UFH no go areas

murphaph

Water John wrote: »

There should be NO joints under the floor. You can put flexi pipe over the pipe going through doorways, since the floor in each room is floating.

If using a high heat source eg condensing boiler, you must use at mixing manifold with pump attached. The water going into the floor must be NOT greater than 40 C.
A low source eg heat pump, can supply water directly through a simple distribution manifold.

No joints in the pipe of course, but the screed should have expansion joints if the area is large enough to warrant them and they should be included at door thresholds.

As you say, high heat sources must be mixed down, but my point was not about the manifold (which is accessible and can be altered later) but about the pipe in the screed. This should be laid so that a low temp heat source can be installed later. This means max pipe centres of 150mm, preferably 100mm. If the centres are up at 200 or even 300mm this will never work efficiently with a heat pump as you'd have to have the flow temp so high that the heat pump would be operating terribly inefficiently.

Water John

Agreed Murph, 150 mm is fine. Some installers going 200mm, don't agree with it. Possibly OK up stairs.
Would have recommended 100mm by large glass in the past, but the U value of glass has improved a lot.

BarneyMc

murphaph wrote: »

No joints in the pipe of course, but the screed should have expansion joints if the area is large enough to warrant them and they should be included at door thresholds.

Is it the liquid screed installer who's responsible for the expansion joints?

Got my UFH pipes all installed on the ground floor. Upstairs tomorrow!

Water John

I think that would be the plumber. A lot of them don't do them. In fact I would say rarely. then, this is Ireland.
Neither have I heard of any leaks or cracks.

Good work Barney. Just interested to know is it multiplex or pex-al-pex pipe.
Just nosey, it doesn't matter which was used.

murphaph

BarneyMc wrote: »

Is it the liquid screed installer who's responsible for the expansion joints?

Got my UFH pipes all installed on the ground floor. Upstairs tomorrow!

In our case the pipe layer installed the expansion joints in our concrete screed. Maybe you can get away without them with liquid screed?

hexosan

UFH lads installed the flexible covers on the pipes at the threshold for me. You need expansion joints even with liquid screed. They (liquid screed) placed expansion strips across all the thresholds they also added reinforcing mesh around the bottoms of the stairs, on 90 degree corners, crossing over RSJ's and anywhere else they thought it was needed.

BarneyMc

Water John wrote: »

I think that would be the plumber. A lot of them don't do them. In fact I would say rarely. then, this is Ireland.
Neither have I heard of any leaks or cracks.

Good work Barney. Just interested to know is it multiplex or pex-al-pex pipe.
Just nosey, it doesn't matter which was used.

I'll enquire about the expansion strips today with all involved. No idea about the pipes but will have a gawk today.

delfagio

Water John wrote:

Good work Barney. Just interested to know is it multiplex or pex-al-pex pipe. Just nosey, it doesn't matter which was used.

The pipe I used was multi-layered pex-Al-pex. Not to easy to lay as its slower than the flexible UFH pipes. Laid it all myself so had sore fingers from all the bends

I used it for all my plumbing,

Screed company I used installed expansion joints at all doorways.

rampantbunny

Bonzo Delaney wrote: »

I done the wet room shower areas I just cased around the area where the tiled joint would be then poured the floors as normal after it was safe to walk on the floors took out the case then poured the dished floor in the shower areas afterwards. Worked out perfect no cold spots in the walk in shower

Are your UFH pipes run over and back across the joint between the shower tray area and the rest of the floor, or did you enter the shower area only once, loop around inside, and exit once?

If crisscrossing over and back and you later wanted to mechanically fix a shower door/screen to the floor you run the risk of piercing pipes unless accurate measurements were taken.

Interested in how you did this as I'll be getting UFH pipes down in week or two and plan on running UFH to shower areas also.

BarneyMc

rampantbunny wrote: »

Are your UFH pipes run over and back across the joint between the shower tray area and the rest of the floor, or did you enter the shower area only once, loop around inside, and exit once?

