hold loose fill insulation in place, allowing you to install insulation before putting walls in.
Here, the fabric is hung from the girders and pylons and then attached to the wall studs. In most cases, fabric liners are also fire-resistant and provide a vapor barrier. In addition, you don’t normally have to install a wall over them.
This can make fabric liners a good, low-cost solution for insulating warehousing and other buildings that don’t need a high interior finish or drywall. In addition, with costs averaging at $2.25 per square foot, fabric liner systems are relatively cheap.
- $1-$3.50 per square foot
- R-values of 3.5-7
- Requires professional installation
- Installation can take several days or several weeks depending on building size
- Suitable for walls and ceilings
- Does not require interior walls
Cheapest Ways To Insulate A Metal Building
In most cases, there are three main factors impacting the cost of insulating a metal building.
These include the cost of materials, labor, and long-term efficacy. For example:
- Material Costs – Fiberglass batting is the cheapest insulation option you can choose. However, it does require covering to protect the insulation and people working in the building. This means that while fiberglass batting starts at about $0.30 per square foot, you might pay more in total for the interior walls.
- Labor Costs – Installing fiberglass batting is often the cheapest option to do yourself. However, if you’re paying a professional, costs can add up quickly. Most construction labor costs from $10-$15 per hour and goes up to over $100 in union areas. The more labor costs, the more likely you’re better off looking into a spray in solution.
- Efficacy – Your insulation has to provide the insulation values you need and the moisture resistance you need. Otherwise, you’ll quickly find yourself replacing or reinforcing it.
Fiberglass blankets or batting are the cheapest options you can choose, especially if you do the installation yourself.
However, the rigid board is normally the go-to option because it’s faster to install.
Benefits Of Insulating Steel Buildings
There are multiple reasons you might choose to insulate your metal building.
Reducing Energy Usage
If you have to heat and cool your metal building, insulation is a must. That’s true even if you only have to maintain a stable temperature for people to work in.
For example, warehouses can get away with relatively light insulation, because you mostly need to stabilize the temperature.
On the other hand, office buildings and manufacturing areas have to provide a consistent stable temperature to work in, so good insulation can save you considerably on long-term heating and cooling costs.
Meeting Building Codes
Many building codes mandate a specific amount of insulation for any heated or cooled area.
In addition, you may be required to use a certain amount of insulation in your area to ensure appropriate moisture control and sound control. In this case, you’ll have to check local building codes to see what your obligations are.
Sound Damping
Insulation can reduce noise going in and out of your building. This can be important for manufacturing, shops, commercial areas, and homes.
If your expected activities will create noise, using insulation can prevent complaints from neighbors. In addition, if your building is in a noisy area, using insulation can enable sound reduction in the building.
Reducing Moisture
Good insulation reduces thermal bridging and therefore moisture buildup on the inside of the building. In fact, for warehousing, that’s the primary reason to use insulation.
Here, thick foam board or fiberglass batting performs very well at reducing the amount of moisture that moves inside. However, if you live in a very damp environment, you may want a denser and more moisture-resistant solution, such as rock wool.
Metal Building Roof Insulation Options
Most insulation that works in your metal building walls is also suitable for the roof.
For example:
- Fiberglass Blankets – Fiberglass blankets and batting can be installed on your ceiling just like on your walls. Here, you press the fiberglass between the pylons. Then, you glue or tack it into place. You can further secure it with a line or blanket system. You may need more than one layer of batting to meet most energy codes.
- Rigid Board – Rigid board installation easily fits into most metal building ceilings. However, you will have to double up thin layers to ensure continuous layers and overlap over purlins and seams. Many rigid board installers sell ceiling clip attachments for this purpose.
- Multi-layer Systems – Multi-layer insulation systems normally include fabric liners with fiberglass or loose-fill insulation. This provides a good value for money and meets almost all energy codes. However, installation can be complex and time-consuming, so you’ll need a professional installer.
- Spray Foam – Spray foam insulation coats ceilings as easily as walls. However, in most cases, you’ll have to cover it rather than leaving it exposed.
- Insulated Metal Panels – Choosing insulated metal panels for roofing material can free you from most of the need to separately insulate your roof.