Oz07

Seen full lead tray on some dummy chimneys on a job last year. Couldn't work out why they didn't use dpc myself. These still leaked through brickwork last winter anyway. Builder sealed with water seal and fixed problem

As @Judy C says above I've used that exception before. You would have to set up a company to invoice yourself though

Think it's more direct transmission ie studs. Hence why resilient bars on ceilings to decouple is so good

I don't think there's any quick and dirty rules of thumb so many variables. Area you're insulating, volume your heating, heating source etc etc Jeremy did a spread sheet I've had a play with but still then you have to start working out energy needed it's like black magic to me. What size is your batten then 45 or could you swap down to 25mm lath? Do you think the price difference is more pronounced due to uncommon our size? Perhaps price based on 75 or maybe even 100

Maybe more a grano mix would be suitable. Bit of dusty granite chippings and sand with cement. Same as a drainage benching mix. Then some additives to help finish sbr or waterproofs.

Have always just put onto screed on any job I've fitted some on. Obviously I've not specced these just fitting what's infront of me. On mine I usually sit ontop of agilia as min 75mm thick. Chucked a sheet of mesh in last place as had a structural newel taking small floor load. Architect wanted newel taking through screed insulation down to floor beams. Sounded a nightmare to me and recipe for trouble maybe rotten newel?

2 issues here. Did they eventually finish the job of insulating or did you or your plasterers? Did the waste really fill a skip. I'd be interested what their quote/contract says about waste/cleaning up. Most building sites supply the skips with subbies having to put their crap in them themselves. I think your time for cleaning up would be fair, not sure about the cost of skip

Where in country that sounds dear.

I always land short ends on joints. Lmow another chippy who was made to go and not underneath with some h section shape nogs by labc warranty. Learn from others mistakes. Probably nessecary and probably be fine but not hard to do

Wouldn't waste too much time working it out. Rough and ready will do. End of the day it costs what it costs and you always need more than you think. Eh @Red Kite?!

Why can't you share publicly. All sound interesting and obviously you're not here touting for business. The pre cut supplier sounds interesting. Why change their specified insulation?

At a similar point @Russell griffiths was going to attempt myself but I don't know how much spare wire sparks will want and what kind of run/route would be preferable. Got him coming out next week to put the cable in for me should only take an hour with scaffold up. My soffit is fixed to underside of 50mm battens, I presume he will run cable ontop of these and leave un clipped. Do you have something like this? Think cables are supposed to be 50mm up off ceilings or things like that @ProDave?

Surely your posi supplier will give you a fixing detail. At end of the day they're the floor designer no doubt there is some excellent knowledge here but you need to be using an indemnified professional

I think structurally you'd be better off flush at the bottom gap at the top. If you look at a joist hanger its not normally as crucial at the top. Hasn't this detail been specced by anyone though? Floor supplier? Steel design guy? Sometimes the posi's can have extended top chord which could work with your steel sizes?