Metal Building Insulation – Did you know that every steel building other than carports require an insulation package? If you’re a first time buyer, this fact may not have crossed your mind, but metal building insulation is essential if you want your structure to last for generations.
Metal Building Insulation Options
Metal and steel buildings may be durable, but this choice of construction materials also presents a challenge when looking for insulation to use on such buildings.
Choosing the right insulation for a metal building kit helps to reduce energy consumption and, in some states, allow those constructing the building to claim tax incentives for making the effort to save energy.
Steel and metal panels alone offer no protection from the outside temperature, meaning there is no natural barrier to heat and cold. Adding the right type of insulation helps to control the conduction of outside temperatures. The result will be a building that stays cooler in warmer months and warmer once the temperature drops. There are four basic types of insulation, all of which can have their place in a metal or steel buildings.
This type of insulation consists of loose fibers or fiber pellets. These fibers are blown into building cavities with special equipment. Loose-fill insulation can be more expensive, but does fill corners better and reduces air leakage.
Additionally, this type of insulation provides a better sound barrier. Cellulose fiber is made from recycled newspapers that have been chemically treated to be flame retardant and resistant to moisture.
This is a good option when looking to take advantage of green construction perks. Loose fill insulation is generally used in walls, attics and floors where it is applied through a moist-spray technique or a dry-pack process.
Rock wool or fiberglass provides fuller coverage that is better for steel or metal buildings where it is applied using a Blow-in-Blanket system that blows the insulation into open stud cavities. Loose-fill insulation has a R-3 to R-4 value per inch. Cellulose fiber increases the insulating value by 30 percent over rock wool or other materials.
Batt and Blanket Insulation
Mineral fiber consisting of rock wool or processed fiberglass is typically used for this type of insulation. Batt insulation is usually the most inexpensive of the insulation available for use in walls.
However, it has to be installed carefully to be effective. Batt insulation is generally used in floors, ceilings and walls. Batt insulation works best for stud spacing of 16-24 inches or a standard joist. Some forms of batt insulation include a radiant barrier backing.
This is especially effective in steel or metal buildings due to the lack of natural insulation. Blanket insulation comes in rolls cut to specification and batt insulation typically comes in lengths in 4-8 ft. lengths. Both forms of insulation have an R-value of R-3 per inch.
Rigid Board Insulation
This type of insulation is usually made from polyurethane, fiberglass or polystyrene. It can be cut to the desired thickness, increasing the insulating value from R-4 to R-8 per inch.
Rigid board insulation is best for reproofing on flat roofs. It is also good for use on basement walls or as perimeter insulation in cathedral ceilings. It can also be used on concrete slab edges.
This insulation needs to be covered with 1/2-inch gypsum board or other flame-retardant materials when applied to interior spaces. Weather-proof facing is required for exterior applications. Local municipalities may require additional covering.
Spray Foam Insulation
This type of insulation is liquid and contains a foaming agent and a polymer such as polyurethane. The liquid mixture is sprayed into walls, floors and ceilings.
Spray foam insulation expands as it is applied and turns into a solid cellular plastic consisting of air-filled cells. This type of insulation is good for steel and metal buildings because it fills every space, no matter how small. This type of insulation is ideal for usually shaped designs or getting around obstructions.
Spray foam insulation is more expensive than batt insulation, but provides a better air barrier. This is a major plus for metal and steel buildings. Additionally, spray foam insulation does not require caulking and other additional barriers since it is already airtight.
Protection from Condensation
Condensation is a major concern in metal and steel buildings. Insulation serves to protect a metal building from condensation, which can cause damage over time. Insulation creates a vapor barrier to reduce how much condensation takes place directly on the steel panels.
Another issues with a steel or metal building is humidity. A concrete foundation that is not fully cured can be a contributing factor to increased humidity and condensation. Steel or metal buildings located in colder climates can experience condensation from exposure to ice and frost.
A regular pattern of freezing and thawing can cause frost to melt, drip water and produce condensation. Insulation placed around the red iron before metal sheeting is installed creates a “thermal break” between outside sheeting and internal framing to prevent condensation.
Protection from Mold
Insulation that is not properly installed may trap mold within the walls of a steel building. Improper maintenance is another common cause of mold in steel buildings.
Animals and birds may damage insulation in metal buildings as they try to create a home. It is not always possible to prevent every possible cause of mold. The best defense is to be aware of what is going on inside the walls of a building.
This is accomplished with regular inspections using special equipment to detect possible insulation issues. Once an issue is inspected, the area in question needs to be opened to correct the issue. This may include replacing insulation that is damaged.
