What is Rigid Foam insulation ? Pros and Cons
What is Rigid Foam ?
Rigid foam insulation, also called foam board or board-stock, is made from foam plastics
(Commonly made of polystyrene, polyisocyanurate, or polyurethane, ) that are mixed with other
chemicals to create rigid foam sheets or boards and is a popular choice for insulating foundations and building exteriors.
Types of Foam Board Insulation
Expanded Polystyrene (EPS)
Extruded Polystyrene (XPS)
Graphite Polystyrene (GPS)
Polyisocyanurate (Polyiso, or ISO).
Rigid foam insulation uses one of three materials:
high-quality, green-friendly polyisocyanurate;
Where Can Rigid Foam Board Insulation Be Used?
Foam insulation board is applicable virtually anywhere that insulation is used in the home.
You can use it on foundations, in basements, in regular walls , roofs, Indoors ,Radiant Heat Floors ,Rim Joists and attics.
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.
They offer higher R-Values than other insulating materials of the same thickness, and they’re easy to work with. Ratings range from R-4 to R-6.5 per inch.
Rigid foam can provide soundproofing to interior walls or to sequester interior spaces that are not climate controlled.
Rigid foam board insulation is offered in a variety of thicknesses, lengths, and facings so it can be customized to fit properly for your project.
Rigid foam performs well when subjected to moisture and it does not change dimensions, split, or crack.
Better choice for DIY projects than spray foam because it there is less chance for error.
EPS can be bought with foil and plastic facings so that it is water resistant and can be used underground.
This will help limit the amount of moisture buildup that can happen in your home, reducing the chances of mold growth.
Foam boards are easily cut and can be installed in any temperature.
The only style of insulation that blocks thermal conduction through structural elements.
No harmful emissions are created during installation.
The expanded polystyrene board is the cheapest foam board on the market…and Mid-priced, between expensive spray foams and low-cost blown and batt styles.
Best choice for insulating crawl spaces and basement walls.
You can’t use rigid foam or foam board to insulate existing walls until you knock the wall down, install the board, and then re-drywall and paint.
More time-consuming to install than spray foam in most applications.
Joints between sheets and boards must be taped to prevent air flow.
Expanded polystyrene boards have air bubbles that can stop heat transfer but can collect moisture making it ineffective for preventing mold and mildew growth.
Polyiso suffers from decreasing R-values over time.
Rigid foam is susceptible to sunlight.
Rigid foam boards are slightly more expensive than traditional insulation materials used.
Flame retardants in foam insulation are an important line of defense when it comes to fire safety.
see also :
What is Fiberglass Insulation , Pros and Cons ?