torre

Personally I prefer to choose architect and builder separately, on their own merits, so I'd treat this as a recommendation much as you would from someone else; consider them but don't feel you need to give them the initial brief in hope of securing the builder. I didn't quite understand this - do you mean the builder wants to charge you and they'd be engaging the architect? I definitely wouldn't consider that, I'd want to be engaging any architect directly at any stage. One of the challenging aspects of a self build is that yours is a one-time deal, whether for the architect, builder, or suppliers. Most will want to maintain their long term relationships with each other and the closer they regularly work together, the more that may mean they lean towards each other rather than to you when things crop up, big or small, that need a solution further down the line.

Don't forget to send your CIL commencement notice. You should be fine to clear the site but If you're going down the full plans route for BC and haven't submitted yet I'd try and speak to them before doing anything else.

Yes, nothing to claim back off scaffolding @nod but you shouldn't be charged VAT on the labour of erecting and dismantling in the first place. HMRC guidance

Our scaffolders were happy to show hire and erect separately, and zero rate the erection

I think the only advantage is for the developers, who can get away without the cost of installing MVHR

Buying a hoist was probably the best £100 we spent and it sounds even better value now!

I agree with @Redbeard this is likely to be amenity land you own but it's use is restricted, so clearing a large area and parking a car there may not be allowed. Could you remove a much smaller part of the hedge and park parallel with your existing drive& garage? They way you only pass over rather than park on that land. It does lose more garden but it's less likely anyone will kick up a fuss

Helps preserve the listed building by financing necessary repairs, creates local employment are a couple. Did the planning officer give any indication of the public benefits they considering when weighing up? Does your council have an up to date local plan? If not that should tilt the balance further in your favour. It's good if you can already offer some mitigation for the points raised and your list of benefits already sounds good. It'll be harder for a planning officer to justify refusal of a full application then at the pre-app stage and I'd expect a planning consultant could get you over the line with this one. (We had to overcome less than substantial harm in a conservation area rather than re a listed building)

What's your plan if family circumstances change and they need money back? If you may need a mortgage in future you'll need to budget for some sort of warranty, also if you end up needing to sell. Your house looks well suited to being built on a budget but you need to plan for worst cases and have contingency. What are ground conditions like and service access? So much money can go just getting out of the ground. It's an exciting plan and I want to sound cautionary not negative but if you risk running out of money an unfinished, unwarranted house may not be worth much more than the land it's sitting on.

Roller shutter door fitted just forward of the opening with the roller in your soffit space might be an option. The rear wall construction will be for stability of what's otherwise a tall half brick wall

Search for "decorative mouldings" for example these

We've used facing below DPC, but you have to check their frost resistance rating. You're looking for an F2 rating.

Interesting idea but don't you need around 3600 cut lengths of pipe that size? If it's not available cut then I can't see it's worthwhile cutting pipes yourself. The compressive strength may well be questioned by BC. Maybe this would work better with pipes the length of your soakaway all laid the same way creating a stable honeycomb shape like you'll see when pipes are stored in a builders yard? (Around 100 pipes of 3.6m length) Either way you'll still need the whole thing wrapped in a membrane.

Why not fit 25mm insulation between the cross battens? Avoids any deformation and improves the insulation level.

Another alternative might be to fix the diaphragm to the underside of the joists, but you'd have to check with your SE.