SBMS

Ah okay thanks @JohnMo I was asking because my wife didn’t want timber internally (chunky) and we’ve had quotes from norrsken, rationel etc that are all more than the pure aluminium system. It seems like a bit of a no brainier for me but wasn’t sure if I was missing something

It’s the Uw. Had the values back from local fabricator.

Have done. Largest privately owned fenestration company in UK turning over 53 million so would hope their claims and testing were robust. What do you think: https://www.seniorarchitectural.co.uk/wp-content/uploads/2023/01/PURe®-Casement-Window-System-Technical-Datasheet-28.10.2024.pdf

Would be interested in why many favour timber alu clad over pure aluminium? Thermal efficiency for us is on a par (0.75 u value eg for aluminium windows). For me the internals of aluminium are preferable to more chunky timber. But would be really interested to know if I am missing something?

Stone slips? Just trying to visualise that.. we are using stone copings on top of the flat roof area..

We are looking at some column and beam casings for some aluminium columns and beams on a canopy. We’ve had a quote from guttercrest which was reasonable. But just struggling with what fixings are needed to attach the square column and beam casings to the steels? Guttercrest weren’t terribly helpful and just pointed us to an installer who wants to charge an arm and a leg. Anyone got any ideas how you’d go about fixing these column/beam casings: https://www.columncasing.co.uk/square-column-casings/

Our architect has designed an open canopy structure that will have a glass/plastic roof and open sides. The beams and column are steel. We’ve had a price to clad these in aluminium which is very expensive. We might have to end up with this as an option but wondered if anyone has any ideas for alternatives? Potentially using composite cladding or anything similar? Be interested if anyone has a similar design. Steel bits numbered in red:

Once plannings approved sort out any pre commencement conditions if you have any - another 10 weeks for us! Depending on your planning this will usually involve getting a drainage design done, construction management plan (ask chatgpt to write one) etc. Depends on your conditions obviously. Whilst this is happening get full building regs compliant drawings done by architect along with any drawings by structural engineer. As part of this you might end up getting a design done for any engineered floors / roof. I would recommend Pasquill for this, they’ve always been good. YMMV. Make sure you get your CIL self build exemption and issue any commencement notices for when ready to start. Next get your SAP and Part l over heating work done. You need to ensure your build is compliant. You’ll need to start thinking about windows, doors etc so you know the u values and thermal bridging details. You’ll need to try and achieve these so your as designed sap aligns with your as built sap. Utilities next. Sort out how you’ll get gigabit internet to property as required for building regs. Easiest is to submit application to openreach. Worst case use starlink. Get quotes for water and electric connections as required. Next step is to organise any self build warranty and site insurance. Then appoint your building control and get your architect to act as principal designer for building regs and submit everything on your behalf. At this stage I think you’d be ready to start although I might have missed something. Obviously you’ve got the appointment of a contractor or if you’re self managing your subbies. Think that’s it!

Sorry @JohnMo I thought you were saying all aluminium units were ‘rubbish’ u value.

Yes this is the Uw value with triple glazed units. Some aluminium units were dreadful - 1.6 Uw and triple not much better. These are Senior’s systems with a polyurethane thermal break.

Our quoted aluminium sliding doors are 0.9 u value. Windows are 0.76 u value. That’s not rubbish?

As someone who went rigid (ahem) with the association attenuators etc, couldn’t agree more. Ridiculous amount of extra kit and complexity for no real benefit in my opinion.

I think the internal 25mm and 75mm insulation will serve as your vapour check layer. Your initial post references this in the Kingspan notes.

Don’t do rigid if it’s a branch system. Was a right pain in our last build. Next build we will use a radial semi system.

When I modelled this it was a diminishing return past 0.15 in the walls. I decided to go 200mm cavity with EPS (traditional masonry) and increasing cavity to 250mm and 300mm made very little difference to overall energy loss per annum. Nowhere near worth the additional cost of the insulation, larger (non standard) lintels etc. Your mileage may vary if using SIPS. Interesting also the comment from Kingspan that their fabric makeup also isn’t SAP compliant which I think from memory was what I discovered. I love the ‘simple application of internal insulation’ - not particularly simple to skin the entire inside of your build with another layer of PIR.. Good wall u values but failing thermal bridging elements hence their recommendation of internal insulation over the timber bridging elements. It was a contributing reason to why I decided traditional construction. That said there are SIPS suppliers that don’t use timber connections and thus avoid that issue.