Gypsum Roof Deck R Value

For example two inches of extruded polystyrene with an r value of 11 has an rsi of 1.

Gypsum roof deck r value.

As we said before the r value measures the thermal resistance of a material. These fibrous decks generally have a gypsum like or cementitious binder and combine the functions of a roof deck thermal insulation and finished ceiling. The u value includes the thermal resistance values for roofing and both inside and outside air films in addition to the insulation material. They also have acoustical value and are oftentimes used in schools and restaurants.

1 4 dens deck roof board. Referred to as meps can have an r value that will vary from less than 4 00 to slightly more than 4 00. You should of course see the manufacturer provided technical data sheet for the r value of specific products. Does not consider directions of heat flow up or down nor winter summer conditions.

Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials. The r 0 87 value for the first value in this air r value table subsection. The tables show a u value r value and c value for several thicknesses of siplast roof insulation systems. Does not consider internal convection effects.

Extruded expanded polystyrene insulation is. 40 178 weights nom. For a very good introductory overview article on r value see r values over at the website of. Does not consider presence absence of reflective barriers.

R values 28 tested in accordance with astm c518 spannings. For instance if you have a material with an r value of 12 attached to another material with an r value of 3 then both materials combined have an r value of 15. R value of building materials material r inch r thick ness fiberglass inch 3 00. R value of various materials.

R value is used in the united states. Densdeck roof boards can replace any generic type x gypsum board in any roof assembly in the ul fire resistance directory under the prefix. Gypsum board drywall inch 0 45 inch 0 56. Carpet fibrous pad 2 08 rubber pad 1 23 roofing materials asphalt shingles 0 44 wood shingles 0 97 windows single glass 0 91 w storm 2 00 double insulating glass inch.

1 4 spans flute widths up to 2 5 8 flexural strengths parallel lbs. To convert rsi to r value multiply the rsi by 5 67826. To convert the r value of a specific thickness of a material to rsi divide the r value by 5 67826.