Recommended Insulation Depth For Attic

Mary previously had 100mm of fibreglass insulation in her attic but decided to upgrade the insulation in her attic to the required 300mm following consultation with the seai and various contractors.

Recommended insulation depth for attic.

Your attic should have a certain amount of insulation in it and the recommended level of insulation for your attic is dependent on where you live. For example if you have a type of insulation that has an r value of r 5 per inch of thickness you will need a depth of 6 inches of this insulation installed your attic to reach r 30 if you live in zones 2 or 3. Insulation materials run the gamut from bulky fiber materials such as fiberglass rock and slag wool cellulose and natural fibers to rigid foam boards to sleek foils. Add the right kind of insulation.

Bulky materials resist conductive and to a lesser degree convective heat flow in a building cavity. Once you ve decided which type is best for you examine the material options and prices to home in on the right product. For diy attic insulation you ve got two choices. R value is a measure of insulation s ability to resist heat traveling through it.

Attic insulation using fiberglass mary has a four bedroom detached house 150m2 in size. If you are insulation a virgin loft the easiest way is to roll 100mm thick insulation between the joists. The higher the r value the better the thermal performance of the insulation. For loose fill cellulose this translates to a total depth ranging from 8 inches.

The higher the r value the better the thermal performance of the insulation. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type. Once this layer has been laid then lay 170mm insulation across the top of the joists at 90 degrees to the joists. Insulation levels are specified by r value.

In temperate coastal areas such as zone 3 attic insulation of at least r30 up to a maximum of r60 is recommended. R value is a measure of insulation s ability to resist heat flow. Insulation level are specified by r value. Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.

The reason for this is that the insulation manufacturers are trying to make it easier to hit the 270mm thickness sweet spot. Rigid foam boards trap air or another gas to resist conductive heat flow. Find your zone on the map and then use the chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces. She has an annual heating bill of 1 600.

Recommended home insulation r values. Loose fill or batt the common term for blanket insulation. Both can be added to uninsulated attics or layered over existing material.