Best Loft Floor Insulation

4 trim lengths of paper backed insulation so they follow a joist bay from one rim joist to the one opposite.

Best loft floor insulation.

The insulation should press right up against the floor between joists. A semi rigid material is generally best as it can be cut very slightly oversized and squeezed in between the floor joists thereby ensuring no draught causing gaps. It s generally the cheapest option and good all purpose insulation especially for between joists. If you want to insulate a floor assembly by leaving the joist bays empty and installing rigid foam on the underside of the joists here are a few things to keep in mind.

According to the 2012 irc the minimum r value for floor assemblies is r 13 in zones 1 and 2 r 19 in zones 3 and 4 r 30 in zones 5 and 6 and r 38 in zones 7 and 9. Best seller owens corning thermafiber fire and sound guard mineral wool insulation batt 15 in. The most expensive option. Save 60 50 10 544 50 pallet 605 00.

Save 60 50 10. The insulation should be pushed tight to the underside of the floorboards. This is to prevent the joist. You can still board directly on to the joists if you want but it is worth noting that this would not pass a building control inspection because you wouldn t have the full 270mm depth of insulation required by regulations.

At least 25mm of the joist must be left exposed to ensure air circulation. It is the longest lasting and the highest r value insulation that can be put into place. Fiberglass rolls can be placed between joists but the fiberglass itself will need to be cut to fit properly between joists. Foam in place insulation is sprayed into spaces between the joists and goes around venting pipes and electrical work.

View the owens corning 2x6 wall floor insulation 544 50 pallet 605 00. Find your zone on the map and then use the above insulation r value chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces. Gaps between the insulation and the floor can. The most common form of loft insulation this comes in rolls of rock glass or mineral fibre we use earthwool by knauf which is a really good environmentally friendly option or else foil backed felt.

The best solution is to build a raised loft floor above the insulation details of which are shown below. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. Fiberglass insulation is usually the best option though handling fiberglass can be dangerous and it is not the most eco friendly option in some cases.