Insulating Floor Trusses

Kingspan s new range of vacuum insulated panels vips offers an interesting solution for those needing an ultra thin build up.

Insulating floor trusses.

4b slab floors built directly on the ground. 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. You can insulate second floor rim joists following the same steps shown here if you happen to tear out a ceiling during remodeling. Also insulate 4a any portion of the floor in a room that is cantilevered beyond the exterior wall below.

The inspector may require you to cover the new insulation with drywall as a fire block or leave some areas uncovered to allow for termite inspections. Rigid foam is the best insulation for rim joists. In some cases if the floor is accessible from below it may also be possible to partially insulate the joists from underneath which offsets thermal bridging through timber members but this is not often the case. Installing roll insulation in ceiling of basement which is under floors of living space my basement is heated but a smaller amount than up in living space usually 66 68 upstairs and 58 60 at the same time in basement my question is about the kraft paper facing i think it should face the basement because of any moisture in basement.

Joist bays the open spaces between floor joists are prime hosts for insulation under specific circumstances. The fiberglass will also need to be secured in place using wire mesh twine wood laths or other securing methods which can be an intensive project that adds to the overall cost. 4d extend insulation into joist space to reduce air flows. Kingspan vips offer an ultra thin build up of just 26mm image credit.

The insulation should press right up against the floor between joists. Kingspan installing insulation on top of the floor can present problems with ceiling door and window cill heights. Gaps between the insulation and the floor can lead to inefficiency and heat loss. 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.

I have 18 open web floor trusses installed in a unconditioned garage with a conditioned room planned for above. Foam flash batt blown cellulose fiberglass sprayed rock wool and fiberglass batts. Yes it s expensive but as soon as you have you re trusses in and sub floor down you could insulate and leave it exposed until you get to the garage ceiling. Would greatly appreciate the collective advice from the readers of gba on the following.

This stuff forms a great vapor barrier as well so you ll eliminate drafts from the cold space below and any possibility of carbon monoxide getting into the apartment if people are warming up cars even with the garage door open. 4c as an alternative to floor insulation foundation walls of unvented crawl spaces.