Upstairs UFH options

[richo106]

Hi All

 

I have spoken to a contractor who is going to install my slab/screed and UFH. I asked him to quote for ASHP upstairs with aluminium spread plates

 

He has come back and said that with 22 t&g flooring and carpet etc.. that it doesn't work very well at all

 

He recommended a low profile system that fits on top of the t&g flooring and then a thin 15mm screed over the top. He also said it would add a little more weight but nothing to worry about

 

I just wondered if any body has used this system upstairs?

 

We have discussed not having heating upstairs but we would like it just incase

 

Many Thanks

[JohnMo]

Really would not bother, UFH is a low temperature heating system and really needs to be on for lengthy periods and not really suitable for bedrooms where you want the room warm a short period before and after sleep, but not warm when in bed.

[LA3222]

Ignore the naysayers. I have it upstairs in a pug mix but this additional weight was accounted for in the joist design.

 

You'd be surprised how effective low temperature UFH is, folks like to say it doesn't work with carpet. That's is patently untrue, as I have a mix of carpet and tiled floor - it works.

 

I take the view that by including the floor area upstairs you are effectively doubling the emitting area so the amount of work each m2 has to do is significantly reduced. In cooling mode you are doubling the amount of heat that can be pulled out.

 

It will cost a couple of grand, when you are spending hundreds of thousands building this is chump change that is soon lost in the noise. 

[nod]

I wouldn’t bother with UFH for the first floor 

If your home is well insulated You will probably never use it 

We have UFH on the ground floor 

Small rads upstairs 

We have never used the upstairs heating in four years 

The temperature tends to track the ground floor temps 

[LA3222]

To put my first floor UFH use into context, my house U Values for walls, slab, and ceiling are around 0.11, windows triple glazed, MVHR and ACH of 0.2.

 

My house is well insulated. I do use the first floor UFH all the time when my heating is on. Our upstairs is around 21 degrees with downstairs around 22 degrees.

 

Moved into house December and UFH was turned off at end of Feb.

 

The UFH upstairs does work with carpets and is particularly useful in keeping all of the tiled bathroom floors feeling nice and warm.

 

Whether you go with it or not, its down to yourself. It annoys me when folks suggest there is no purpose to it.

 

Can you make do without? Of course.

 

If you fit it does it work and add tangible benefits - of course.

 

Ultimately it comes down to weighing pros and cons which is a subjective decision.

Edited June 14, 2022 by LA3222

[nod]

2 minutes ago, LA3222 said:

To put my first floor UFH use into context, my house U Values for walls, slab, and ceiling are around 0.11, windows triple glazed, MVHR and ACH of 0.2.

 

My house is well insulated. I do use the first floor UFH all the time when my heating is on. Our upstairs is around 21 degrees with downstairs around 22 degrees.

 

Moved into house December and UFH was turned off at end of Feb.

 

The UFH upstairs does work with carpets and is particularly useful in keeping all of the tiled bathroom floors feeling nice and warm.

 

Whether you go with it or not, its down to yourself. It annoys me when folks suggest there is no purpose to it.

 

Can you make do without? Of course.

 

If you fit it does it work and add tangible benefits - of course.

 

Ultimately it comes down to weighing pros and cons which is a subjective decision.

Tropical 🌴 

[richo106]

Thank you all for the comments, we have decided we are going to have UFH as LA mentioned that the cost in the grand scheme of things is OK and would rather not regret it.

 

I have looked into UFH a lot and familiar with the spreader plate and pug mix options but not the retrofit fit ‘egg box’ type with screed on a first floor. I didn’t know this was an option for upstairs…has anyone got any thoughts on this.

 

Thanks again 

[akjos]

On 14/06/2022 at 21:17, LA3222 said:

To put my first floor UFH use into context, my house U Values for walls, slab, and ceiling are around 0.11, windows triple glazed, MVHR and ACH of 0.2.

 

My house is well insulated. I do use the first floor UFH all the time when my heating is on. Our upstairs is around 21 degrees with downstairs around 22 degrees.

 

Moved into house December and UFH was turned off at end of Feb.

 

The UFH upstairs does work with carpets and is particularly useful in keeping all of the tiled bathroom floors feeling nice and warm.

 

Whether you go with it or not, its down to yourself. It annoys me when folks suggest there is no purpose to it.

 

Can you make do without? Of course.

 

If you fit it does it work and add tangible benefits - of course.

 

Ultimately it comes down to weighing pros and cons which is a subjective decision.

 

@LA3222 how did you go about calculating W/m2 for the UFH for both ground and first floor (if going from a known total amount of fabric heat loss)? You obvs have a very tight house with minimal losses, but did you just divide the total heat loss by the total floor area (ground + first floor)?

 

My estimated heat loss on slab and ceiling will be roughly the same, so both floors balance out, but my confusion comes from the fact that not the whole floor area has losses both up and down. I'm trying to figure this out now in order to calculate the spacing/flow rates so that I can run an ASHP most efficiently 24/7 without any buffers.

Thanks!

[Adsibob]

We have UFH on all three floors of house. Our build up on first floor is as follows:

 

18mm engineered oak floor

25mm cellecta XFLO boards (this is FF range, i.e. foil faced https://www.cellecta.co.uk/product/xflo-ff/ they do a similar range without the foil for bathrooms). We went with 25mm boards to accommodate 16mm diameter pipes. Smaller pipes will work with thinner boards.

22mm egger chipboard flooring

joists.

 

This worked out as quite a thick build up, but the system is really good. Much more responsive than I expected. Takes about an hour to boost the temp by the first degree, than another 40 minutes for second degree, and then another 30 minutes or so for third degree. Depends on how cold your room is to start though.

 

Also very solid underfoot. We speced the extra dense XFLO boards for the area of the bathroom where we have the swimming pool enormous bath.

[LA3222]

On 07/11/2022 at 16:19, akjos said:

 

@LA3222 how did you go about calculating W/m2 for the UFH for both ground and first floor (if going from a known total amount of fabric heat loss)? You obvs have a very tight house with minimal losses, but did you just divide the total heat loss by the total floor area (ground + first floor)?

 

My estimated heat loss on slab and ceiling will be roughly the same, so both floors balance out, but my confusion comes from the fact that not the whole floor area has losses both up and down. I'm trying to figure this out now in order to calculate the spacing/flow rates so that I can run an ASHP most efficiently 24/7 without any buffers.

Thanks!

I let WUNDA do the design and then I just installed it to how they drew it - easy enough.