Your Guide to Metal Building Insulation

(8-min read)

Save money and energy by selecting the right insulation for your metal building project.

When most people think of metal buildings, they imagine a steel barn, an automotive garage, or a workshop. As they mentally step inside, the interior walls look just like the exterior metal panels with virtually no insulation. For this reason, many don’t associate metal buildings with homes, offices, churches, or anything other than merely utilitarian structures. Thanks to advances in insulation technology, steel buildings can be used for any purpose imaginable. The key to making the interior of metal buildings fully livable is selecting the right kind of insulation.

Why Insulation is Crucial in Steel Buildings

Placing your hand on the inside of an uninsulated metal building on a summer’s day versus that of an uninsulated wood building, such as a shed, you will notice a considerable difference. Metal is an extremely efficient conductor of heat, making the need to insulate metal buildings for climate-controlled situations essential.

Preventing Internal Condensation Buildup

Without proper insulation and ventilation, metal construction does not breathe. For this reason, proper insulation in steel buildings is necessary. Insulation also works to prevent an excessive buildup of condensation within a metal building. If excessive moisture accumulates within a metal structure, this can result in damage from rust and corrosion.

Metal Buildings: Still Superior Construction

At this point, it may sound like metal is a poor construction material. On the contrary, despite its need for proper insulation, it remains one of the most durable building materials on the market. Let’s take a look at how metal buildings can be outfitted with the appropriate insulation and what kinds of insulation materials are available.

Where Insulation is Installed in Metal Buildings and Homes

Similar to wooden construction, the insulation in steel buildings or metal homes is installed between the studs and the internal components of the structure. Depending on the structure and the style of insulation used, insulation is laid or sprayed between walls studs, sheetrock, or internal plaster to help regulate the temperature of interior spaces as well as to reduce noise.

Insulations Rating Systems

When insulating different aspects of a metal home or other structure, there are a few different rating systems used to determine the level of insulation provided by each material.

R-value Rating

The R-value is a rating system that informs construction professionals and building owners the level of insulation existent in the material. An R-rating typically only rates one single material and not a system of various materials.

U-value Rating

Unlike an R-value, a U-value rating tells building owners and construction professionals the insulation strength of a system — various materials working together, such as a window, door, or other combination of parts in a mechanism.

Condensation Prevention with Vapor Barriers

A concern with any constructed structure is how well it prevents moisture from permeating the walls and ceilings. A vapor retarder, also known as a vapor barrier, is used to protect the structure from moisture. These vapor retarders or barriers are usually sheets of plastic or possibly foil placed within the walls and other areas prone to the accumulation of condensation.

Style of Insulation for Metal Buildings


Batt & Blanket Insulation

Batt and blanket insulation materials are composed of rock wool, fibrous minerals, or fiberglass that has been processed into a wool-like state. This style of insulation is not only more expensive than most other types, but also requires a much more careful installation process. This more specialized installation and higher quality material makes for higher R-values. 
R-value: between R-2.9 to R-3.8 per inch of thickness.


Loose-Fill Insulation

Rather than laying down in sheets, loose-fill insulation is installed by being blown in between walls and into crevices with specialized equipment. The insulation itself comes in the form of fibrous pellets or shredded fibrous material. One advantage this insulation and its installation method have over batt and blanket is the ability to insulate hard-to-reach areas. 

R-value: between R-2.2 to R-2.7 per inch thickness. 


Spray Foam Insulation

Starting off as a liquid, this foam insulation material is sprayed between walls and the other regions in need of insulation. The material then sets up and hardens into form-fitting insulation. The moisture is replaced with captured air. Like loose-fill, spray foam insulation is especially useful for inaccessible areas but is much more resistant to wear due to its rigid form.

R-value: between R-3.7 and R-6.5 per inch thickness.


Fiberglass Insulation

It’s not uncommon to see fiberglass insulation used on construction sites or even in do-it-yourself projects due to its price, ease of installation, and its ability to insulate metal homes and buildings adequately. No special equipment is required for its installation, though those handling it are urged to don protective masks, eyewear, gloves, and garments due to shedding fiberglass fibers. Even though it is a very efficient form of insulation, its tendency to absorb moisture and attract pests for nesting makes proper vapor barriers a must when using fiberglass insulation.

R-value: between R-11 and R-28 per inch thickness depending on the variety. 


Rigid Board Insulation

Rigid board insulation is among the simplest forms of insulation to handle and install. This form of insulation comes in large rigid sheets composed of polystyrene (styrofoam), fiberglass, or polyurethane. It can be easily trimmed to fit wherever needed without any special tools. Not only is rigid board insulation an excellent insulator of heat, but it can also act as a sound barrier against condensation and excess noise.

R-value: about R-5.


Reflective Foil

Typically used in concert with looser batting-like forms of insulation, reflective foil insulation acts as a heat barrier within the walls of a metal home. Reflective foil is known not only for its ability to keep heat from penetrating its thin metal construction, but also as a moisture barrier. Though immensely useful, reflective foil insulation isn’t the most affordable addition. Still, the added energy efficiencies can make up the cost over time.

R-value: By itself, but R-1, but it is usually used with other forms of insulation.


Insulated Metal Panels

Wouldn’t it be nice if the insulation were baked right into the panels themselves? Well, with insulated panels, this is the case. Insulated panels are manufactured metal panels that contain a foam core of insulation. Think of it as a foam insulation sandwich with two sections of steel as the bread. While they tend to be more costly than standard metal panels, they can significantly reduce assembly and construction times of a steel building or metal home.


Steel Building Insulation: a Lot to Consider

There is a lot to consider when deciding which kind of insulation to use when constructing your steel building or metal home. Though some types are much cheaper to install, it is crucial to weigh long-term energy efficiency against the initial cost of construction. Though a highly efficient form of insulation may cost quite a bit now, it may pay for itself in the long run with savings in utility costs.

Need Help Deciding? Lucas Metal Works Has Your Back

If you have more questions about building a metal commercial building or the metal home of your dreams, the Oklahoma-based metal home experts from Lucas Metal Works can help.

Request Your Free Quote on Metal Building Construction Now