Post and beam

I am getting close to having to engage someone to install my UFH. There is a lot of discussion here about particular brands of manifolds/pumps flow valves etc. I (will) have 114 metres of ground floor in 2 zones only and am looking at 100-150mm spacing of pipes with a flow temp as low as makes good sense. What brand parts would i ideally specify and why please ?

Are these heliotherm units available in the u.k. They look interesting and not heard of them before. Edit: Found them

Achieving as good a Scop figure as possible is obviously a good goal. But.... I am moving from a small 3 bed semi built in 1986 of approximately 93 sq/m. And building a highly insulated 200 sq/m house. I doubt that even if i dont get the kind of Scop that i aim for that the new house will cost as much as the old one to keep warm. Lots of discussion focuses on x design factor being a little off will mean your new house will cost more to heat. True when comparing variations of the new build but probably not true when comparing, in my case, where i am moving from. Have i missed the point?

Thanks dude

Apologies, are we talking about the Riello or the Samsung now?

Thats good to know. At least they publish theirs. I could not find the figure for Samsung of similar size. The 'end of line' samsungs also look to be very good prices. And, as i have been informed on here before now 'Get a Samsung you wont go wrong'

I have been drawn to considering a Riello 6kw heat pump. Possibly 8kw. Looking at the documentation and remembering that modulation is important i see that they modulate to 40%. From what i have learnt here modulation to a 'low' value is considered important. So is 40% acceptable? What other factors might mitigate this. The units look to have a good Scop and price which was the reason for looking at them.

I am very grateful to be able to read all of the excellent content on this forum and have learned a lot. Still a lot more to learn of course. One of the things that confuses me is the cost comparison between the MCS route to ASHP installation versus the much cheaper cost of a traditional gas boiler. But, for a new build you also have to factor in the cost of a gas supply. In my case i am set on having a heat pump if i can get a reasonable quote. If a gas connection is anywhere close to what i have been quoted for an electrical supply @ > £6500 then the balance shifts, a lot. I dont recall this being part of the conversation for some reason.

Would you mind letting me know who in Hertfordshire you use. My planned build is in North Herts and i have failed so far to get quotes that are not stupidly high.

Thanks guys. That Vaillant diagram from @sharpener is exactly the one that i was given. It is a 7kw Vaillant that has been quoted for. As i am not keen on looking for a new location i think the best option is to find an R32 install

Possibly Really ? https://www.hireanrv.co.uk/rv-for-hire-uk-layouts

£1000/month. Around here that would not even get a 2 bed flat. I need 2 bedrooms.

Cheaper than renting a small house around here. Adventage of being on site of course. I went to see them and they said its an increasingly popular option for self builders. I thought some of them might be on here.

We were about to hire a 5TH wheel from CCRV in mildenhall to live in on site. I think i have misunderstood what ' designed for all year living' means. Specifically with respect to Laundry. These things dont appear to have a washing machine. So, how do you guys using this option do your laundry please?

A company that provided me a quote for ASHP has told me that the present proposed location as per my planning elevations and floor plans is not allowed. It is between 2 kitchen windows. Apart from noise to neightbours and clearance for airflow i did not realise there were such restrictions. I have looked through the building regs 2022 and cannot see what the issue is. Can anyone enlighten me please

There will not be brickwork at these points it would be way too expensive, and in the case of the large box dormer on the front possibly an issue of support. This is not the answer.

I thought it was a warm roof space but one of the TF engineers said something that made me wonder. So i have to say i dont know now I have this text from their build quote #Sloping ceiling(222mm rafter)U .12 via 2 x 80mm Kingspan K107 & 1 x 25mm Kingspan K107 kooltherm. # Cold roof ( cold space above e.g plane roofs & Eaves) U.11 2 x 200mm loft roll 40 ?

Are there any reasons why installing a horizontal cylinder is a bad idea. I am thinking 600mm centres posi joists and the loft hatch, more for a later replacement than the initial install. Also what about the weight, is there any practical difference between vertical on the first floor and horizontal in the loft. It appears that the spread of weight is better when horizontal actually. All advice gratefully recieved as always

My proposed house design is planned to have Cedral( £££ permitting) weathrboard on the gable ends and around the Dormers plus the down stairs dining room that sticks out the back. My TF supplier targeted a U value of .15 by using their Kingspan Ultima 15 but this was based on an all brick facade. I asked what was required to maintain this value with a lot more weatherboard than they anticipated. The answer is that the U value will just go out to .16 Not a lot of change you might say but going in the wrong direction. So.... For those that have employed weatherboard what would/did you do to maintain the U value you wanted? Perhaps extra thickness of external battens and 50mm of insulation

Thanks guys

Hi Guys I am trying to understand the received wisdom on the best way to get a double 3 pin outlet to the proposed kitchen island. should i get it laid under the screed when the UFH pipes go in? Thanks in advance as always

Oakbeamuk near cirencester

That is one of the things i have considered. If only because i expected to have to string the pipes myself. It appears the industry does not like to do it as its a lot of work. I do not yet have full structural data from the TF supplier so do not have SAP calcs but the target U values are .15 for walls, .12 for the floor (150mm kingspan under) and i think .12 or .11 for the roof. House will be 200 square metres with UFH at ground floor only. It was my belief that to avoid short cycling i needed close pipe centres, as low a flow temp as possible, 24 hours/day on and one single zone. The second sentence in my initial post at the top of the page throws this into doubt.

New thread as i have questions on the pipe centres point. Extracted from the Costs to install 8.5kw Mitsubishi R32 ASHP '100mm centres and minimal zoning (ideally open loop) will work best for maximum efficiency.' 'Once to get close 10W/m2 there is little difference. So much so that both have to run the heat pump at min flow temp for a heat pump anyway for both 100mm and 300mm centres. Which in its self can be problematic with a high mass UFH system as return temperature doesn't drop quickly enough.' For a few months while learning all i can about UFH via ASHP i have come to understand that close centres and as low a temperature as you can is the received wisdom. On that basis i have been planning on 100mm centres for my upcoming build with one global zone. Is this not a settled idea? It appears not.

and this reply.... And start a new thread to ask questions as i dont want to hijack this one.