Rigid Insulation R Values Roof

When it comes to insulation performance the difference is in the details.

Rigid insulation r values roof.

Know exactly how much you need with our project calculators. R panel is manufactured with a closed cell polyisocyanurate foam core bonded to fiberglass reinforced facers and designed for use over metal nailable and non nailable roof decks with a variety of membrane systems. Steep slope or pitched roofs will almost never include insulation as a part of the roof assembly. When determining how much insulation you need don t guesstimate calculate.

R value is used in the united states. The r value you have to achieve will be a big part of figuring out the type and thickness of the insulation you will install. With premium polyiso manufacturing atlas is able to produce the highest effective r values with minimal material thickness. For example two inches of extruded polystyrene with an r value of 11 has an rsi of 1.

R value measures how well certain building insulation materials can resist heat. For a 1 in thick panel may vary based on region standard r value of r 5 8 per inch the manufacturing process starts with liquid foam not recyclable has to be sprayed against a substrate to form a rigid panel so all iso panels are faced. Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency. Rsi r value système international is the metric equivalent.

Rigid insulation is usually made up of fibrous materials or plastic foams. The r value for foamular xps insulation is provided from testing at two mean temperatures 40ºf and 75ºf and 180 day real time aged as mandated by astm c578. The r value at 180 day real time age and 75ºf mean temperature is commonly used to compare products and is the value printed on the product. Rigid insulation r value by comparison usually ranges from r 4 0 to 6 5 and may get as high as r 8 7 depending on the insulation material.

Traditional loose fill insulation such as fiberglass or cellulose has an r value between r 2 0 and 3 5 per inch of thickness. The lttr a 15 year time weighted average r value is largely affected by thermal aging where air diffuses in and blowing agent diffuses out of the foam. To convert the r value of a specific thickness of a material to rsi divide the r value by 5 67826. The higher the r value the greater the insulation performance.

All products in the acfoam polyiso roof insulation family are closed cell rigid foam insulation board flat or tapered. Most often used in roofing applications average cost of 70 per sq.