If crisscrossing over and back and you later wanted to mechanically fix a shower door/screen to the floor you run the risk of piercing pipes unless accurate measurements were taken.

Interested in how you did this as I'll be getting UFH pipes down in week or two and plan on running UFH to shower areas also.

Leaving shower areas a no-go areas. Will post photos soon though so you can see.

BarneyMc

Just had a look upstairs and some of the 25mm floor insulation is lifting at the wall junction with the perimeter insulation. I suppose jamming it tight with very thin strips might do the trick or go around later with an adhesive and leave a weight on top over night?

Also, there are some very small gaps around some of the pegs where they fix to the floor insulation. Would it be a good idea to tape the worst of these before liquid screed is poured next week?

hexosan

BarneyMc wrote: »

Just had a look upstairs and some of the 25mm floor insulation is lifting at the wall junction with the perimeter insulation. I suppose jamming it tight with very thin strips might do the trick or go around later with an adhesive and leave a weight on top over night?

Also, there are some very small gaps around some of the pegs where they fix to the floor insulation. Would it be a good idea to tape the worst of these before liquid screed is poured next week?

Any pics

rampantbunny

BarneyMc wrote: »

Leaving shower areas a no-go areas. Will post photos soon though so you can see.

Hi Barney..my question was more directed at Bonzo Delaney...he was saying he did his shower areas also.

Bonzo Delaney

rampantbunny wrote: »

Are your UFH pipes run over and back across the joint between the shower tray area and the rest of the floor, or did you enter the shower area only once, loop around inside, and exit once?

If crisscrossing over and back and you later wanted to mechanically fix a shower door/screen to the floor you run the risk of piercing pipes unless accurate measurements were taken.

Interested in how you did this as I'll be getting UFH pipes down in week or two and plan on running UFH to shower areas also.

I ran them one line in , a loop then one line out in the access area, finished the bathroom loop then back to the manifold.
I wasn't to worried about drilling the floor as I put up a glass screen m


that was fixed to the wall and a rail across the top that was fixed to the opposite wall on the bottom , when I sealed it with clear mastic that held the bottom edge in place 9 years later still hasn't budged.

BarneyMc

hexosan wrote: »

Any pics

Will grab some later, thanks.

rampantbunny

Bonzo Delaney wrote: »

I ran them one line in , a loop then one line out in the access area, finished the bathroom loop then back to the manifold.
I wasn't to worried about drilling the floor as I put up a glass screen m


that was fixed to the wall and a rail across the top that was fixed to the opposite wall on the bottom , when I sealed it with clear mastic that held the bottom edge in place 9 years later still hasn't budged.

Very good. Thanks for that.

murphaph

Our UFH planner also included expansion joints in front of the hearth to allow for expansion due to the stove being on and the UFH off. Personally I think this is overkill but we will respect the joints when tiling nonetheless. The bloody tiles cost a small fortune so I don't want to see them crack and lift!

THE DON FANUCCI

anybody know what size room would warrant an expansion joint in the slab? UFH. dining room/kitchen is 8m x 4m. the perimeter insulation will surely help with expansion/contraction

murphaph

THE DON FANUCCI wrote: »

anybody know what size room would warrant an expansion joint in the slab? UFH. dining room/kitchen is 8m x 4m. the perimeter insulation will surely help with expansion/contraction

Is it a single heating zone? If you can regulate the temperature in the kitchen separately from the dining room then you should put an expansion joint in between the zones.

Water John

While it is one heating zone, it seems, it would have at least 2 loops.
That line between the 2 could be used as a break line/expansion joint.

murphaph

Yeah I found a document (in German only, sorry) which attempts to decipher the DIN 18 353 and DIN 18 560 standards (these are also available as EN standards if you can find them from the BSI somewhere) and spell out in layman's terms when and where to use expansion joints.

