ProDave

Isn't that in effect a cut roof pre fabricated and lifted in in sections?

When I saw the title of those two pictures, I had to scroll down oh so carefully in fear of what I might see.

Even paying a standing charge would probably be cheaper than paying to disconnect and re connect.

All I can say is all houses I see being built up here have sarking on the roof.

I made mine 2.5M wide. More of an issue was getting the height I required, I wanted it tall enough to get the Landrover in. That height requirement ruled out sectional doors. I ended up with a rolller door. they have the big advantage of fitting to the inside face of the opening, so when open, there is no reduction in the actual opening, These don't come in standard sizes, they are made to measure. Cost £500 from ebay.

Can you not build one, live in it for a few years, claim all the exemptions and VAT reclaim, then sell that and build No 2. CIS registration is straightforward at least as a subcontractor, I have to be registered for that as a sole trader for the times when I work on a new build and get tax deducted by the main contractor.

Or cut out a socket box and fit an additional socket All depends where the hole is.

Gyproc Joint filler. Unfortunately you only seem able to buy it in large tubs. It takes ages to dry if you put it on too thick, so think several small layers with time to dry. When dry it sands beautifully to get a nice finish. Must be sanded dry with a very fine paper. Take a sharp stanley knife and go round the hole to cut the paper and taper the hole inwards (think countersinking it) so you don't have flappy paper edges to worry about, I have a large tub at present. If you bring a suitable air tight vessel you are welcome to a few scoops of that when I see you shortly.

The floor is tanked (wet room) and the tanking goes a little way up the wall. The floor was then tiled. Then the wall board applied. Clear sealant (I used stixall) to seal the bottom edge, wiped clean so it does not protrude, then when that has dried a bead of white sealant as a decorative finish. I used the plain boards that have a vertical joint, as it happens there is only one such joint. Theu also do a version where the panels interlock to the next one making an invisible joint. About £100 per sheet from Jewsons They do sell an edge bead to seal the bottom joint but aparently it is very poor and leaves the bottom of the panel sitting in a channel of water. Avoid using that.

Not in Scotland, a sarking board is a (sensible) building regs requirement.

I will comment on the tiles. Don;t. Use a waterproof wall board such as Multipanel instead. No joints, no grout, totally waterproof.

How important is it to have "nothing" at the eaves? Would a minimal overhang do? This is what I have done: The eaves board is just regularised construction timber, fitted before the render. Eventually it is going to be over clad in aluminium painted to match the window colour.

Can you give us any other information about the building? How was it built? masonry or timber frame? did you see it during construction? do you have any photographs? Architects drawings? etc etc.

If you want an idea of the running costs you can achieve with a bit of care, here is ours so far. Walls etc barely to passive house insulation levels (typical U value 0.14) triple glazed, mvhr, ASHP driving UFH downstairs only. Bear in mind also we are in the highlands. These last 2 very cold weeks, we have been using 95KWh for heating, and 35KWh for hot water per week.

My solution is natural. Lots of trees south of the house. In the winter without leaves, they let most of the sun through. In the summer in leaf, they screen the sun nicely.

I think our house is probably a good ballance. Definitely not zero heating, but very low heating required. But it's also a very comfortable house, no sudden changes in temperature, no draughts, and good air quality thanks to the mvhr. I think it has been mentioned before, but when we finally reach state pension age, if they are still paying the winter heating supliment, that will probably poy for most of our annual heating bill. Now if only I could find a way to reduce the council tax by a similar amount to my now low fuel bills.

Most of our walls etc have a U value of 0.14, and the calculated heat loss when it's +20 inside and -10 outside, is just a shade over 2KW, which is comfortably delivered by a 5KW ASHP

I must have a mental block, or a browser compatability issue. I have completed the survey but can't find a "done" or "submit" button??????

The manual for the Upnor system is here https://www.uponor.gr/-/media/country-specific/uponor_com/download-centre/indoor_climate/underfloor-heating/brochures/mi-control-system-controller.pdf?v=00980da3-16c5-40ed-ac3d-a8bebbf3c6af That thermostat has provision for a floor temperature sensor that you don't appear to have so the floor setting will do nothing.

Why bother with masonry? Make it timber framed with some form of cladding then almost all the wall thickness can be insulation.

I considered ground source. The pipe that you bury and the antifreeze to go in it exceeds the cost of the heat pump. The other consideration is noise. the GSHP unit will be in the building purring away. I chose a monoblock ASHP instead, it is pretty quiet, but the main point is the noise is in the unit outside, not in your building.

Taping and filling plasterboard is a DIY job. If it needs to be a fireproof ceiling to a habitable space it needs to be 2 layers of the 15mm pink board with staggered joints.

Can you not at least get hold of the design SAP document?

Is there a manufacturers name and model number on that thermostat? Googling DT-37 etc does not help much.

Another here standing up in defence of the WBS. Like @joe90 I have a 4.5KW WBS that takes it's combustion air from outside via a duct, and by using an insulated sleeve around the flue pipe did a pretty reasonable job of sealing where that exits the building, I can't say I have noticed it being a noticable source of heat loss from the house when not in use since I installed it. For me, the No 1 reason for having the WBS is firewood is plentiful and free here. The thought of spending £30 for 6 hours fuel would put me off ever using it. That would be way more expensive than the main heating (which seems to be averaging £2 per day for the whole house so far) in fact that 6 hour burn would cost more than a weeks whole house heating for me, The equation may change if you have to buy your firewood. If you really don't want to burn wood, I would get an LCD screen "stove" instead Overheating has to be thought about. Our house basically has 2 large rooms downstairs either side of the stairwell each with double doors to the stairwell. Doors open it is pretty much one big space and heat can convect up the stairwell. Open up like this the kitchen / diner where the stove is, gets to about 25 degrees and the rest of the house warms up as well. Yes I am sure if you light the stove for too long with that room shut it probably would get far too hot. Finally I will add that we are very pleased with the stove we ended up with, a Mendip stoves Churchill convection model. It has the ability to run at a lower power while still maintaining a good flue temperature, and is the first stove I have owned where I can genuinely say it keeps the glass clean.