What Material Is Used For Roof Insulation?
What Material Is Used For Roof Insulation?
Various materials are used for roof insulation, each with its own benefits and drawbacks. Expanded polystyrene (EPS) and polyisocyanurate (PIR) are two of the most common insulating materials used in roofing applications.
EPS is known for its high R-value, or measure of thermal resistance, meaning it is effective at keeping the heat in or out of a building, depending on the season. PIR is also known for its high R-value, as well as its fire-resistant properties.
However, PIR is more expensive than EPS, making it a less popular choice for roof insulation. Oriented strand board (OSB) is another common material used for roof insulation. OSB is cost-effective but not as effective as EPS or PIR when it comes to insulation performance.
OSB comprises many layers of thin wafers pressed together and then dried under pressure, creating a tough, durable material that can be used as a roof deck in conjunction with shingles or metal.
OSB is often used in commercial settings where its high strength-to-weight ratio and durability are desirable characteristics.
The EPS is typically made by combining at least two types of gases with a chemical hardener inside an injection molding machine. This process creates small beads or chunks of foam that are then compressed into sheets for use in roofing applications.
Polyisocyanurate, known as PIR, is made from NCO and Diacron copolymers. Like EPS, the PIR is foamed and then pressed into sheets, which are then cut to size for use in roofing applications. The NCO and Diacron copolymers act as a binder to hold the material together while it cures.
Roof insulation should be considered when determining an R-value for a home’s attic floor. Roof insulation helps to maintain the temperature inside a house by reducing heat transfer through the roof’s air spaces.
Insulating the attic also minimizes moisture problems that can cause mold or rot to form along the ceiling or in wall cavities near insulation.
Adjusting the attic insulation value can ensure that it meets building code requirements and can help to protect your home’s heating, cooling, and electrical systems from harmful heat loss.
The R-value of roof insulation is determined by the thickness of the material and its density. Thick insulations provide more protection than thin or sparsely filled materials.
Insulating the roof may also require replacing shingles or adding a blanket over existing shingles; if you are unsure about what needs to be installed for your roof, contact an HVAC contractor for advice on best practices.
The insulation quality is important because it affects its insulator performance and durability. The R-value of insulation is dependent on the thickness and material density. The higher the R-value, the more effective it insulates.
HVAC contractors can help homeowners calculate what they need and are best qualified to make any necessary adjustments to your home’s attic flooring.
What Is The R-Value Of Polyisocyanurate Roof Insulation?
Polyisocyanurate roof insulation has an R-value of approximately 5.6 per inch. This is a reasonable estimate of the thermal performance of the insulation over the lifespan of a roof assembly, as recommended by the National Roofing Contractor’s Association (NRCA).
Polyisocyanurate roof insulation is a type of insulation that is typically used in commercial and industrial roofing applications. It is made from a rigid foam core sandwiched between two layers of facer material.
The foam core is made from a polyisocyanurate resin, which gives the insulation its high R-value. The facer material can be either foil-faced or paper-faced.
The foil-faced material is typically used in applications where fire resistance is required. The paper-faced material is typically used in applications where moisture resistance is required.
What Is The Minimum R-Value For Roof Insulation?
As of 1987, the National Roofing Contractor’s Association (NRCA) has set the minimum R-value for attic insulation at R-30 nationwide. However, it is recommended that R-values be between R-49 and R-60 in zones 1 through3.
R-values represent the thermal resistance of a material, meaning that the higher the R-value, the better the material is at resisting heat flow. Therefore, the NRCA’s recommendations ensure that homes in all climate zones are adequately insulated against heat loss.