matthyde83

I cannot agree enough. Just had to undo about £6k of work that building inspector told us to do a week ago and now told us we were right in the first place!! No returned calls. 2 weeks at least to book an inspection. No response to queries on plan checks. I am dreading dealing with them for the rest of the build and ultimately getting sign off!!

Sorry to hijack… I have a tv room that is separated by the rest of the house by a cavity wall. I’m using thermabeads everywhere else but there’s the opportunity here to put something different in the wall to increase sound resistance… 150mm cavity. What are thoughts?

Mind me asking who?

Im in the process of making a complaint and requesting he never darkens my (yet to exist) door again but await how successful I’ll be. Positively he’s not now back until roof at least and we’re just tearing out the cavity tray and XPS so the beads can go all the way to the bottom of the cavity.

I’m really struggling to find a blown cellulose supplier and installer near me (Surrey). Any suggestions?

How come you stuck with 400mm centres when you have 400mm deep joists!? I’m expecting if we’re changing from 150mm and 175mm joists to 400mm engineered then one of the savings to offset will be increased centres? Maybe it’s because of the cavity batts only being in 445mm sections though?

Which rock wool product did you use and at what joist centres? Majority seems to be for cavity walls and therefore 455mm wide? How was the cost at 400mm depth?

So this gets even better… we’ve spent the past week getting XPS and cavity tray in. 80% of the way around and building inspector comes back today. On second inspection he now agrees that the cavity tray will do more harm than good. Suggested not bothering where we haven’t done it already. In one area he’s suggested cutting it and lapping it up the inside of the exterior wall and in another he’s suggested piercing it with holes so that it drains. I am absolutely furious. With XPS and labour I reckon it’s cost the best part of £5k-£6k and basically he now thinks it’s pointless.

I’ve got handmade clay tiles so plenty of gaps!

Sorry I meant so the blown cellulose would create a constant layer. Not cheaper…

I imagine with I or metal web it would be even better? How about vermin? When I demolished the bungalow that was there the roof was chock full of every kind you could imagine, and some you couldn’t!!

Are they lined outside or just membrane? I think I joists may be the way to go but not sure given my roof layout.

Thanks. Is the 400mm to allow for Rockwool rather than PIR? Is that due to cost?

What build up would you suggest for a warm roof? And if I’m insulating on top of rafters do I need to set rafters lower so that overall height of building doesn’t contravene planning?

I’ve looked but my roof really does not lend itself! 54a1 f.pdf

Thank you. So this achieves the stated 0.16 for the pitched sections. I can imagine this being quite costly though? 9’x2” instead of 4, OSB layer, glasswool and 220mm blown cellulose… Can you tell me why the recommendation?

I’m trying to make some decisions on roof insulation on my new build… So far I’ve increased the cavity to 150mm and using EPS Beads, increased floor to 200mm PIR. Now I’m tackling the roof. I have a few different sections. Mono-pitched on ground floor currently specced as 150mm rafters at 400 centres, dormers with similar and a hipped section specced with 400mm loft roll. Reading through building regs submission it’s suggesting 0.16 u value for mono pitch using 200mm celotex and 0.11 u value for the loft wool sections. I’d really like to hear people thoughts / advice…

Does anyone have any recommendation for an SE I could get a second opinion from?

Oh and 20mm plates and stiffeners everywhere. Over 5m and 300kg of 20mm plate in the one beam and connections.

i suspected over engineering as much. So far we’ve had a slab with two layers of 10mm mesh and B5 has changed to a 451 UB 97. Fabricators struggled to locate one so short as they usually come in 30m length for railway bridges!!

That might make more sense but a lot are labelled as UC and they’re definitely not. B5 etc. Below is the connection detail which also indicates it’s in the gf ceiling…

Also Trimmers shown. I’m assuming they’re to support the ridges but it’s a hipped roof so they can’t be at ridge height else they’ll be sticking out the side. Also ceilings will be sloped as eaves height is quite low so they’d need to be below that?

Ok… one of my main questions is B14 and B15. Where are they? They’re labelled as in the gf ceiling but also labelled on the roof plan as ‘under’. Also what is their purpose? They are below a stud wall, if it’s support for that then can we not double joist to allow for MVHR etc.?

He can’t. One of my questions is recommendations on here really. I can google obvs.

It’s been a month… plus architect has said he’s talking to him on other jobs. He’s trying to talk to him about mine also and getting no luck.