UFH layout in odd-shaped space, on overlay panels

[andyscotland]

My extension has finally reached the point of laying the UFH and flooring. I'm using the pre-routed overlay panels, so am tied to 120mm pipe spacings and ideally as many as possible of the pipes running in the pre-cut grooves / round the pre-cut bends.

 

I wasn't completely happy with the layout my supplier did. They don't manage to get to several of the perimeter walls until quite far into the loops, and they've bunched several flow & return pipes very close together along the edge of a corridor which in my head means the return will have taken quite a bit of the heat out of the flow before it ever gets into the rest of the space. I can't avoid them running near each other, but I think I can at least space them out a little bit.

 

So I've been trying to draw alternatives with LoopCAD, and I'm not sure which is best - or if there's a better option...

 

I've shared 3 options below, as both the schematic and LoopCAD's model of the circuit temperature along the length. 

 

NB:

• The ensuite will have electric UFH within the tiling, so doesn't need to be part of the wet system.
• The manifold location is locked in and can't change.
• I haven't fully modelled the space in LoopCAD, so ignore the flow & DeltaT figures on the circuit labels.
• In case it's not obvious, there's a door between the utility & bedroom, but no door where the corridor (past the en-suite) opens out to the rest of the bedroom.

 

Option 1:

Closest to what the supplier did, but with some tweaks to take the flow pipes round the walls first. Probably the easiest to install. I'm a little nervous that the floor will feel unevenly hot as you walk the length of the room (e.g. if you get out of the far side of the bed and walk to the ensuite).

 

 

 

Option 2:

Less "stripey" heat than option 1, and more of it near the window & far wall where heat loss will be higher. Downside is that there's possibly an even more noticeable change in floor feel as you go from the bedroom to the ensuite corridor.

 

And most of the blue circuit is below the area where the beds will be. It's also a lot more faffy to install.

 

 

 

Option 3

 

I think I like this the best. It gets most of the hottest water into the open floor area, with the area under the beds on the return half of the pipe. I think that should give quite an even temperature / gradient across the area of the bedroom & corridor where people will be walking. It will still be more of a faff to install than the simpler option 1 - though I'll hopefully be able to get the spacings about right to mostly use the bends & link channels that are already formed into the boards, but I think potentially worth it?

 

 

Would love to hear your criticisms / advice!

 

 

 

[JohnMo]

2 hours ago, andyscotland said:

haven't fully modelled the space in LoopCAD, so ignore the flow & DeltaT figures on the circuit labels.

I would do that extra step, make system balance out the box.

 

1st image just delete the red loop use the blue and green loops to heat those areas as well. Each loop is only 60-70m long so you have plenty of scope for this. 

 

Then in bedroom do whichever is easiest to install.

 

You certainly do not need much heat in a utility room.

[andyscotland]

Thanks @JohnMo

 

20 hours ago, JohnMo said:

I would do that extra step, make system balance out the box.

 

Ah yes I was planning to once I settle on a layout - bit of a LoopCad learning curve and the walls etc are not in its standard constructions so was going to come back to that.

 

20 hours ago, JohnMo said:

1st image just delete the red loop use the blue and green loops to heat those areas as well. Each loop is only 60-70m long so you have plenty of scope for this. 

 

Unfortunately I already have the kit and the pipes are supplied as three 80m lengths so I don't think I can delete the red loop entirely. But I could maybe use it just for the utility and cover more/all of the bedroom corridor from the blue & green loops.

 

20 hours ago, JohnMo said:

Then in bedroom do whichever is easiest to install.

 

You certainly do not need much heat in a utility room.

 

Agreed - although it also serves as a hallway between the house & bedroom, and between outside & bedroom, so it maybe needs to be a little warmer than a true utility room.

[andyscotland]

OK I have come up with another layout that (just) stays within the 80m length constraint I have, but separates the loops for the bedroom & utility so they can be balanced more easily.

 

It does mean a bit less heat in the utility room corridor, but that's maybe not a bad thing, and it allows me to get the flow & return pipes much further apart. Any thoughts welcome!

 

 

[JohnMo]

Seems a lot of work your doing to get around an early purchase.

 

You really should add wall, floor and roof u values to loopcad. You may find 240mm pipe spacing are fine for hall and utility. Then you get down to 2 loops. Your dT of 11 really needs to be between 3 and 5. Not sure how you control flow rates down to 0.3L/min.