UFH Layout

[Pete]

Hopefully just finished our UFH design. This is for a non certificated passive house. The house is a timber frame with passive slab using AFT .The house is on a North/South axis with South being at the right hand side of the drawing. I am hoping people could cast their eyes over this pipe layout. At the moment it has come out needing a 12 port manifold and the spacing is 200mm. 

My query is whether I have over done the amount of pipework and if this could be reduced. With the one room upstairs (not on the drawing but positioned directly above the Northern end of the house) I have not bothered with UFH but not sure whether to get a bigger manifold which starts to get expensive, just to put electric ufh to go with the bathroom and all of which may never be used if the house is as warm as we hope. All bathrooms will be electric UFH and any spacing you see, as in the long corridor, will be evenly spaced on the day of laying the pipes.

TIA 

[Barney12]

I'm not an expert on UFH but my one observation was:

 

Are the bedroom wardrobes fixed? If not is there not a risk that the layout might get reversed at some point which would cause a large cold spot? Or changed for a single bed? (These things might not happen in your ownership) My my understanding is only fixed furniture is piped around. 

Edited August 6, 2017 by Barney12

[Pete]

Yes they are fixed 

[PeterW]

There look far too many loops there ...

 

You've got at best 160sqm of floor which at 200mm spacing would be 800m of pipework. If I take out all your fixed bits then it's 120sqm, worst case then is 600m of pipe so you have an average of 50m of pipe per loop. 

 

Each bedroom can be a single loop - no issue there. Two loops to cover the big area on the left, one to cover ancillary areas should be 600m of pipe and the 6 port manifold. 

 

I'd take out all the beds/wardrobes etc as @Barney12 said and redo it. Rules are that it shouldn't go under kitchen cabinets, showers, baths or WCs. Anything else is fine. 

 

 

[PeterW]

Oh and as a passive spec house you can run the lot as a single system so no actuators required ... 

[PeterW]

Sorry I've just had a count up - that's a 6 port manifold not a 12 port...! 

 

Manifolds come as pairs - flow and return. A 12 port would have 12 loops and 24 pipe connections. 6 ports are pretty standard so should be change of £200 inc pumps and mixers. 

[vfrdave]

I'm no expert but will these layouts not bring an uneven heat distribution? Is it not recommended to run flow and return side by side as depicted in this Link 

[Pete]

Thanks for the response Peter. The ground floor is approx 230 sq m which I admit is not the easiest to get measurements from the diagram! All the fixed bits are fitted wardrobes, kitchen units/island unit and under the stairs etc. 

I appreciate what you are saying about the bedrooms which is how we approached it. The large area to the left is the lounge and kitchen/diner and the big room to the South is another lounge area which we are not sure is overkill. The windows are Internorm with a solar coating but we thought we may as well fit the pipes anyway and we can isolate if this room is subject to some sort of solar gain.

Thanks for spotting my test to see if anybody would notice the size of manifold I would need!!

[Pete]

Thanks for the responses. Did try to alter the pipe layout to the HPW link but Loopcad just threw in some layouts that would not work. Probably need to go back and try again. 

[PeterW]

1 hour ago, Pete said:

Thanks for the response Peter. The ground floor is approx 230 sq m which I admit is not the easiest to get measurements from the diagram! All the fixed bits are fitted wardrobes, kitchen units/island unit and under the stairs etc. 

I appreciate what you are saying about the bedrooms which is how we approached it. The large area to the left is the lounge and kitchen/diner and the big room to the South is another lounge area which we are not sure is overkill. The windows are Internorm with a solar coating but we thought we may as well fit the pipes anyway and we can isolate if this room is subject to some sort of solar gain.

Thanks for spotting my test to see if anybody would notice the size of manifold I would need!!

 

So if you run it as one big zone then having the solar gain on that slab may help you - you can use it to warm other areas as the pipework will even out the heat in the slab. 

 

LoopCad can be a bit of a mare - don't be limited by the 100m loop length either, Wunda do 120m coils as well. I've go some spare too if you have any short loops. 

[Pete]

Thanks for the offer of pipe Peter. I intend to run it as one big zone after changing the pipe layout to the better design. Did you get your manifold of Wunda also? I remember reading that people went for a manifold/thermostat that had a better incremental control as the house will be quite sensitive to temperature changes.  

[PeterW]

So if you can get to 5 loops then there is a smaller Esbe valve that you can get a replacement head for (I'm ordering these from Poland shortly) that gives you 21-55c as the current ones only go as low as 35c which may be too warm for a passive spec house. 

 

All mine came from Wunda Trade - I used the tray system as I've not got rebar in the slab as it's fibre reinforced traditional slab. 

[Pete]

Can you enlighten me as the reason to get to 5 loops pls? I assume it is because either the Esbe valve manifold is only 5 port or less or the replacement head only fits the smaller valve? 

f will be purchasing my pipe from Wunda so if the manifold is from a different supplier I need to make sure they are compatible.TIA

[Pete]

@PeterW  can you enlighten me as the reason to get to 5 loops pls? I assume it is because either the Esbe valve manifold is only 5 port or less or the replacement head only fits the smaller valve? 

I will be purchasing my pipe from Wunda so if the manifold is from a different supplier I need to make sure they are compatible.TIA

[PeterW]

2 hours ago, Pete said:

@PeterW  can you enlighten me as the reason to get to 5 loops pls? I assume it is because either the Esbe valve manifold is only 5 port or less or the replacement head only fits the smaller valve? 

I will be purchasing my pipe from Wunda so if the manifold is from a different supplier I need to make sure they are compatible.TIA

 

Correct - they do two valves, one larger one that the heads / valves aren't replaced as easily.