underfloor heating & insulation

DampCat · 6 Feb 2015 at 01:25

I have UFH in the whole house, although it's zoned. It takes a long time to heat the room to any reasonable difference, several hours. I do live in a wide open apartment with super high ceilings so that probably doesn't help. Running costs are not killing me but I haven't had my post-winter quarterly yet so there's still time.

I don't think I'd have it again. It looks nice in here without radiators but I don't think that's enough. Also I get hotspots on the floor in different places, which is worrying. Luckily I'm renting so I don't care enough to find out why

As for being on 24/7, no way. Mine is on longer than a regular heating system. It's currently 6am-10am, 5pm-10pm. That's set in every zone just for simplicity as I'm not sure if turning off the kitchen,for example, will just make the living room zone work harder (open plan). You have to set it high, mine is set to 28c which is comfortable. The manual says 28 is average. The settings go up to 45 but that sounds pricey.

Edit: I should add I have solid brick walls also, as you do. It's an old mill conversion.

sansnom · 6 Feb 2015 at 11:19

Thanks, I think that's very helpful. We've decided to go with Electric UFH in kitchen and bathrooms which will be kept on 24/7 and is going on top of suspended wood floors.

Will be going with 12x 3500btu radiators for everywhere else.

And finally, will be lifting all floorboards and re-insulating with wool but not insulating external solid walls.

However, something else did come up yesterday which I'm not sure anyone will have the answer to.

Soundproofing Plasterboard for party walls, internal walls, and ceilings OR 2x standard plasterboard around the whole house instead (12.5mm x 2)

Has anyone done this/had experience with it? Does it make sense? It was suggested by the contractor as the soundproofing plaster is £30/board, standard is £7/board

Kimi · 6 Feb 2015 at 12:05

Couple of pics from our UFH, 3 offices and hall. Drilled a hole through the floor so can run it into a panel on the wall downstairs for demonstrations.

Lopéz · 6 Feb 2015 at 12:54

I considered UFH in my bathroom refurb, until I remembered that I really like the feel of cold tiles

DampCat · 6 Feb 2015 at 13:58

sansnom said:
However, something else did come up yesterday which I'm not sure anyone will have the answer to.

Soundproofing Plasterboard for party walls, internal walls, and ceilings OR 2x standard plasterboard around the whole house instead (12.5mm x 2)

Has anyone done this/had experience with it? Does it make sense? It was suggested by the contractor as the soundproofing plaster is £30/board, standard is £7/board

I think it's going to be down to your budget. I lived in a 60's mid terrace for 2 years and i could hear everything from every room (and my neighbours). It didn't bother me too much as I was living with friends and next door weren't too rowdy, even for students (both sides), although at night I could hear my direct room neighbour turning in her bed. So i'd say really it's down to how much you think the cost vs benefit weighs up. If it adds a grand onto a 75k development i'd say do it. If it adds 5 grand, i'd think twice.

Lopéz said:
I considered UFH in my bathroom refurb, until I remembered that I really like the feel of cold tiles

Well you're obviously broken.

sansnom · 6 Feb 2015 at 14:45

DampCat said:
I think it's going to be down to your budget. I lived in a 60's mid terrace for 2 years and i could hear everything from every room (and my neighbours). It didn't bother me too much as I was living with friends and next door weren't too rowdy, even for students (both sides), although at night I could hear my direct room neighbour turning in her bed. So i'd say really it's down to how much you think the cost vs benefit weighs up. If it adds a grand onto a 75k development i'd say do it. If it adds 5 grand, i'd think twice.

Thanks DampCat

I will definately be going down the route of sound minimisation as I hear everything and it drives me nuts. My question was more focused around whether using a single board of 'soundproof' plaster is more effective than using 2 boards of regular plaster?

Contractor seems to think that soundproof plasterboard is a gimmick and doesn't help at all. He recommended putting 2 regular plasterboards on top of each other for each wall which he says would be cheaper by 50% and more effective.

I've not had experience with either so I'm not too sure?

DampCat · 6 Feb 2015 at 15:19

Oh me either, that's way out of my league i'm afraid. Lets wait for maccapacca to respond, that's more his department.

I'd say trust the contractor though. If he says the cheaper way is better i'd believe him, as they're usually asking for MORE not less

PlacidCasual · 6 Feb 2015 at 15:30

In an old solid wall house internal insulation seems like a good idea but you really need to get the details right. Cold bridging particularly at floor beams can cause condensation and rot building up problems in long term. Under floor heating will lose a pot of heat into the earth unless you have significant insulation which is why it's great for Eco new homes poor to retrofit.