Mr Punter

The internal expanding foam is to help airtightness and insulation between the frame and the structure. The outside seal (Compriband tape or mastic seal) is mostly the bit that makes it weathertight.

Extract is the way if you are into cooking. Fried onion and garlic, sizzling steaks, bacon, stir fry, curry, fish.

What about a scaffold hoist and some web slings?

You can run surface water into surface water drains and foul water into foul water sewers. What are you draining from the extension?

I think that part M will not apply as this is change of use.

Ok I understand. I normally like to have paving sloped away from the building.

Cemfloor should be fairly flat. I have just had one poured and apart from a few surface imperfections, which will scrape off easily, it is very flat, so you could not slide a piece of paper anywhere under a 6' level.

Good move. We have a small 4 bed student HMO. Parental guarantor for each. Agent does all the admin. They also do all inclusive of bills.

If this was included in the purchase agreement they are obliged to provide them or risk being in breach of contract. Get your solicitor to request them.

You should ask the seller for this.

We use a managing agent. Well worth the money. Shop around. We get full management at 5%. Also have a guarantor for each tenant.

131mm but make sure there are no strong backs in the way.

Warm roof works well for flat roof. Easy to fix PIR down and no heavy tiles to drag the whole thing down no ventilation needed and they often abut walls. Pitched roof is easier cold / intermediate. Need ventilation above insulation. Warm pitched roof is a pain. Very long fixings needed and adds lots of height.

What is the point of the horizontal battens?

I think you need a spec for the lintel, either from your SE or the lintel manufacturer. Cavity wall lintels are designed to take more loading on the inner leaf and any loads spread along the length.

I think 400 centres would be far better. It really will not be much more material, as often there will be additional studs around openings. Which battens are being fixed first, vertical or horizontal?

There will be very little water in the aco as the paving slopes away from it towards the lawn. I think it is getting trapped by the high turf level and the scaff planks.

£60 for an air vent and it looks a pain to fit. I would want to see them fitted and chat to the plasterer who did it before committing.

As per @Conor, there is no spec when they are in the house.

The lawn looks too high and is acting as a dam which is why the patio is not draining.

The joint filler sets a lot harder than the easi fill. I am not convinced either will look good as a textured coating. Why not just get the wall(s) skimmed smooth with multi finish?

The people doing the 3d renders just need the CAD drawings from the architect and site survey people, together with some good quality photographs. You don't need an architect to do the renders.

There is no issue with plasterboard onto the PIR. You will need longer PB screws. It is pretty much what you get with thermal laminate board. I prefer them separately as it means it is possible to separate them at end of their life. Please don't use Fermacell. Massive ball-ache.

Brick acid and a stiff brush. Gloves and glasses.

You could try Mitre Mate.