Underfloor Heating

Doozergirl

Rosa_Damascena said:

grumbler said:

mug2007 said:

The builders broke up and removed the existing floors then other prep work such as insulation, concrete, membrane as specified in drawings.  Then the screed company sorted a ufh design with the layout of pipes (not under kitchen units) and location of manifold. We agreed heating zones and purchased thermostats for each. Then all in one day they covered floor with black dpm, pipes down and then liquid screed piped in.   Lots of videos on you tube.  Quite impressive and quick.

What sort of "existing floors"?

What about the insulation?

And drying time?

How big is your manifold btw? Where have you sited it?

Drying time is about a month per inch, for suitability for LVT, otherwise you install a liquid DPM over it to add to cost. 

Your manifold should go as close to the centre of the house as you can get it as it helps with zoning and making routes easier.  

mug2007

I think we had concrete floor in our kitchen which was quite a workout for our demolition team to remove and we had floorboards in our other rooms.  The insulation underneath was a few inches thick and rigid.  The manifold was located under the stairs, a central position, it has a custom cupboard around it, depth is probably 12cm, height and width about 75cm and that has covered the manifold and the other stuff (can't remember what).  If it fails the hygrometer/humidity test, Karndean require less than 75% then we can pay a few hundred more for the DPM to be put down but we are going to give it a couple of months in the hope it'll dry out.

Eldi_Dos

Would some domestic fans help with air movement and the drying out process.

Rosa_Damascena

Doozergirl said:

Rosa_Damascena said:

grumbler said:

mug2007 said:

The builders broke up and removed the existing floors then other prep work such as insulation, concrete, membrane as specified in drawings.  Then the screed company sorted a ufh design with the layout of pipes (not under kitchen units) and location of manifold. We agreed heating zones and purchased thermostats for each. Then all in one day they covered floor with black dpm, pipes down and then liquid screed piped in.   Lots of videos on you tube.  Quite impressive and quick.

What sort of "existing floors"?

What about the insulation?

And drying time?

How big is your manifold btw? Where have you sited it?

Drying time is about a month per inch, for suitability for LVT, otherwise you install a liquid DPM over it to add to cost. 

Your manifold should go as close to the centre of the house as you can get it as it helps with zoning and making routes easier.  

I understand this to be the case, but that in modern times an accelerant can used to reduce the drying time?

carpetseller

A liquid screed would also improve thermal conductivity .

mug2007

Eldi_Dos said:

Would some domestic fans help with air movement and the drying out process.

Yes thank you.  The screed company have advised opening the doors and windows and running the heat through the underfloor heating to help dry.  We have agreed to this dpm if the hygrometer fails for the third time given it would had the full drying time by then.  

J_Smotthies2021

It seems, we will do electric underfloor heating with tiles. What sort of tiles are good?

Doozergirl

Any kind of ceramic or porcelain tile is fine, but I hope it's a small room because electric UFH is incredibly expensive to run. You would never want to run it as a main heat source.  

Edit: I suspect the adhesive is more important to be compatible with temperature fluctuations than the tile itself.  

travis-powers

Doozergirl said:

Any kind of ceramic or porcelain tile is fine, but I hope it's a small room because electric UFH is incredibly expensive to run. You would never want to run it as a main heat source.  

Really didn’t want to read that, Im going to be knocking a couple of walls out to give us a bigger kitchen and that was going to be my primary heat source!

Doozergirl

travis-powers said:

Doozergirl said:

Any kind of ceramic or porcelain tile is fine, but I hope it's a small room because electric UFH is incredibly expensive to run. You would never want to run it as a main heat source.  

Really didn’t want to read that, Im going to be knocking a couple of walls out to give us a bigger kitchen and that was going to be my primary heat source!

I wouldn't.  I didn't.  We've built this house and it's incredibly airtight and insulated.  I did all the maths to try and work out potential bills with various heat sources. 

On our current tariff, electricity is 6x more expensive than gas.  Electricity might be 100% efficient compared to 90% for a new shiny gas boiler, but that doesn't even go part of the way to covering the gap in cost.
Electric heating people love to sell it being more efficient, but that isn't a cost saving! 
 

We had a post in here a while back where the OP couldn't figure out why their electric bill had gone through the roof.    Turned out to be the new UFH in their utility, of all places.  

It's fine to warm your feet of a morning for a little while in the bathroom, but that's all I'd use it for (but we're still not!).