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@LSB, that's very interesting. Also a novice builder in Suffolk I'm PM'd you.

Ah, that’s it. Do you know if the change in practice applies both to public and private inspectors?

@mjc55 It's been a topic discussed a few times on the Self Builders forum on Facebook. Mind you, my LABC told me today that "our Building Control Inspectors will carry out inspections, and if you require any clarification the inspectors can provide advice on your project" so perhaps it is a local authority specific change (thankfully not mine).

Thanks all for the feedback. I'm minded to go with LABC but I've heard that recent changes means that LABC inspectors cannot offer advice any more, only pass/fail works against the building regs. And that private inspectors are able to give advice but can't enforce the regs. Any thoughts on that?

Ah, sorry! The private inspector is £700 more than LABC.

Hi. For building regs control my architect has proposed LABC or an approved inspector that costs £700 but can’t explain why I’d pay the extra. Can I have your thoughts on the pros and cons please?

Hah, now you've made me go back to check my quote from Turner! And yes, I have that wrong. I confused them with Fleming (who only supply the additional insulation). Going to double check now that I've made the right decision to go elsewhere. Still time Did Turner also provide you with an insulated roof? Your choice of 0.09 for the walls will go some way to mitigate the thermal loss from your windows. What U values did you end up with for your glazing?

I was wondering about the performance numbers, thanks for sharing. Did you add more insulation over the insulation we saw set into the frame? We couldn’t find a TF company that could achieve 0.09 without extra layers of PIR. Triple glazing seems to be the next step for efficiency but I guess with your widows that would have been very expensive?

Finally got to watch the show. One of the best GD episodes ever. Under budget and ahead of schedule so it CAN be done. I’ve been following your Instagram channel from the early days so I have an idea what you’ve gone through to get to this point. Well done.

Which I find incredible. Your choice of materials has been excellent. Not cheap mind, but has upped the standard I want for my build.

@BUBBLES67 Did you find a good solution in the end?

Now I look back at my quotes I can’t find one from Aerobarrier to back up my £6k so ignore me.

That’s what they quoted me for a 180m2 house.

FYI, I have decided to go with MBC's Passive system. Yes, there is a premium, but once I started digging into the details of other offers the list of uncovered work got longer and longer. For me, the lack of thermal bridging and the promise of an insulated, air-tight, wind and weather-tight finished frame justified the premium. Just.

Cheaper here: £54. Probably shipping and tax on top. Same product though as far as I can tell. https://www.aliexpress.com/item/1005006216842254.html?spm=a2g0o.productlist.main.49.706fa3Spa3SpBs&algo_pvid=99a4c398-362c-4cad-8d1b-eba9e5600680&algo_exp_id=99a4c398-362c-4cad-8d1b-eba9e5600680-24&pdp_npi=4%40dis!GBP!106.78!53.39!!!135.75!67.88!%40210387dd17260731937254697eddc0!12000036322462749!sea!UK!889673203!X&curPageLogUid=KRqsJZNZNPs7&utparam-url=scene%3Asearch|query_from%3A There's a lot of UK companies reselling stuff that we can get direct from AliExpress. I guess they offer a degree of quality assurance and convenience but sometimes the mark-up is fierce.

I’m finding the opposite. Fleming’s quote was almost 50% more than KTS/Potton. However I’m finding Potton very hard to pin down to one price. They keep presenting a low base price with options that aren’t actually optional. Like the roof insulation.

Twenty years from now I don't think so. But it's got me thinking about the embodied carbon in their products.

@Kevin Dawson I'm heading that direction. Need to make a decision very soon. Happy to compare notes

Yep. This is another factor. No one is perfect but corporate culture is hard to change.

I suspect that's exactly what they do. Mind you, a big part of ensuring safe design and practices is knowing what might go wrong and what questions to ask. That requires experience that I don't have so. If I could find a decent project manager who will work for a fee instead of wanting add a margin to all the works they procure for me then I'd lean on them. But I can't

Correct The PD’s role is to consider the safety risks of every design decision and mitigate them. It is not to lead the design - that’s the architect’s job.

Agree. I feel happier about my duties there now I’m covering off the PD role with SafeScope.

Frame were even more expensive than MBC for us. Fleming couldn’t supply thermal modelling of their system and left a lot of work to others to finish for my tastes. Our architect is doing the building regs. They will incorporate the details from our SE (foundations) and the TF supplier. I have. My KTS quote stated they will be the designer for their part, but NOT the PC or the PD for the whole build. I think Potton, sister company to KTS might do more perhaps? I’ve discussed my approach to CDM here:

Absolutely. Looks like we will be building through the winter so we want to get to wind & water tight ASAP. Yes, no different. KTS seems to use a timber I beam for the window lintel which performs better than MBC's three-stud lintel. MBC use their TW blown cellulose frame for the roof on their Hi Performance system so much less work left to us to cover. Sadly that's not the case as the external footprint is set by the planning approval so we have to work in from there. Our planning app site layout was done assuming 500mm walls so the internal space is still generous for a three-bed.

Hi. We have planning approval for a two story new build in Suffolk with a treated floor area of 200-189 m2 depending on wall thickness. I need your help to pick a TF supplier please! My shortlist is MBC Twin Wall, MBC Hi Performance, or a KTS Ultima system. I want U of 0.12 and 0.6ACH with minimal thermal bridging so I've discounted suppliers that can't provide thermal modelling to evidence the performance of their systems. I did look at ScotFrame but they were stupidly expensive. KTS Ultima 140/55 has some thermal bridging issues around windows and a lot of on-site work for others to complete the insulation and air tightness layers. I'm estimating £15k in labour and materials to get down to the PH 0.6ACH standard. My amateur PHPP calculations indicates the building can't quite reach Passive House standard. MBC High Performance is very similar but has slightly worse thermal bridging issue around windows. They leave much less work on site for others to complete. MBC say they usually get down to 1.5ACH, so I'm estimating £6k to get to 0.6ACH (using Aero Barrier). The PHPP calculations indicates the building can just reach the Passive House standard. The MBC quote then works out £19k more than KTS to meet my requirements. MBC Passive is a twin wall system with almost no thermal bridging and comes with a 0.6ACH guarantee for the finished structure before first fix. It also uses cellulose insulation so has a much lower embodied carbon. The wall are thicker through (500mm) so the floor area drops to 189 m2. The PHPP calculations indicates the building can meet the Passive House standard. The MBC quote was £33k more than KTS to meet my requirements. My heart is saying go with MBC Passive. My budget says maybe KTS. There are other factors in play of course, such as reputation of the supplier and their customer service. What do you think?