Hvac Insulation R Value

Additional r value for a masonry wall constructed using these materials needs to add the insulating value of additional wall components typically included such as 1 solid foam polyisocyanurate r 8 extruded polystyrene r 5 expanded polystyrene r 4 or 1 of perlite r 2 7 and for an exterior air film winter no wind r 0 17 an interior air film again no air movement r 0 68 3 4 of.

Hvac insulation r value.

Some other factors to consider. 6 305 btu hour 0 53 ton r 4 2 duct insulation. If the c value is 0 5 then the r value is 2 0. 7 948 btu hour 0 66 ton the numbers are even higher for the additional heating load.

The duct insulation r values i mentioned above are what s on the product label. In fact there is almost no difference between these documents when it comes to mechanical insulation for hvac systems. But insulation r value differs significantly from one material to another. R value 1 c value.

For any applications claiming r values reflective insulations must face at least one open airspace cavity or be installed within an enclosed air space without free air flow. When calculating r value for several layers of insulation you simply add their r values together. For example for a particular type of insulation board a 2 inch thick board will have twice the r value of the 1 inch thick board. Rigid insulation such as plastic foam can run from r 3 5 to 8 0 or higher.

For most applications a rating of r 6 or better will provide the best efficiency and long term cost effectiveness. Purchasing the ducting and the insulation separately is often more cost effective and has a greater variety of options when it comes time to choose the r value of your insulation. R value thickness k value. Aerogel has an r value of about r 10 0 and vacuum insulated panels top the list with an astonishing r value of r 30 0 or higher per inch of thickness.

The real value of improving u values we asked mott macdonald to research the energy saving and roi from specifying extra insulation versus doing the minimum and complying with local regulations. When referring to the u value of a building the r value of all its different components will be considered. In the context of building and construction the r value is a measure of how well a two dimensional barrier such as a layer of insulation a window or a complete wall or ceiling resists the conductive flow of heat. The requirements for insulation on pipes and ducts supporting an hvac system are outlined in both ashrae 90 1 and the iecc.

One can calculate it from the equation for c value in equation 1 above. For example an inch of loose fill fiberglass has an r value. If we look at it in terms of how much insulation your home has in various areas the attic walls or floor r value is a way to think about how much heat loss or heat gain in summer your home is experiencing in any given area. R value is the temperature difference per unit of heat flux needed to sustain one unit of heat flux between the warmer surface and colder surface of a barrier under steady state.

Loose fill insulation such as fiberglass or cellulose usually has an r value ranging from r 2 0 to 3 5.