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Q: What is the R-value of Insulfoam EPS insulation?
Insulfoam EPS has R-values that vary depending on temperature and the density of the product installed. For instance, our standard Type I, 1# R-TECH, sold in home improvement stores, has an average R-value of about 3.9 per inch at 75°F.
Q: Can EPS go directly under drywall?
Yes. Drywall is a common finish material that can be applied directly over Insulfoam EPS and R-TECH.
Q: What types of adhesives and tapes work with EPS insulation?
Acrylics, urethanes, and polyether adhesives work best. Tapes used in weather resistant barrier applications are typically compatible with Insulfoam EPS and R-TECH. Refer to our technical bulletin for more information.
Q: What types of paints are compatible with EPS insulation?
Quality latex paints and primers should be used for best results. Avoid products that contain solvents such as xylene, acetone, etc.
Q: What’s the best way to cut EPS?
You can use an insulation knife, razor knife, or any other specialty foam knife or foam saw blade.
Q: How can EPS be fastened to a wall?
You can use cap screws, cap nails, adhesives, or minimum 1″-wide staples to fasten insulation to the wall.
Q: Will EPS harm my pets if used inside my house?
No, this material is non-toxic to animals inside the home.
Q: Can EPS be left exposed?
It depends on the application; it can be left exposed in an attic or crawlspace type of application. Local building codes should be reviewed for exposed interior applications. If it’s an exterior application, it should be covered with some sort of finishing material.
Q: What differentiates one rigid foam insulation from another?
Building design and construction professionals can select from several rigid foam insulations, all of which perform well in helping buildings retain or keep out heat. Yet, there are important factors to consider when evaluating some of the primary rigid roam products, like expanded polystyrene (EPS), extruded polystyrene (XPS) and polyisocyanurate (polyiso).
- Insulating performance per unit of measure
- Long-term thermal resistance (LTTR)
- Moisture absorption rates
- Product make-up and applications
- Cost-saving insulation approaches
Q: Should I use faced or unfaced wall insulation?
A: “Facing” is a layer attached to the insulation material that can act as a vapor retarder when properly installed with sealed joints to prevent moisture from seeping across the walls and throughout the building envelope. Typically, faced insulation is ideal for moisture-prone applications such as walls and basements. If you work in a wet and humid climate, local building codes may mandate faced insulation in areas where no insulation is present.
Wall insulation being “unfaced” doesn’t necessarily means it’s a poor choice; it only means ensuring it’s the right product for your project. Unfaced insulation lacks a vapor retarder, meaning it’s designed to allow a wall to breathe and provide additional insulation. Many wall applications—inside or out—add unfaced EPS insulation. To underscore this practice, building science is leaning towards allowing a wall to breathe (depending on its environment and design).
Q: Can wall insulation go directly under dry wall?
Drywall is a common finish material that can be applied directly over EPS wall insulation products.
Q: What R-value do I need for wall insulation?
In general, the higher an insulation material’s R-value, the better the product is at resisting the flow of heat. That said, your region will largely dictate what your project’s insulation value should be. Look at the Department of Energy’s website to determine the appropriate R-value for your project.
Q: How can EPS be fastened to a wall?
The ease with which EPS products can be installed across a building envelope makes it possible for residential building professionals and do-it-yourselfers to dramatically upgrade a home’s insulating power. EPS products, such as our R-TECH Insulation Panels, can be cut with common household tools such as a razor knife or reciprocating saw. Pre-cut panels of EPS wall insulation can be installed using screws, cap nails, adhesives, or 1-inch staples. For additional information on the straightforward install process, watch our online installation tutorials.
Q: Can EPS be used in a basement or attic?
Yes, it’s a great interior insulation solution for both the basement and attic. Check out Insulfoam YouTube channel for videos on installing Basement applications directly against foundation walls, between furring strips, etc.
Q: Which way does the metallic side face on Insulfoam R-TECH?
The metallic facer on Insulfoam R-TECH may provide additional R-Value if it’s facing a dead air space. If there is no dead air space, it doesn’t matter which way the metallic side is facing. Placing the metallic facer on Insulfoam R-Tech may provide additional R-Value if it's facing a dead air space.
Q: Can R-TECH be an air barrier or Weather Resistant Barrier (WRB)?
R-TECH by nature is an air barrier, and with the seams taped, it becomes a vapor retarder. It is also a moisture barrier, as it is hydrophobic, and is a weather resistant barrier when joints are taped with appropriate products.
Q: Is R-TECH rated for blocking sound?
No, it does little for sound deadening.
Q: What compressive strength do you need for Geofoam?
Many projects design & build for higher load bearing densities then are required, thus costing significantly more time and money than is necessary. ASTM’s D6817 is the specification for rigid cellular polystyrene geofoam. Designing to this standard not only helps engineers meet technical specifications but also helps save money and time by using EPS (expanded polystyrene) geofoam, which is listed by the standard, as a structural void fill. Geofoam has the compressive strength to bear heavy loads like concrete slabs, soil overburden, highway trucks and even airplane traffic and has gained widespread acceptance in load-bearing applications with federal and state entities like DoTs, airports and commercial projects.