Roof Thermal Insulation Values

A rigid roof insulation board with high thermal efficiency johns manville r panel is compatible with multiple types of membrane systems.

Roof thermal insulation values.

An insulating material s resistance to conductive heat flow is measured or rated in terms of its thermal resistance or r value defined as ft f hr btu. Regardless ashrae s new above deck roof insulation standard is a good place to start as it jumped 33 percent from r 15 to r 20 in five of six climatic regions. Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency. Recommended insulation levels for retrofitting existing wood framed buildings.

Existing 3 4 inches of insulation. The higher the r value the greater the effectiveness of the insulation. Achieving greater r values in exterior walls. The r value depends on the type of material its thickness and its density.

Ultimately selecting which product and value to use depends on many factors particularly thermal load. 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. May not be left exposed in living area. Or square feet degrees fahrenheit hour btu.

Or area temperature difference time heat loss. Design r value refers to the r value intended for the building or sub component such as the roof assembly by the architect or other design profes sional. The higher the r value the better the thermal performance of the insulation. The effective r value refers to the insulation value that is actually achieved.

Tem thermal insulation values caused by attachment methods commonly in use in the roofing industry. Tapered polyiso minimizes the negative effects of ponding water and extends the service life of a roof. Very good air bypass leak sealing properties. It can also be referred to as an overall heat transfer co efficient and measures how well parts of a building transfer heat.

In simple terms r values measure the effectiveness of insulation and a higher number represents more effective insulation. This means that the higher the u value the worse the thermal performance of the building envelope. Aging effects comments. Carlisle s tapered insulation helps promote rooftop drainage while providing excellent insulating value.

A u value is a measure of heat loss in a building element such as a wall floor or roof. Icynene foam to mineral wool insulation. Add insulation to attic. Insulation or other building material 9.