Mr Punter

I am a bit late to this post but it may be worth claiming from the warranty provider for the cost of installing insulation and airtightness to meet with building regs. It is a defect. I have gas CH and rads in an averagely leaky (4.25 m³ / (h.m²) @ 50 Pa) 190m2 terrace house and during the worst cold snap the gas heating cost was £6.50 per day. Thermostats are between 16 and 20 depending on day / night and the temperature is easily maintained. 2 work from home + 2 students.

You need a structural engineer. They will give you all the calcs and the spec to satisfy Building Control and they will have PI cover to satisfy the warranty provider too. 150mm is quite slim so they may suggest some steel.

Slate is pretty good. For 40mm you may need 2 layers but probably 1 will work.

I was pretty sure it would be fine, but that link to the Grand Designs episode made me think twice. I bet you asked santa for fresh underwear!

Was this OK in the end @Moonshine?

It is an S & P inline fan mounted in the plant room above the kitchen. There is a draught flap on the outside vent. You could not mount this one open to the elements.

Normal render with 2 coats of white masonry paint stays white a lot longer than the through coloured / monocouche stuff, as well as being less prone to algae and mould.

You could try Bushboard Nuance panels, which are waterproof. https://www.bushboard.co.uk/nuance

No approvals needed unless there are any "Before occupation" planning conditions.

It has been exceptionally cold for a few weeks and it seems that heat pumps do not do well with this. I imagine the efficiency drops a great deal as there have been loads of posts over the last couple of weeks from heat pump owners crying about their energy costs. I suspect that it will ease up soon and the running costs will drop a good deal. Did you have an airtightness test? That seems to be a decent way of working out if you are leaking lots of air but you need the doors and windows properly sealed first.

On one side the structural opening is much higher than the door lining. Ideally I like the door lining to be the width of the wall reveal. I guess this was the knock through for an extension? The skirting architrave looks, as I believe they may say in Southend, pony.

Nail a bit of mesh for the time being to keep out vermin.

Doesn't the HW tank have an immersion heater as a backup? For heating you could get some cheap electric heaters.

If the flooring is stuck down the glue is less than 2mm. Do you need any allowance for door mats?

We voluntarily fitted charge points in a terrace of 7 new houses. We used the bollard type 1 per house, each with 2 sockets. When we were fitting them some passers by commented that planning must have made us fit them. I just thought it made sense to fit them at the outset so that if a householder wants an EV there is no issue with installing and siting a charge point. So far only 2 get regular use. They are not spyware enabled, just Rolec Basiccharge pedestals.

Given the title I am surprised that @pocster did not gravitate to this thread.

If you have gone for posi joists for MVHR ducting, make sure the ducting goes in with the joists and you don't get stuffed up by strongbacks or end walls, especially if you are using rigid duct.

+1 to foam

You will end up with a bulkhead in the kitchen as the stairs will only have risen 1600-1800mm when it clashes with the kitchen wall, so any tall units or wall units in that corner will need to be "modified". Unrelated rant: I hate it when arrows on stair drawings do not indicate up. Just so confusing. It is sometimes even worse when they put "up" and "dn" next to the arrow as they look the same with the plan the other way up.

Looks like Artex. If it is left it is harmless. If you are going to remove it or sand it down, get a bit tested.

Could just be some soggy materials left in a dumpy bag?

The pipes are really strong. Unless the temperature indoors got really low I don't think it could be leaking pipework. Can you see if they are frozen at the manifold?

I am surprised they visited. Normally only after an accident or grass up. If it is only you and Mrs @nod skidding about it has nothing to do with HSE.

Can you drop the level of the paving adjacent to the doors so it is 150 below DPC?

The plot does not look big enough to accommodate this. Is there anything similar around?