should be able to check that floor complies with standards V
ht
a 1985 build would suggest you are optimistic on walls/windows
Retrofit wet UFH
- Thread starter NoNameNoNumber
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A quick calc suggests our floor is 0.785 W/m²K
Which looks to be some attempt at compliance circa ~2000 when it was built
I used https://www.jk-gb.com/ to retrofit wet UFH in my refurb. They chased into the screed - did a great job.
You could talk to them about your floor construction and see what they recommend.
You could talk to them about your floor construction and see what they recommend.
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I've been considering the retrofit option, but reading around people seem to state that you lose too much heat downwards without at least 100mm Insulation. Has anyone actually fitted the retrofit methods (On slim insulation boards or milling the existing concrete slab for the pipes) and can comment on how it has performed since installing it? I can see some here are in the process of doing it, but no one who has done it and posted how they find it...
Caporegime
Retrofitting it honestly seems like more hassle than it's worth. Is wet ufh really that much better than modern rads?
Associate
Yes its like night and day particularly if you have hard flooring like tiles etc.
We had it since our last house and i would not go back to a house with radiators.
Agreed, it's a huge upgrade.
I've done my entire house and used this company (they're vaguely local to me but cover the UK), I'd recommend them if one of their products fits your needs: https://www.underfloorheating.co.uk/
Downstairs is approx 130 m2
Cost of channeling, manifold, pressure testing and flex seal over the pipes was almost 4k.
I was replacing a warm air fed system, so i had no pipes or rads in the house.
I would say, who are these people and what is there experience/skillset
I wouldn't route into a slab if it's uninsulated, but if it's raised up off the ground and has some insulation in there then it's not that bad. Remember air is a good insulator.
Most importantly you really need to do a proper full house heat loss survey and work out the ideal ufh/rad combo, flow temps, dT and configuring your heating system (boiler or ASHP) to work correctly for the home heat loss.
Ideally any ufh system will be run open loop or with as little individual zones as possible. Multiple room stats, hives, tados and all that with pumps and manifolds split up everywhere is not smart.... Just the illusion of smart and very inefficient.
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I’ve just given these guys a call.
16mm deep channel with 14mm pipe at 125mm centres ~ 100w/m^2
Which is 50% more than the retrofit kits. And far less complicated to fit.
I’ll send my floor plan over to them to quote up.
Thank you Paz
Looking more and more at wet UFH, was on the list of things to do this year, but starting to research more now. House was built in 1969, so sits on a currently uninsulated suspended floor. My plan currently looks something like this.
Initially insulate under the lounge floor 6x4m with 100mm Celotex between joists, this room won't be UFH as it has 2 big wall rads and wall mounted aircon, and generally is quite comfortable once up to temp.
Then I will will be looking to do the Kitchen and sitting room which is a 9m x 3.5m space, again insulating with 100mm celotex, as the kitchen is in place and i'm not planning on removing all the units, i'll be pulling up the floorboards in the middle of the room and getting under the floor to get the celotex under the existing floorboards, edging them with gapotape, will then lay UFH in a dry screed in between the joists in the middle of the room at 60-70mm depth, which is about 2m wide. and then overboarding with ply/chipboard before putting down new LVT.
Depending on the success of this I may look at doing the hallway, but potentially I may just insulate this area. I will also look at the Dining Room (was conservatory, but now has PIR cold roof with proper insulation) but as this sits lower than the kitchen I believe this is just a concrete base so I may just leave this as the single rad keeps it fairly warm.
This will be run off a standard gas combi boiler, and the kitchen/lounge area only has one large double rad so is massively underheated currently and struggles to get above 19c most of the winter, which means it's not used as much as we'd like.
Initially insulate under the lounge floor 6x4m with 100mm Celotex between joists, this room won't be UFH as it has 2 big wall rads and wall mounted aircon, and generally is quite comfortable once up to temp.
Then I will will be looking to do the Kitchen and sitting room which is a 9m x 3.5m space, again insulating with 100mm celotex, as the kitchen is in place and i'm not planning on removing all the units, i'll be pulling up the floorboards in the middle of the room and getting under the floor to get the celotex under the existing floorboards, edging them with gapotape, will then lay UFH in a dry screed in between the joists in the middle of the room at 60-70mm depth, which is about 2m wide. and then overboarding with ply/chipboard before putting down new LVT.
Depending on the success of this I may look at doing the hallway, but potentially I may just insulate this area. I will also look at the Dining Room (was conservatory, but now has PIR cold roof with proper insulation) but as this sits lower than the kitchen I believe this is just a concrete base so I may just leave this as the single rad keeps it fairly warm.
This will be run off a standard gas combi boiler, and the kitchen/lounge area only has one large double rad so is massively underheated currently and struggles to get above 19c most of the winter, which means it's not used as much as we'd like.
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Morning Guys,
We're going down the route of machining the floor screed for ufh pipes to be laid in. I've been told the mixer will control water flow to 30ºC but looking at the LVT, we're being told it'll only take 27ºC.
Are other LVTs available that will take a little higher?
We're going down the route of machining the floor screed for ufh pipes to be laid in. I've been told the mixer will control water flow to 30ºC but looking at the LVT, we're being told it'll only take 27ºC.
Are other LVTs available that will take a little higher?
Associate
Are you having a screed put on top or just laying the flooring directly over the pipes
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Levelling compound over pipes, then flooring.
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I’ve lifted some LVT. The contact adhesive that remains, does that need to be taken up too before JK come? Any tips on doing this?
@NoNameNoNumber - Did you end up going through with retrofitting Wet UFH heating in the end? How was/is it? Considering doing the same...