UFH in slab - info for our builders?

[Onoff]

Have a look here at the bottom of the link at the installation bit if you want to add legitimacy to the idea. I used the red Polypipe panels btw as did I think @PeterW

Not sure if I would again as I reckon I'm au fait enough now to clip straight to the pir but it's damn quick and easy! Pretty cheap too.

 

https://www.polypipe.com/housing/polypipe-underfloor-heating/solid-floor-systems

[Oz07]

@Roz how has this progressed? Any pressure tests since installation. As an aside, how come dpm detailing is so finicky then you can go and bang ufh staples in?

Edited September 19, 2019 by Oz07

[Nickfromwales]

  On 19/09/2019 at 19:28, Oz07 said:

@Roz how has this progressed? Any pressure tests since installation. As an aside, how come dpm detailing is so finicky then you can go and bang ufh staples in?

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The UFH staples tend to stretch the DPM and then it still seals tight-ish to the staple. Not ever had an issue, but with liquid screed they put a much thinner ( 1200 ) membrane over the lot to keep it leak free. With concrete it's not as much of an issue as the water tends to separate out and the concrete stays put. 

[wardie9025]

Just about to push the go button on a retrofit UFH in the slab.....any follow up experience/comments as its been a few years since these works were done??

 

Any and all input very much appreciated!

 

Gaz

[Roz]

  On 03/06/2023 at 09:07, wardie9025 said:

Just about to push the go button on a retrofit UFH in the slab.....any follow up experience/comments as its been a few years since these works were done??

 

Any and all input very much appreciated!

 

Gaz

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I mean we have had no issues with ours, ufh has been running fine and no issues as far as I know 😂 . Hope yours goes / went ok!

[HughF]

This was ours, a little over 10days ago. 
 

125mm concrete, on 240mm pir.

 

puffed it up to 5 bar for the pour.

 

I would have preferred to use pex-Al-pex, but I didn’t have quite enough in stock and I was battling against time on this one, my wife and I threw it down after work one evening. That’s continal pe-rt, in 16mm.

 

My builders did theirs in slab too, I think the accepted wisdom is changing nowadays.

Edited July 6, 2023 by HughF

[gavztheouch]

I’m planning on doing heated structural slab it’s about 7m by 15m 250mm deep in an isoquick foundation system. Did you guys have to put control joints ie shallow cuts in the slab to prevent cracking in unwanted places?

Edited September 14, 2023 by gavztheouch

[flanagaj]

  On 22/02/2019 at 15:49, recoveringbuilder said:

Ours was put in on the mesh and pipes were pressurised at the time, so mesh was sat 50 mm up on little holding things then pipes attached to mesh then the pour

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Thanks for this.  Makes much more sense doing the slab this way.  Did the contractors who did the slab also power float it?

 

[recoveringbuilder]

  On 24/02/2024 at 20:00, flanagaj said:

Thanks for this.  Makes much more sense doing the slab this way.  Did the contractors who did the slab also power float it?

 

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Yes 

[flanagaj]

What was your cost/M2 for the concrete poor and power float?

Edited March 5, 2024 by flanagaj

[LiamJones]

We went self compacting concrete, no power floating required. £150/m3 for the concrete (TopFlow). £1100 for the install. 100m2 @ 100mm = £2600 ex vat installed.

[Tom]

We had a 170m2 200mm slab put down and powerfloated with a graphite coloured dry shake on the top, came in at about 4k ex-vat IIRC.