Can you use Earthwool as underfloor insulation?

[Asha8]

I wish to install insulation under my floorboards for warmth. My house is elevated, and immediately below floorboards is the garage and a storage area. Would Earthwool be recommended for something like this? Is there also some material which we can cover the insulation so the underside is not exposed (as we will be walking, and breathing underneath it all the time so concerned about dust and fibres)?

[JacobZ]

Hi @Asha8,

Thank you for your question and welcome to the Bunnings Workshop community, it is fantastic to have you join us.

You can certainly use Earthwool R2.5 90mm x 420mm x 1160mm 5.4m² Insulation FloorShield Underfloor Batts for this application, but you would need to install a sheet material such as plasterboard to enclose them to prevent any airborne fibreglass from causing issues. This is certainly possible, but the cost and increased amount of work required might make you reconsider.

My suggestion is to look at the Expol polystyrene insulation as an option. There are pros and cons, to this product, but it is worth your consideration. As this is a polystyrene product, there is no potential for fibres to become airborne like with Earthwool. The downside to this product is you lose a small amount of R-value, but you can always double it up to gain back that R-value.

These insulation panels are designed to fit snugly beneath your floorboards and can be kept in place with Expol L Bracket Insulation Panel Fixings.

Let me know what you think and if you have any further questions.

Jacob

[projectmumdanni]

Hi we used the silverfloor underlay under the floors under the house. Might be easier and less dustier?

  

[JacobZ]

Hi @projectmumdanni,

Another fantastic option that can help to insulate @Asha8's floor.

This is certainly another product that is worth considering.

Thank you for the recommendation.

Jacob

[johnnyconcrete]

Hi I am a bit confused.

If you can use any earthwool for underfloor insulation, what is the difference between them?  Are we to assume that all earthwools are the same as the underfloor earthwool.?

This would be good as I could use the roll rather than the batts.

Or do the wall and ceiling batts underperform for the flooring?

regards

john

[MitchellMc]

Welcome to the Bunnings Workshop community @johnnyconcrete. It's terrific to have you join us, and many thanks for your question about insulation.

Earthwool R2.5 90mm x 420mm x 1160mm 5.4m² Insulation FloorShield Underfloor Batts are similar to Earthwool R2.5 90 x 430 x 1160mm 7.0m² HD Insulation SoundShield Wall Batts. The difference is that the underfloor has a wind wash barrier to protect from drafts, and the wall insulation is modified to help with sound. 

You could certainly consider a roll rather than batts, though batts are typically used so they fit within the floor joists whereas the rolls would need to sit outside them.

Please let me know if you have any questions.

Mitchell