Fiberglass and Insulation Materials
Fiberglass is usually the material of choice for insulation used in steel and metal buildings. Black or white vinyl fencing laminated on one side is usually a feature of the insulation to prevent moisture.
White facing is sometimes used to counter the impact of ambient light by reflecting it away from the surface of the building. Any of the four basic types of insulation may be used in metal and steel buildings.
The choice of materials used depends on several factors, such as where the building is located and how the overall structure is designed. Most metal buildings use different types of insulation for different parts of a building. If properly installed and maintained, a steel or metal building can be highly durable, energy-efficient and well-insulated for many years.
Metal Building Insulation Design Ideas
Insulation for Metal Buildings
Insulation serves a number of important purposes in steel buildings. Besides providing resistance to heat transfer, it also minimizes the buildup of condensation in a building, and reduces the level of outside noise that can be heard within. If you plan on heating and cooling a building, a little extra expenditure on insulation will yield major savings in long-run energy costs.
Traditional fiberglass blankets insulation is not the most efficient choice in a steel building. For the best insulation in this application choose a combination of fiberglass and reflective insulations (such as eFoil or Solar Guard).
Pay attention to the facing of your insulation (the side that faces into the building), and make sure to choose something durable. Products with a layer of scrim (nylon or fiberglass mesh) are the best choice.
If they also have a light or reflective color, they will help to maintain brightness inside the building.The power of insulation to prevent heat transfer is measured relatively, in “R-values.” The more effective a layer of insulation is, the higher its R-value rating. The table at right shows the respective R-values for several thicknesses of fiberglass blanket, a common insulation material that many people are familiar with.
Liner panels can be installed over the insulation (check with the manufacturer for details) and traditional walls can also be framed on top of the insulation where necessary.
Make sure you consider insulation with good permeability. Find one with a low perm-rating (less than 0.1) and you will reduce the transfer of condensation.
Today, there are a variety of building insulation material options available, and new technologies as well as long-forgotten ideas are coming to public attention as thermal resistance and energy savings become more of a concern in green building design. Below, from the Insulation Fact Sheet (DOE 2002,) are the r-values for some common building insulation materials expressed in r-value per inch of material.
* Fiberglass batts 2.9-3.8
* High performance fiberglass batts 3.7-4.3
* Cotton batts 3.0-3.7
* Sprayed polyurethane foam 5.6-6.2
* Loose-fill rockwool 2.7-3.0
Good Metal Building Insulation will have the following benefits/features:
1. High R value (thermal break)
2. Eliminate condensation
3. Radiant heat barrier
4. Not be affected by humidity
5. Vapor barrier
6. Install easily
7. Not allow nesting for rodents, birds or bugs
8. Recognized by ICCES and Qualified by Energy Star
Steel buildings and metal buildings are uniquely affected by:
2. Radiant Heat
Steel building insulation options are limited to insulations that address at least these three factors.
Fiberglass blanket is not the only type of insulation on the market, nor does it provide the best insulation when used by itself. 80% of heat transferred by radiation (like solar heat) goes through fiberglass. Reflective insulations, such as eFoil, and the fireproof Solar Guard, boast the capacity to prevent all three modes of heat transfer (conduction, convection, and radiation). It also bears mentioning that fiberglass packed too tightly (like 6” crammed into the frame of steel building) has a tendency to under-perform. If a rating of R-19 or greater is required, it is better to install a combination of fiberglass blanket and reflective insulation.
The part of the insulation that faces the inside of the building is known as the facing. Facing material must be carefully selected if it is going to be left exposed. In this case, the facing doubles as the inner wall material, and needs to be a type which is reinforced with a layer of scrim (fiberglass or nylon mesh). This will increase its durability, protecting it from punctures and scratches. Because of its more vulnerable location, the durability of wall facing is more important than that of the roof facing. “Bird proof” varieties are available for agricultural buildings. It is also worth noting that the colour of exposed facing will contribute to the light inside of a building. With white or reflective foil facing, fewer sources are required to light up the interior. Black facing may be preferred for a darker ambience.
Liner panels (partial, and full-height) are available from some manufacturers, which protect the insulation, and contribute to the inner appearance of their buildings. General contractors can also be hired to add walls. When the insulation is covered and protected, the durability of the facing can be reduced.
Permeability – To minimize the transfer of condensation into a steel building, insulation facing with a low perm-rating must be chosen. With a perm-rating of 1.0, plain vinyl is not considered protection against condensation. Facing with a perm-rating less than one tenth (0.1) will provide sufficient protection against condensation for most applications.
Workability – Certain types of insulation cannot be shipped or installed in cold weather during winter. It is a good idea to ask the manufacturer about the material’s workability if a project is taking place in a cold climate.