umiq88

Thanks for all the advice here. Slab is 75mm Cemfloor which is cement based screed. My thoughts were you need enough volume and surface area in the system to keep the heat pump temp down and avoid it cycling. I’d prefer not have a second pump as I’m trying to keep it to a minimum of components. @JohnMo I get your approach but do you see a downside other than the. Maybe pressure loss and materials to additional pipe work?

Thanks everyone for the replies. Yes seems to be a lazy generic design. House is new build and spec is following 206sqm U values are 0.15 - External Walls - 110mm cavity PIR and 50mm insulated plasterboard on external walls(37.5+12.5) 0.12 - Floor - 150mm PIR 75mm screed 0.13 – Roof – 400mm Rockwool or 200mm PIR 0.7 – Windows 1.4 – Doors I'm wiring myself so won't be putting in the stats but is there a downside to the closer pipe centres? Would turning down the flowrate have the same impact as larger spacing. I do want to make sure I have lowest flow temp possible in order to get max efficiency. Heat pump will be Daikin 8kW What questions would you ask or how would you go back to supplier to improve design.

Initial design has come back. Can anyone spot any issues?

In the process of wiring and getting UFH installed in a couple of weeks. Layout is 4 bed Bungalow and wondering about theromstats Plan is to have everything except the bedrooms on 1 zone and 1 thermostat per bedroom. The whole system should work off weather compensation but I want the option to have the bedrooms a little colder if need be or I have an older person in the family staying over. Where is the best location for the main thermostat controlling the whole house?

Like this. Only white pipe will be run internally and come out through external wall straight into boss pipe. It will have to go above the slab in the insulation layer. Below that and it would penetrate the radon.

Based in Ireland. Thanks Temp that's very helpful. This is bungalow so everything is ground floor. I've checked dimensions for toilet so ok with that. For 40/50mm pipes into gulley what height do you normally go through the wall at. Do you have a link to a gulley you normally use? My floor is made up of 75mm Screed, 150mm PIR, 100m Sub Floor Slab, 25mm Sand Blinding, 200mm Compacted Rock

No BC over here for self builds. I've attached a copy of the plans to give you and idea. Would you run one 110mm pipe into each bathroom and pipe the white wastes into that or should I have a 110mm coming up through the slab under each drain (sink, shower, bath etc) Wastewater treatment is located at the top right 10m away.

Looking for some help. Have foundations down and starting dead work. Will soon be laying soil and waste water pipes. Bath and Shower will be 50mm and sinks will be 40mm. Plan is to bring them individually down through slab and out through external wall into back inlet gulley trap. Is the height of the pipes critical. I have not done this before and wondering if the connection into the BIGT is adjustable or fixed height. Photos or a sketch would be fantastic.

Thanks after it bit of research looks to be a good unit. My only concern not knowing much about split units it - If gas is removed how easy is it for parts to become damaged from moisture. - I won't be installing for a year or so can these be stored properly dry or what would be the best way. Also any considerations for transport?

@Russell griffiths If the pipes start in the house, go up into the attic and then back down into the house then you create a pocket for air to gather. On a conventional gravity fed system this would air lock and you would either get no flow or reduced flow. I have not lived in or worked on many pressurised systems. Surely the same problem exists unless the pressure is enough to drive water through the system.

My cylinder and manifolds will be in the house. How do you deal with air in the pipes? Jenki makes a good point about air tightness which can be solved but is another consideration.

Originally looking at Grant (Chofu) 6kW unit but found a Hitachi at good price. Indoor Unit RWD-2.5RW1E-220S Outdoor Unit RAS-2.5WHVRP1

Thanks guys Location of UVC is a 800x1900 cupboard in the hall. Plan to make floor lower and put in floor drain. All CH and DW pipes etc will come from here and can be isolated and drained down. Looks like conduit in the floor solves all problems. Build is normal bungalow no upstairs. Attic vented to outside. Cabling will be chased into walls and go up to attic but will have to think about how to seal. Same for penetrations around lights.

New build looking to install mains water and UVC centrally and run piping through attic to kitchen, WCs etc. In my head sounds like a great idea for access, maintenance etc. however thinking about it am I going to need a air vents on every line or will a pressurised system push the air out?

Just an estimate when I got pricing. Haven't done calc yet. Anyone have any recommendations for easy to use calculator? Not sure on air tightness either. Will be going highest practical.