Dave Jones

id do. 150mm hardcore 300mm EPS insulation 75mm fibre screed (no need for metalwork). ASHP as others have said IF you can get the barn airtight. If you cant it will struggle and as you have read be expensive to run. Guessing the barn doesnt have a DPC so you will need to get over this, painted on etc.

how much have you paid for the quote ? Takes a lot of time to do a detailed quote, expecting it for free sours the job from the get go.

150mm hardcore (100 absolute minimum), 100mm celotex or 150mm EPS (cheaper), 75mm screed.

you want the lining to be the full width of the wall will look crap ottherwise. Make one out of a sheet of 18/22mm mdf.

not that ive seen. Standard 2x1 .

junk math. Lorries use loads.

render .......

the BCO doesnt know that its going to be upgraded. Silly.

did you post pictures of the finished article ?

Still waiting for why a structurally fixed lump of timber isn't permanent. Regs do not say it has to be pretty.

what's not permanent about it ? Is plasterboard screwed to wall not permanent?

maintain 50mm air gap then fill with PIR and overboard with insulated plasterboard. You are going to lose a bit of head height but at least you wont freeze taking a bath!

no issue at all. trenches often have a couple inches of water in them when conc is poured for example. The problem is when face brickwork is not dry and it rains, struggle to ever get the staining out of the courses below.

some say a nails width gap? Our last build had a large flat (warm) parapet roof (10x6), i butted the OSB (cheaper than ply) up tight and had zero squeaks, movement.

why hemp build ? Creating a headache and cost right off the bat. Excellent insulation levels can be achieved much more cost effectively with normal traditional build types. Save the money for elsewhere!

one of the few occasions ST is correct!

i use roomsketcher, 10x easier to use and it properly 3d renders including furniture .

why ? It complies with regs.

how can they fit it wrong, its tongue and groove ? Maybe your local brickies cant tell up from down!

fantasy prices. Like a brick costing £12 before discount.

prepare to be royally bent over. ASHP from city plumbing 2-3k, tank 1k. daylight robbery by plumber 10k for couple days work.

recticell all day long.

save yourself a lot of hassle, have 400 GAPS not centres so when you rip the PIR you have zero waste. You may need an extra truss and spend 10 mins making the plasterboard work but will save hours and £££ on the hateful task of insulation ripping.

sheet of ply screwed over the glass to 800mm above floor. pass inspection. remove ply and fill the screw holes. end of drama.

yep thats them.