Home Improvement

Can rigid insulation be exposed?

Rigid foam insulation, whether it is expanded or extruded polystyrene, does have to be covered if it is installed in the interior of a building. This wall covering must have a minimum fire rating to protect the insulation from quick combustion during a fire.Jan 8, 2011

Can rigid foam board be left exposed?

Tests have shown that these laminated boards can withstand UV ray damage for a reasonably long time. That said, it’s still advisable to cover any foam board insulation exposed to the Sun within 30-60 days at the most. On most projects, that’s more than enough time to finish the exterior walls.

Can rigid foam insulation get wet?

When to use foam board insulation? Because of its resistance to moisture, foam board insulation is a great choice whenever and wherever there is a chance it could get wet, such as: an exterior foundation, inside a basement against the foundation, and on the outside of a house beneath a house wrap.

What foam board can be left exposed?

Dow Styrofoam and Owens Corning Foamular are two products that pass the burn test and can be left unprotected in an isolated crawlspace. Building codes restrict the use of unprotected foam in habitable or accessible spaces.

Can you cover foam board insulation?

Insulation Protection

There is no perfect material for covering and protecting exterior foam on foundations. Use metal or plastic reinforcing to strengthen the cement parging on foundation foam boards. The most common approach is to apply a stucco-like “parged” finish with a surface-bonding cement.

What happens if foam board insulation gets wet?

Wet insulation is prone to pests, mold, mildew, and eventually, it can cause damage to your house. It can change the air quality of the home, efficiency of the insulation, and the structure, which can lead to more costs.

What is the difference between pink and blue foam board?

Main Difference Between Pink And Blue Foam Boards

The two products also have the same insulating power. However, blue foam boards are manufactured by Dow Chemical Co. whereas the pink foam boards are manufactured by Owens Corning company. The boards are marketed under different brand names.

Does rigid foam insulation need vapor barrier?

Foam insulation usually does not require a vapor barrier. For some foam insulation types, such as closed-cell spray foam and foam board insulation, the insulation itself stops the movement of most water vapor.

Which rigid foam insulation is best?


Choose the right type of rigid foam for your needs
Polyisocyanurate: Known as polyiso for short, polyisocyanurate foam has the highest R-value per inch (R-6.5 to R-6.8) of any rigid insulation. This type of rigid foam usually comes with a reflective foil facing on both sides, so it can also serve as a radiant barrier.

Which is better EPS or XPS?

In general, when comparing EPS and XPS board densities, the compressive strength of XPS is greater than that of EPS. For EPS to achieve the same compressive strength as XPS, the density of the foam would need to be increased, often resulting in a greater thickness of board being required.

Is XPS a vapor barrier?

XPS is manufactured in both an unfaced form or with different plastic facings. However, XPS is considered a vapor retarder, not a vapor barrier.

How good is XPS insulation?

Just like with EPS, energy efficiency is the primary feature of XPS insulation. Due to its physical properties, XPS has a higher r-value than EPS at 4.7 per inch. In the past, XPS manufacturers were able to claim r-values closer to 5.0 per inch.