running pipes on kingspan floor insulation

[yar1950]

I am in the middle of laying the 70 mm kingspan insulation board on the floor of mty new build.
The plumber told me that his plasic heating/water pipes go under the insulation. The Kingspan instructions say the board must be tight together, there are so many pipes going in all directions I can't cut the kingspan arround them.
I am beginning to think that the plumber is wrong and the pipes should go in the 75mm screed. It would certainly be easier and neater.
Can anyone advise please?

 

[noseall]

your plumber is being lazy, as he probably does not want to tape the pipes.

that said, he does have a point. the heating and cooling of the pipes will inevitably lead to cracking of the screed.

 

[yar1950]

Hi Noseall, thanks for getting back to me. Someone else did tell me that there is a special trunking that goes into the screed to house the pipes, would that still crack the screed?
My main worry is that after laying the kingspan in a couple of rooms I found that I had to leave large gaps where it buts the pipes, it seems inpossible to cut voids in the kingspan so that it covers the whole room.
Kingspans fact sheets say that the kingspan should have no gaps so leaving large openings where the pipe are is completely defeating the object of insulating in the first place. Kingspan also advises putting it on sand so that it does not rock on the concrete, if again they are that particular it is impossible to stop rocking if trying to go over the pipes.
I have had to put the screeders off while I get some definate answeres as I really think to do a decent job it is going to be better to have his pipes up and put the kingspan down to spec and then have the plumber tape/ trunk the pipes after.
If you have anymore thought after reading this , they will be greatly appreciated.

 

[noseall]

we always fit our insulation below the main floor slab where applicable, i.e. building from scratch. this means any floor mounted pipe runs must go into the screed and be taped or sleeved.

why did you decide to sandwich yours between main slab and screed?

unfortunately, i have not heard of a one piece covering that can successfully overcome the thermal effects of heating pipes.

 

[yar1950]

Thanks again noseall, I forgot to mention the floor is block and beam. As you say, you put the pipes in a sleeve in the screed I think I will have to pay the plumber to redo them in the screed with the tape.

Regards
RAy

 

[shane123]

I, ve worked with the screeders hard work, they also do a lot of screed with the under floor heating.
For large building contractors so spec is important I suppose
The poly membrane first then king span boards,
Then normally the pipes are sleeved with the plastic casing then special clips hold this to the top of the king span boards,
Remember to stagger the boards when laying helps lock everything in place,

hope this helps just make sure its how you want it, as the screeders are animals and are paid to screed.

 

[JohnD]

I think he has probably finished it by now

 

[^woody^]

I think he has probably finished it by now

LOL - you never know - I've still got jobs from 2001 unfinishd, and my conservatory floor, dug out in late 2006 wont be screeded untill later this year if I'm lucky