Thorfun

just to add, as you've got to re-tile the roof have a look at a breathable roofing membrane and batten/counter batten build up above the rafters as then you can fully fill the rafters with 100mm mineral/glass wool. obviously check with your BCO that they're ok with that method. ours was but sometimes they differ in their opinions!

put glass wool batts between the rafters as they'll 'squash' to fit the wonkyness to some extent and then put PIR internally. would mean you could reduce the amount of internal PIR and still get the U-value you want.

this is good to know. although many on here recommend to glue directly to the 22mm chipboard for a more solid feel rather than a floating floor.

you make very good and valid points in here @Gus Potter and maybe i'm being a bit guilty of trying to do too much and to tick too many boxes! our kids aren't little and so there isn't a lot of stomping around in their bedrooms (they generally sit on their beds and watch YouTube vids!) and so may double boarding is simply not required. we've already put 100mm of Rockwool between the joists and if i use resilient bars and a single 12.5mm board then that would probably give a nice sound reduction level. then we're building within the original specification and i save money on a second skin of plasterboard and also SE fees! i guess that's one issue with self-building and reading forums is that it's hard to resist the 'ooohhhh.....i need to have that!' temptation when you read about something that sounds like a good idea whether you REALLY need it or not.

You’re very helpful and don’t let anyone tell you otherwise. 🙃

i really think you're doing the right thing and not just for your marriage's sake! well done and keep up updated.

i can't comment on that as i'm not a structural engineer.

according to https://www.bauder.co.uk/contact/frequently-asked-questions/faqs-green-roofs their lightest weight sedum blanket is 44kg/m2 maybe figure out the system you want to use first and then work backwards to figure out if your roof can take the load

Was actually in a rush to leave the office.

Your thread is like a bible to me and I refer back to it often!! thanks for the weight of the skim, I was wondering what that would be. definitely loads more to think about and to consider other options. I could do 12.5mm and 9mm as a middle ground. So many options.

so true

Hi @Gus Potter. thank you for the response. i do actually have all of the SE calculations for the TF and i think i have them for the basement. The load bearing walls that the joists sit on are 140mm CLS timber walls. the external walls sit on 250mm reinforced concrete walls which sit on a 250mm reinforced concrete slab. the deflection of the joists were designed to be 8mm so we don't get any sort of bounce in the rooms above. do you think that for peace of mind i should engage a structural engineer for this? i can then give them all the information i have and ask them to calculate if double boarding will screw stuff up? if so, how much do you think something like that would cost?

You described my work perfectly!! 😊

Also, I read others on here had issues with EPS70 and UFH staples not staying in and destroying the EPS. I had no such issues with EPS100.

According to Jablite who I phoned on this subject EPS70 is fine for standard domestic loads under a screed. They said if it was for a gym equipment or heavier loads then EPS100 would be needed. For under our screed I decided to go for EPS100, not because I’m putting a gym on top but just for peace of mind in case loads increase (although I wonder what the block and beam load is specified at?) and the price increase was minimal and still half the price of PIR!

Will take a look. Cheers.

I read that as don’t do it myself! 😂

It’s more what SWMBO has decided on for tiles. I’ll pose the question of mosaics. Will also ask the tiler when he comes down. I can’t make the linear trays work as we have 300mm centre joists and they’re really wide as well. So only about 150mm gap between the joists and as is Sod’s Law the joists are exactly where the waste will be and we have a double joist there too! So would have to build the wall out about 150mm to make it work and it’s already a smallish shower area. So the easy fit formers with the rotating waste works better for us.

Oh! I thought with the slope a tile would have to start at the former as they don’t bend! So there’s be a line where the former started. ok but aren’t mosaics on a webbed backing so they’d bend/angle down the slop of the former?

I am concerned about having a strip of 100mm tiles looking a bit strange at the end of the former is all. I’ve no doubt it can be done just concerned as to how it will look.

We are. The Impey Easy Fit formers. You surprise me!! 😂 obviously I meant I can cut it down to give a reasonably sized flat bit as part of the entrance.

Could be a while then

not strictly true. you could get a standing seam roofing company to do the roof, a chippie to do the cladding and the window supplier to install the doors and windows. no need to pay the overhead of a main contractor for that stuff as far as I can see, unless you're wanting to reduce risk by paying a main contractor. we did ours with separate trades and worked well.

actually, thinking about it, I can cut down the 1300mm x 800mm tray to whatever length I want (within the limitations of the tray as specified by Impey of course)! 🤦‍♂️

I spent this morning removing the crack mitigation strips and extra dpm from around our newly laid screed. definitely not been idle!