Find the right insulation for your home

When it comes to insulation there are many types to choose from, each with their own pros and cons. In the case of Foam board insulation, there are three types that are commonly used in the construction of homes on Long Island, and it is important to know which will provide you with the best results. When it comes to the energy efficiency of your home, your choice of insulation is an important one.

  • Expanded Polystyrene (EPS) foam board, made of Styrofoam beads, is the lesser of 
    thethree. This type of foam board has gaps between the beads that allow air and water to migrate.
  • Extruded Polystyrene (XPS) foam board is made from the same compound as EPS but the manufacturing process creates a continuous closed cell matrix that has excellent water and air resistance.
  • Polyisocyanurate or Polyiso foam board is the best type of the three, offering the best water resistance to impede the passage of water. With a foil layer on each side, it offers the best fire rating of the three as well.

All prevent air from leaking through in most conditions and all will provide a reasonable thermal barrier when applied in thicknesses of 1.5" to 2" thickness. But, only XPS and Polyiso will stop water from passing through and reduce the chance of mold. Additionally, all need to be sealed along its edges to provide optimal effectiveness. Green Audit USA exclusively uses Polyiso and XPS to provide the highest levels of water and air resistance.

Typically, foam board insulation is used for roof insulation, under attic platform as well as in basement and crawlspace insulation. This is due to its ability to prevent the passage of water and air, offering a high level of energy efficiency.

To learn more about foam board, any of our other services, or schedule a free home energy audit, contact us today!


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Steve, Steve

I got the LIPA rebate today, at the promised $4000.