How to add underfloor insulation?

[Jonathan07]

The house we are renovating has no underfloor insulation. Should I rip off all the timber floors and do the insulation or just install engineered timber on top the existing timber floors?

[EricL]

Hello @Jonathan07 

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about underfloor insulation.

Would it be possible for you to go under the house to install the insulation? This would be more ideal than ripping the floor off just to install insulation in the floor. Unless your plan actually involves removing the current flooring and replacing it with a new one then it would be easier to install the insulation from the top. 

Engineered flooring will provide insulation. Because it is made from layers of real wood, it naturally has lower thermal conductivity than materials like tile or concrete. This means it helps retain warmth, making the floor feel more comfortable underfoot in cooler conditions. But will not compare to the insulation provided by flooring batts.

Here is a handy step-by-step guide: How To Install Underfloor Insulation Batts 

Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.

If you need further assistance, please let us know.

Eric

[Nailbag]

Hi @Jonathan07 

Do you live in an exceptionally cold region and/or is your home subject to cold breezes under the floor? I only ask as it relates to why the need to insulate at all?

And if you do need to, I definitely wouldn't be lifting the floor to do so as thats a very substantial expensive project, for potentially not a massive benefit. As @EricL suggested the way to go is from under the floor using foam bats that push securely into place with some trimming.

I had a coastal home some years back with all tiles in the living space. They were so cold on your feet in winter, I had to squeeze under a 400mm subfloor space to insulate. It was a fun job, but did help. Thought not as well as hoped. If I stayed there longer I would have floated a floor on top.

Nailbag

Nailbag

[Dave-1]

Good afternoon @Jonathan07 

The first question that comes to mind is do you have acess to under the fllor space? It would be a very expensve project to rip up floorboards.

Depending on the location of where you live is what i would ballance out the "need" for insulation under the floor, the manufactured boards will give some insulation as @EricL has said tho not as much as @Nailbag has described. Things such as rugs and furniture will aslo change how the cold is transfered through from underneath. When I bought a house someone once siaid "wait for a years worth of seasons" before making big changes. I know its a high priority to rush in and get things done but sometimes seeing how things are may change the urgency.

I like the idea of an engineered floor and rugs compared to retrofitting under the floor, unless acess is easier then 400mm That would have been fun/not fun.

Dave

[Jonathan07]

Unfortunately, there is no roof for underfloor insulation. I might have to rip all the timber floors to get insulation done then. I am not sure what sort of flooring will be done afterwards instead of the timber. It just too hard to decide. 

[EricL]

Hello @Jonathan07 

Is this flooring area under cover or it exposed to open weather? Can you please share a photo of the flooring area? This will definitely help us give you better advice.

If you do decide to remove your existing flooring in order to install insulation, I propose looking at STRUCTAflor 19 x 3600 x 600mm General Purpose YellowTongue to cover your floor and have HanWood 5mm Aquila Sands SPC Hybrid Waterproof Flooring or similar to go over the top. But if you prefer engineered flooring that is an option as well. There are options open to you, but it all depends on the budget you've set aside for this project. This is on the condition that the flooring is covered and is not exposed to the open.

Will you be doing the floor tear out yourself or are you hiring someone? Who will be responsible for installing the floor covering over the frame? What type of materials do you plan to use, and what will the final flooring finish be on the surface? These are just some of the things you'll need to take into consideration when doing your flooring project. 

If you have any other questions we can help with, please let us know.

Eric