smart51

How do you run a heat pump with both hot water and underfloor heating? For hot water you want to run at 60°C+ but for under floor heating you want half that for improved efficiency. Does the heat pump switch temperature when the thermostat signals heating demand or something?

Would they have had to reapply for planning permission once the old mill was knocked down? Would there have been a risk of them being refused? Or was it a case of once they'd started down a particular path, they were blind to any other direction?

Car sales for the last 12 months. 44% petrol, 36% hybrid, 15% electric, 5% diesel. Electric sales up 50% on last year. All non plug in car sales down. This is why all new builds should have car chargers.

I wondered if it was to do with not being able to set each room to a different temperature, but flow rate sounds about right. I'm planning passiv haus levels of insulation, and airtightness. My simple spreadsheet calculation suggests 130W heat loss for every °C difference in outside temperature, so maybe 4.5kW on an extremely cold night. On MHRV, I was up on the 2nd floor of our current house yesterday and could hear the missus running the shredder in the kitchen, but through the MHRV not up the stairs. I guess running separate pipes to each room and joining them by the heat exchanger would solve that, rather than running a single pipe and tapping off for each room.

My new build will have MHRV feeding all the house. It will also have a ground source (or air source, to be decided) heat pump. Most of what I've found online is a discussion of whether a heat pump should drive oversize radiators or under floor heating. Can the heatpump be coupled to the MHRV so that the warmed incoming air is heated a bit more by the heat pump? It would save a lot of piping and radiators. It seems a shame not to if the hot air ducting is already there. What are the reasons this is not more popular?

Prices from £2300 to £5300 depending on size. That's probably a 25 year payback. Something that would need a bit of thought before committing to. https://www.phstore.co.uk/awadukt-thermo

What kind of cost is a ground heat exchanger on a new build? (We're planning for about 200m2, possibly single storey if that is a big factor). It's not the sort of thing I've seen prices for online.

I'm considering passive cooling for my new build. Since we're digging foundations anyway, it is no hardship to dig a trench for an underground air pipe. And since we're having MHRV, all the incoming air comes through a pipe anyway, why not an underground pipe? In the UK, the temperature below ground is 12°C all year. Even if you only go a couple of metres down, it is 14°C in the summer and 10°C in winter. Winter air is pre heated by passing underground and summer air is pre cooled. If your incoming fresh air is, say, 17°C, do you need powered cooling in Britain?

We have MHRV in the space over the stairs to the loft conversion. The fans make the casing vibrate, which is transmitted to the loft bedroom. It is fine in the day (where I work from home) but it is noticeable at night when the house is quiet. It is our spare bedroom, so not a problem, but I'd advise keeping it away from bedrooms.

What is considered good practice for leaving a gap between the edge of a building and the plot boundary? Obviously if you build right up to the boundary you have no access for maintenance etc. Build plots in cities are often at the ends of existing gardens, so you're not next to your neighbour's houses or anything. Also, if planning says for example 2m between the boundary and the building, is that 2m to the wall or to any roof overhang and guttering?

Only if you assume people won't switch to electric until they are forced too. You seem to be assuming that the majority of cars sold in 2019 will be petrol or diesel. EV sales have been increasing exponentially for a decade. Last year they broke 1% of new sales, this year looks to top 2%. If things continue for the next 4 years as they have for the past 10, 2025 will have more EV sales than ICE.

In 9 years' time, all new cars will be electric. In 20 years, virtually all cars will be electric. In the life time of a new house, petrols and diesels will only be in museums. Why on earth would you build a house without a charging point. You will need one. Plus 7kW is plenty for a domestic charger. For a car in average use, you need 8 hours a week of charging time at 7kW. Plug it in overnight once a week and you're done.

Hello from Birmingham. This post was supposed to be introducing myself as the new buyer of a self build plot in Birmingham, but the lot was pulled from the auction over night due to a legal dispute over ownership. Anyway, hello from a soon to be self builder.