Retrofit UFH

[craigap]

We are currently looking at carry out some improvements in our 7year old new build semi detached home, namely new flooring (Kardean or similar), remodeling the kitchen and a few other bits and pieces.
One thing I always wished was that we installed UFH to the ground floor when the house was being built, but wasn't really an option at that point.
The house has a standard poured concrete floor, measuring around 52m2, however with utility, kitchen units, etc taken in to account, we are at around 40M2 consisting of kitchen lounge, WC and hall way.
I've looked at a few wet retrofit systems and feel that we have the height to accommodate say a 20mm high system plus flooring, plus we have a relatively new 30KW combi boiler that is easy to access for pipework.

I understand the installation costs are going to be quite significant and am happy with these as I would 1st fix myself then handover to my plumber for pressure testing and commissioning, however I would like to know if anyone else has fitted a similar system and found it to be any good or efficient before I commit any further?

Any help or advise appreciated,

Craig

 

[fixitflav]

We are currently looking at carry out some improvements in our 7year old new build semi detached home, namely new flooring (Kardean or similar), remodeling the kitchen and a few other bits and pieces.
One thing I always wished was that we installed UFH to the ground floor when the house was being built, but wasn't really an option at that point.
The house has a standard poured concrete floor, measuring around 52m2, however with utility, kitchen units, etc taken in to account, we are at around 40M2 consisting of kitchen lounge, WC and hall way.
I've looked at a few wet retrofit systems and feel that we have the height to accommodate say a 20mm high system plus flooring, plus we have a relatively new 30KW combi boiler that is easy to access for pipework.

I understand the installation costs are going to be quite significant and am happy with these as I would 1st fix myself then handover to my plumber for pressure testing and commissioning, however I would like to know if anyone else has fitted a similar system and found it to be any good or efficient before I commit any further?

Any help or advise appreciated,

Craig

Discussed recently on this thread https://www.diynot.com/diy/threads/floors-dug-up-should-we-put-in-underfloor-heating.587983/

 

[craigap]

Discussed recently on this thread https://www.diynot.com/diy/threads/floors-dug-up-should-we-put-in-underfloor-heating.587983/

Thanks Fixifflav, I have had a good read through the thread and although it discusses UFH in general, I was hoping for views specifically on retrofit. I understand UFH isn't for everyone and wont necessarily make huge energy savings, but its the comfort factor I was more interested in, of traditional screened in versus retrofit.

 

[fixitflav]

Thanks Fixifflav, I have had a good read through the thread and although it discusses UFH in general, I was hoping for views specifically on retrofit. I understand UFH isn't for everyone and wont necessarily make huge energy savings, but its the comfort factor I was more interested in, of traditional screened in versus retrofit.

OK, from that thread it seems UFH is likely to be more economical on gas (can't say more efficient after winston1's latest post!), but I've no personal experience.

 

[Madrab]

Given your situation then your options are very restricted really. A low profile overlay system would be 1 option .... it consists of a 22mm EPS400 foil lined Poly former that carries the wet pipework and the rest of the system is as per normal UFH systems, from the manifold assemblies to the stats etc.

Another option is channeling the current slab and then screed on top but at 20mm that isn't that thick a top and do you know how well insulated it is?

I have retrofitted my own downstairs (as a test case) and retrofitted another 3 clients to date with the Poly overlay system with real wood/tiles and currently experimenting with 6mm no more ply and then a carpet top.

The feedback I have received is very good and speaking from my own experience I have found the system to be much better at heating the space than the old system and has been cheaper to run.

 

[craigap]

Thanks Rob.
I noted your comments in another thread and was ideally after the likes of your self commenting.
One of the systems I looked at was almost like an open crate plastic system, which claimed to have very quick heat up time despite no insulation, but I can't see why we wouldn't use a proper insulation board like you stated. There just seems like such a myriad of choices, but it looks like most are narrowed down by subfloor and floor finishes.
From what I recall, the floor is a 100mm concrete pour, with Kingspan insulation boards below that. Can't recall what's below that, but seem to think a further concrete pour.
If there wasn't a huge difference in heat output, I would rather go with an overlay system and avoid all the mess of channelling, not to mention the time. Also the floor fitters have already said they would need to put a screed down on the current floor.
For myself, its more of a comfort factor and even heat distribution and seeing as we are investing so much in to the floor finish it just made sense to do it.
With having two rooms plus a hall way and WC, do we need different zones or are they fine on one, as they are currently not individually controlled via the combi?

Craig

 

[Madrab]

One of the systems I looked at was almost like an open crate plastic system

That would require a screed poured once the UFH was down, the concern with yours is the height you have to play with. A screed has a min depth to avoid cracking and breaking up. What that depth recommended is usually down to the manufacturer and what type of screed is being used.

If the areas are separate then zoning each area would probably be better for tighter temp control.