They say that if there are different zones (ie, each with their own thermostats) then there should definitely be expansion joint(s) included. They say if there are multiple loops, but all under the same heating zone and the flow temps will be the same in the loops, then you may leave the expansion joints out. In our house we have examples of both-our kitchen has 3 loops with no expansion joint between them. Our dining area/lounge is a continuation of the kitchen (all open plan) and that is a different heating zone (pointless if you ask me but anyway) so there is an expansion joint there. We have additional expansion joints simply because of the shape of the space (large L shape).

They also say that anything over an 8m side length would want to have an expansion joint fitted.

A simple rectangle 8 x 5 with the same flow temps and a single heating zone would be according to my reading that document safe enough to leave out the expansion joint.

If in any doubt, fit the expansion joint IMO. I reckon there must be loads of cracked screed installations knocking around but most are not tiled so the owners don't realise.

http://schubert-fussboeden.de/cms/images/stories/downloads/5_Fugen_bei_Estrichen.pdf

BarneyMc

Well that's the UFH installed and overall fairly happy. I've attached a few photos however showing some tears in the polythene. The clips were too long for the 25mm insulation upstairs and they had to be put in sideways. Also they were for a gun and not meant to be pushed in by hand - wonderful!

Anyway as always I'll be busy this weekend to fix up. I suppose a bit of tape around these areas would be the best solution? I was thinking of expanding foam/silicon/adhesive but it might not stick too well if walked over or the polythene moves?

The patch of insulation that lifted up with the tension in the pipes - I'll just stick it to the slab at the weekend and put a few bricks on so they'll be ok for the screed next week.

STRESS!

Water John

Thanks for the pics.
The black clips are 60mm I think and for a gun.
There are 50 and 40 mm red ones for hand push. That's no good to you, but the installer could use them on his next job. They are needed upstairs. The 40 is rare.

murphaph

I wouldn't fill those voids with anything. The screed will make its way into them and seal them up forever and the screed won't compress under foot like expanding foam or anything else you might put in there.

hexosan

BarneyMc wrote: »

Well that's the UFH installed and overall fairly happy. I've attached a few photos however showing some tears in the polythene. The clips were too long for the 25mm insulation upstairs and they had to be put in sideways. Also they were for a gun and not meant to be pushed in by hand - wonderful!

Anyway as always I'll be busy this weekend to fix up. I suppose a bit of tape around these areas would be the best solution? I was thinking of expanding foam/silicon/adhesive but it might not stick too well if walked over or the polythene moves?

The patch of insulation that lifted up with the tension in the pipes - I'll just stick it to the slab at the weekend and put a few bricks on so they'll be ok for the screed next week.

STRESS!

You've zero to worry about from them pics barney

BarneyMc

murphaph wrote: »

I wouldn't fill those voids with anything. The screed will make its way into them and seal them up forever and the screed won't compress under foot like expanding foam or anything else you might put in there.

But will the liquid screed not run in and get under the polythene, etc.?

hexosan

BarneyMc wrote: »

But will the liquid screed not run in and get under the polythene, etc.?

Not on a small punch hole like that. Your been the usual over anal self builder. We all have them moments.

BarneyMc

hexosan wrote: »

Not on a small punch hole like that. Your been the usual over anal self builder. We all have them moments.

Yes, I bet those installers thought the same about me heading back up the road to Derry!

Here's some 'self-build porn' for you Hex!

rampantbunny

BarneyMc wrote: »

Yes, I bet those installers thought the same about me heading back up the road to Derry!

Here's some 'self-build porn' for you Hex!

You mind me asking Barney, what the circular patch in the plaster is to the left of your window?

BarneyMc

rampantbunny wrote: »

BarneyMc wrote: »

Yes, I bet those installers thought the same about me heading back up the road to Derry!

Here's some 'self-build porn' for you Hex!

You mind me asking Barney, what the circular patch in the plaster is to the left of your window?

I think it's a sun spot and not on the actual wall. There seems to be a few along the wall/floor junction. Or it could be the last of my spirit leaving me!!