Mr Punter

Do a full plans submission. You would otherwise be at risk of the building inspector coming up with something unexpected late on when it will mean undoing a lot of work. I am getting an extension signed off for a friend where the builder went AWOL and the friend was left with no completion certificate. Luckily they had a full plans submission so when I met the building inspector and he made some extra requests and I was able to query them as they were not picked up on the plan check so we did not have to do them.

Greetings @DarrenA. @Visti is our man in Gravenhill. He was last spotted looking for a temporary staircase so I guess he has the structure up and roof on. Is that white brickwork with white mortar? I like the look. The design has some very expensive elements, but it does show. Can you go with a 150mm cavity? If so, you could use a full fill product like CavityTherm, with much cheaper wall ties. Using separate lintels for each leaf will cut down bridging and make the insulation boards fit more easily. I would need over double your budget to produce your house.

If you are on shrinkable clay, removal of trees that would have an impact on foundations is often something to do before you even apply for planning. Even small young trees are calculated at full maturity. Most of the warranty providers do a foundation depth calculator. Because your BCO has seen the trees before removal he may want deeper foundations and some Clayshield heave prevention on the inside face.

The main areas that need extract ventilation are kitchens, bathrooms and utilities. Although leaving a window open slightly is better than nothing, mechanical extract is far more effective at removing the moist air. The heat recovery bit is a nice-to-have but not essential IMO.

They are not as good to fix into or to plaster. I like to use 7 newton medium density aggregate blocks throughout, rendered and set. No confusion over different block types and fairly economical.

Yes. A few others do similar. Celotex suspended theirs, which was a shame as theirs had a better interlock to prevent water ingress. Be aware that some u-value claims include for insulated plasterboard and lightweight blocks, neither of which are my favourite.

Full fill rigid (PIR type) insulation will meet the u-values and work out cost effective. Correct installation is critical, so you need to make sure your bricklayers follows the instructions to the letter.

Be very wary of the proximity of trees with the clay soil. Even if they are small, Building Control will expect you to calculate and design the foundation on the basis of their fully grown height.

Leave it to the designer to decide but I would think timber should be simpler, cheaper and easier to connect on the truss press. You can specify the max floor deflection if you have concerns about bounce.

If you want good acoustic insulation the dense mineral wool is better, if you want thermal the PIR wins. You could stick some Celotex - say 30mm to the wall then a 10mm gap and 70mm metal stud with 2 layers of 15mm soundblock infilled with dense mineral wool. I am not sure if this applies:

You may be overthinking this. Independent stud wall (95mm timber or 70mm metal) with the face of the studs 110mm from existing wall with dense mineral wool infill and 2 layers of 15mm soundblock and there will be no thermal or sound issues. The regs give you lots of leaway as it is an existing wall and not exposed to outside. Metal stud would be my preference.

What is the wall makeup for the party wall? Is it 2 x single 100mm skins with a 50mm cavity, a 215mm solid wall or what? What BC are suggesting does not sound outlandish.

Was it building control who said this? You are right, the gaps underneath the infill blocks will give adequate ventilation, especially if you are detached with air bricks all round.

CT1 has its uses but it is very difficult to get an average finish and the clear and white look piss yellow after a while.

Pull the black collar towards the bit.

As above, get a professional to look at this. You may need to apply for consent to have a condition removed or varied and you can use the professional's advice to establish that the proposal will lessen the impact and is in line with policy / local plan. Do it now as it will probably take 3 months to get a decision.

I have used low iron glass in some 25mm thick external balustrading without handrail and the difference in colour is noticeable, especially when looked at from the edges. It lets all the light through, so make sure you have decent solar control. Does it work OK with low e coatings?

Fantastic job. I really like to see quality craftsmanship and it seems so rare.

+1

Really? We have several different glass specs on the same elevation - double glazed, triple glazed, toughened, laminated, different gap widths and pane thicknesses and I have not noticed any difference.

If you used stainless they will only have a bit of surface rust and should not cause any problems once rendered.

The glass in a frameless Juliet balcony should be toughened and laminated. It is likely to be at least 12mm thick. The glass thickness and the location of the fixing points are the main factors concerning how much flex. Are you having a handrail on the stairs? I wouldn't want my mum trying to grab the top of a sheet of glass to steady herself after one too many drinkies.

If the timber is left a natural colour, the bits you have coated will weather differently, so coat the whole elevation or it may look crap.

As long as they are the same colour and general style (modern, traditional etc) they will look fine.

I have known BC to object to any FR coating that requires periodic re-coating, which was why the non-com stuff was oft specified. A right pain and vast cost. As per @Ian this is only an issue if you are near a boundary (not necessarily another building) and if that is the case you may be better choosing a fibre cement based cladding.