Replace suspended with solid?

[damessiahuk]

Bear with me... It's a long one. I'm looking at options for reinstalling UFH throughout my house

 

I installed TorFloor2 UFH system as structural floorboards as I couldnt build up the floor any further, and also my joists were too shallow (100mm) to notch UFH pipes+insulation+biscuit mix etc

 

Once I had then put ply and lvt covering over the boards, the system was really ineffective and hardly any heat made it through, similarly, despite insulation I think it lost a lot of head below. I regretted it but had to live with my decisions.

 

Fast forward, house massively damaged by fire and the TorFloor2 has to come up and be replaced. I now have my chance to do something different - and I want the end result to be a really effective UFH system in the house. 

 

Would welcome thoughts on options:

 

1) keep suspended floor but replace the joists with bigger joists to allow pipes notched through and a biscuit screed mix on top of PIR . This seems to be the preferred and more effective approach for Ufh on suspended floor to avoid build up/spreader plates.

 

How easy would it be to widen the joists to say 300mm?

 

2) same as above but install a block and beam system? Instinct tells me the blocks would help with thermal mass but probably no additional benefit other than structurally stronger 

 

3) rip it all out and replace with a concrete slab and embed UFH into the concrete with insulation. I may even opt for a polished concrete finish to avoid any additional build up and flooring.

 

The only other factor is I'm also converting my garage into a room so this will need a subfloor installing - therefore just filling the entire ground floor with concrete is appealing to have it all one level.

 

The entire area is about 100sqm

 

The depth of the cavity under the floor is around 40cm

[Redbeard]

Option 3. Do most of the garage fill with EPS, depending on relative cost of conc vs EPS.

[damessiahuk]

My ignorance, What's EPS?

[Nickfromwales]

46 minutes ago, damessiahuk said:

My ignorance, What's EPS?

Expanded PolyStyrene   
 

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