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Foam board insulation is easy to use and a great DIY way to add some insulation. It comes in standard-size 4×8 sheets and smaller sizes, in thicknesses from 1/4-in. to two inches. Some types of thicker foam board insulation are available, but may need to be special ordered.
In short, it's a great alternative to the common fiberglass batt insulation in most of our homes. It has a higher R-value per inch of thickness. It's also resistant to moisture and easy to work with.
There are a few kinds of foam board insulation DIYers should know about:
Because of its resistance to moisture, foam board insulation is a great choice whenever and wherever there's a chance it could get wet. Examples: an exterior foundation, inside a basement against the foundation, and on the outside of a house beneath a house wrap.
Foam board insulation is more expensive than traditional batt insulation, so use it only when moisture is a factor and it makes sense with your budget.
Foam board insulation is easy to cut with a circular saw and a masonry blade, or scored with a utility knife and snapped like you would drywall.
To attach the insulation, use screws with large washers or a special adhesive made for adhering foam board insulation. For smaller pieces, seal them in with caulk or spray foam.
We've curated below the most common questions asked about our top rigid insulation choices: THERMAX' Polyiso Insulation and STYROFOAM' XPS Insulation. With increased attention on resiliency and building code requirements of late, the most asked topics are about mildew, flame spread requirements, and how to material storage. Does it spark a question for you? Get in touch. Our building scientists want to help you succeed.
It's possible some of you just need product specs, and that's fine too. We've included those facts among the responses below.
Mold and mildew are nuisances every architect wants to avoid. We understand that completely. They can grow wherever sufficient moisture, spores, optimal temperatures and nutrients are present. The key factor is moisture, which can be controlled by adhering to sound construction practices. To make matters worse, condensation can be a source of moisture and a potential contributor to mildew growth. Condensation may occur when water vapor permeates through the wall, cools and condenses on the first cold surface it encounters.
One of the ways to manage moisture is to add insulation such that the condensing surface is not inside the wall system. Walls constructed with proper construction techniques and using an appropriate thickness of insulating sheathing will:
You will get efficient and thoughtful service from Decai.
STYROFOAM' Brand Extruded Polystyrene Foam Insulation products and Dow polyisocyanurate foam insulation products are not expected to provide a nutrient source for mold. They resist moisture absorption in the insulation itself. This further reduce the potential for mold and mildew growth.
To be clear, no building assembly is likely to be completely free from the potential for mold formation, but good building practices unrelated to insulated sheathing will further reduce the potential or mold formation. Ultimately, good construction detailing, compliance with proper installation guidelines for materials, and maintenance of the wall system are key to managing the moisture infiltration into the building envelope.
You'll be glad to know residential requirements for flame spread ratings are easy ' there are none. For commercial construction, however, the flame spread rating should be less than 500 according to CAN/ULC S102.2 (for thermal plastic materials) or CAN/ULC S102 (for thermoset materials).
Use our self-guided Canadian Code Assessment Engine to compare above grade wall strategies for building materials and design methods aligned to local code requirements. Try it today.
STYROFOAM' Extruded Foam Polystyrene Insulation products are manufactured to conform to ASTM C578 standards, which require specific minimum densities. We've listed some examples below:
Type X with minimum density of 1.30 pcf
Type IV with minimum density of1.55 pcf
Type VI with minimum density of 1.80 pcf
Type VII with minimum density of 2.20 pcf
Type V with minimum density of 3.00 pcf
As architects have likely heard, density is sometimes used to select a rigid foam insulation material for a particular application. It should be noted that there are other performance properties listed in ASTM C578 that are often more important to consider when choosing the proper product for an intended application.
Looking at Canada in particular, extruded polystyrene insulation products are covered by the standard ULC S701, which does NOT specify a density requirement.
If you are looking for more details, kindly visit Extruded Foam Insulation.