Mr Punter

We have used 90mm black MDPE for this. Comes on a coil and difficult to manage without special equipment but OK on a hot day. We joined the lengths with a compression fitting.

When I get samples I like to try to scratch them, smack them with a hammer and try snapping / bending and burning with a lighter. It doesn't indicate the effects of the weather, but it can give an indication of robustness. The corrugated stuff looks quite shiny. Will it dull down?

I have seen some fantastic houses in ICF, timber frame and brick and block. All are capable of achieving very high levels of comfort. There are pros and cons to each.

The same firm charged £3,740 per house for 2 houses 10 years ago, but they were a bit bigger. All were just mains fed - no tanks or pumps. I guess there is some economy of scale with multi units but maybe prices are coming down as it is more common for these to be specified.

We had 7 houses designed, supplied, fitted and commissioned and it worked out at £15 per sq m - £2,485 per house.

32mm for single phase

We had a contractor do some concreting and each batch was cube tested, with concrete and reinforcing specified by an engineer. I hope it doesn't fail as it was very expensive and now almost inaccessible.

Quite a few of the small tower cranes are 3 phase so you would be able to run one without a generator, but I am not keen on having a 415v site supply. Our domestic supply is 100A. Amazing how skinny the cable is though.

Getting 20 quotes is time wasting - for you and them. Between 3 and 5 is fine. Having good people you can trust is worth more than a cheap price and nightmare work / workers.

I have just looked at this from plan view. The idea below has a 2.1m wide circulation space extending from front to back with double height voids either end. The front door has been moved down to the same level as the kitchen. Stairs moved. Please note the arrows on the stairs always point UP. I haven't messed with the internal layout much.

The two sides of the house seem so disjointed that I would be tempted to split them into a pair of semis and either sell on or live in one half and rent the other.

General pottering around tasks are fine, but noisy power tools outside are a no-no. Inside works are OK but if you are using a multi tool for extended periods make sure the windows are closed (and wear ear protection).

https://www.diy-kitchens.com/products/appliances/all-sinks/lago-2-double-bowl-undermount-sink/in-lag340_340/wp2087324/#.XFBLidugKUk at £140 plus VAT.

Looking at the house, when you saw it, it probably represented good value. The reason for this is not only the lack of kerb appeal and the condition, but also the compromised internal space. If you are going to throw some money at this, consider your budget and what you want to achieve. I don't think that the front porch works alone will add much value over what may be gained with some inexpensive external decoration / landscaping / driveway works. The kitchen seems to be on the ground floor - about the same level as the external ground. I would expect to enter through the front door into a hall and have a door into the kitchen without going up / down stairs. I would also expect a WC on this level. Is this the case with your proposal?

There seems to be at least six rooms on the floor plan for what I assume is the living area floor(s). Is it bedrooms and bathrooms on the top floor(s)? Are the left and right hand offset vertically by about half a floor? I think that with a different stair / level arrangement, you could make much more of the space and link it together more coherently but it may be that it works fine as it is.

It is a question for your architect and engineer as the steel needs to support all that stonework and blocks and needs adequate bearing either end. You could use a separate steel for the inner leaf. Also I would ask them why you only have 50mm of wall insulation, especially as your wall is 450mm thick.

I am with @ProDave it looks like it was designed by Escher. The section on the left below has a monopitch roof that works OK as it is set a bit lower than the adjacent roof. Also, as @jack suggests, cladding above masonry = OK, not the other way round.

We paid £18,500 for 2 storey 480m2. We had cheaper quotes but they were too rough and we were town centre.

I am afraid that the Party Wall Act will come into play here. Although your sketch is neat it does not show the foundation and trench depths accurately. If the footings are 600 the trench should be over 3 times as deep as they are. Can you let us know why your drains are so deep? If they are already in place it may still be simpler to dig them out and re-lay them at a shallower depth.

Don't bother with UFC upstairs.

There often seems to be a few areas where you get loads of pipes. Is there no way of opening up the spacing adjacent to these areas?

I have not heard of this before. Did they put anything compressible around the edges? Also, is it the same against the lounge floor?

An architect I know is keen on the corner window and he achieves this with a fairly slim circular steel post on the inside which I imagine supports some steel beams above. I would expect the architect to understand how his design was going to work thermally, structurally, aesthetically etc and the engineer calculates loadings, steel sizes connections etc. and supplies you with a drawing and calcs for review.

Firstly, your invert of 1.6m seems rather deep. Are the drains on you side already laid? If not, see if they can be shallower, as I would normally expect them to start at about 0.6m, so the additional metre on yours suggests a very long run (60m?) Avoid the pump station as it is lots of additional cost and a nightmare when it fails as you will win the prize of a tank of raw sewage. Excavate the drain run at a fall of 1:60, picking up the in-laws drain on the way (this may be via a bottom outlet inspection chamber). If the main Anglian sewer is over 300mm dia you may be able to connect via a saddle connection on the top of the pipe.

You are looking rather fit in that picture Jeremy.