ProDave

Do you see water flowing properly on the flow meters on the manifold?

Wet UFH upstairs can be done easily. If he is quoting £10K for upstairs UFH how does that compare to the downstairs cost? Many of us find in in a well insulated modern house you don't actually need any heating upstairs, or in any event a lot less heating than you need downstairs, so radiators might be fine even if not over sized if you don;t need much heat.

The new Scottish law that comes into effect next year are NOT building regulations. It is something dreamed up at Holyrood and apples to all houses, so most will be retro fit. Building regulations still apply to new builds and they are different, as are the smoke alarm requirements for rental properties.

Heaters over 2kW are generally expected to be on their own circuit so your water heater and induction hob are almost certainly already on their own circuit. Diversity takes care of the likelihood of everything running at the same time.

Madness. Wireless ones are generally £50 more than a fixed hard wired alarm. The bit of cable to connect them is WAY less than £50 and easy to fit in a new build (which is what yours is in effect) The only place for wireless is a retro fit where the amount of disruption to the building to hard wire it is too much.

What does your installer say?

If it's not delivered yet, change that OSB order for 2400 by 1200 metric. I really don't know why they still make it imperial size, but if you use that and set your stud spacing for that, it will not match the plasterboard, alternatively you will be cursing at trimming every sheet down to 1200 to make it work. And are you really paying £30 per sheet? Christ on a bike.

That will go into the top part of a telescopic P trap. But sink and a half usually have a more versatile single trap with a tee connection to take both wastes into one trap and both halves are usually telescopic. So buy a 1 1/2 inch telescopic P trap and swap the parts over, use that one with the fixed nut for your belfast sink, and the one that comes off the telescopic trap should go in the kitchen sink to replace the one you have borrowed. Sometimes it can be handy to have a box full of assorted drain fittings to do a bit of mixing and matching.

That lot adds up to a total of 4140W or 18 amps. At that power rating you could just put a 13A plug on each one and just plug it into a socket if they are in the right place?

You have permission for the dropped kerb. Say no more, and just get a contractor with a minor street works permit to make the dropped kerb for you.

My issue with the ones with non replacable lamps, is what happens in 5 years when one fails and identical replacements are not available? If you do go that route, buy plenty of spare fittings.

Or you can buy wireless relay modules. I use one for my portable convector heater dump load. Transmitter in the box with my Arduino and receiver in a 2G back box creating a wireless switched 2G socket.

The only LED failures I have had was several Philips LED Bayonet lights bulbs. considering they were a make I used to respect and were not cheap, very disappointing. I do NOT like the current trend to downlighters having non replacable lamps, and glad all of ours are GU10 fire rated fittings with LED lamps.

I actually find the Honeywell ones quite reliable. Agree the Drayton ones are pants. If you think 2 port valves are bad, you have obviously never had a system with a 3 port mid position valve.

Another sealant I use is Water Hawk Potable water jointing compound

I just love the low energy of an all LED lit house. LEss than 150W with every single light in the house on. I can remember when just a kitchen easily used twice that amount. Nothing fancy here, downlights in hall, utility kitchen and bathrooms, fancy light fittings in living room and dining room, and standard pendants and shades in bedrooms. Warm roof here so ceiling penetrations for downlights not an issue (I might have mentioned a warm roof was one of or best design choices) and with the advent of LED's my aversion to downlights has gone.

Has anyone done a heat loss calculation on your house yet? Ours needs just a little over 2kW when it's -10 outside and +20 inside. Based on last weeks heat pump consumption we are running at about 1kW heat input at the moment (averaged over the whole day, that does not mean it is on 24/7)

The ONLY thing these fancy internet connected thermostats offer is the ability to change the settings or turn it on and off from a remote location. e,g, if you go away for 2 weeks in winter, then a day or 2 before your return you can turn the heating back on. If you don't want that function then indeed they are a waste of money. To be honest it costs so little to heat our house, I would just leave it on while away.

A caravan as a dwelling WILL still need planning permission. It is building regs that it avoids. So I would say you would be okay just placing a few pads to spread the load, the more the better.

Our house has 8 along an 11M wall, so either mine is over ventilated, or yours will be under ventilated.

Dot and dab plasterboard as @nod has said can be done properly. But all too often the plasterboard is just fixed on blobs of glue with no detail thought about. the result is the top and bottom of the gap behind the plasterboard is often left open to the cold loft space, cold inter floor area and even sometimes cold under floor area if a downstairs suspended floor. This creates what has become known on here as a "plasterboard tent" where cold air can circulate behind the plasterboard and negate any insulation in the walls. It is so frustrating to see this time and time again as it appears the vast majority of builders don't know or understand the problem and the relatively simple way of avoiding it is to ensure a continuous seal of adhesive along the edges of a board. It sounds like yours was build by a typical didn't care or didn't know type builder.

Is this house "plastered on the hard" or dry lines with plasterboard?

It could well be the thermal mixer cartridge has failed. If you live alone so nobody else uses a tap while you are in the shower you might not notice it has failed and is just working as a manual mixer valve.

By 2008 building regs required a cavity to be ventilated. Unfortunately most builders have no idea about air tightness and you will have lots of leaks between the cavity and the inside of the house, most likely joist ends, poorly pointed blockwork that won't even have been plastered in the inter floor area etc. Sadly no easy fix. It's what I say about most of the UK housing stock is built to really poor standards, even some quite recently built houses. It's the sort of detail that is easy to get right when building, if you know what to do and can be bothered.

Yep I had a customer like that, running a washing machine AND a tumble dryer from a wound up extension lead. I think she said she was on the third one "they keep melting" before she called me to fit a new permanent socket to plug them into. The extension lead in the picture in this thread does appear to be fully unwound. My own "3kW" immersion heater appears to draw more like 2.8kW in real life.