SBMS

Seems expensive. We were at about 11 for similar amount of windows.

We had the same issue about 8 weeks ago. At the last minute the council panicked because the planners had all been on a BNG course and were not clear as to how to approach this with self builds. Our planning consultant played a blinder here. The council basically said the ‘easiest’ thing would be to prove a 10% gain on our site as we actually clearly have it. Planning consultant stood his ground and said no, that would incur additional cost for us in assessing and undue delays. He drafted this condition which satisfied the council and I believe is now standard for most self builds in the borough to protect against submitting as a self build without any intention to build as a self build and then avoiding BNG. Can you suggest the following as a condition? It’s nice and simple and I think works for both parties “The dwelling hereby approved shall be constructed as a self-build dwelling within the definition of self-build and custom build housing in the 2015 Self-Build and Custom Housebuilding Act (as amended by the 2016 Housing and planning Act): i) The first occupation of the dwelling hereby approved shall be by a person or persons who had a primary input into the design and layout of the dwelling and who intends to live in the unit for at least 3 years; ii) The Council shall be notified of the persons who intend to take up first occupation of the dwelling hereby approved at least 2 months prior to first occupation.” note that as our planning consultant pointed out its drafted in such a way that we only have to have the intention to live it in for 3 years… not actually live in it for 3 years…

We used these on our last build. Much cheaper than residence - probably not as good quality but I would say better value for money than residence. Outside I reckon you couldn’t tell the difference between residence. Inside you could as they are not flush. Very happy with them, they’ve been quiet, good seal and look decent quality

Fair enough. I think it depends on application, we are putting a green roof on so EPDM not ideal and more susceptible to tears etc.

We didn’t end up using superfoil. We went with 180mm PIR because we’ve got the height. I was trying to solution something that minimally raised your roof. Given the option I would use a pure PIR warm roof on deck. But if you are restricted I don’t know why a PIR/superfoil isnt a good option? I’d also look at GRP instead of EPDM. I discounted rubber due to detailing around the roof lights; you might want to consider it.

Challenge here is ventilating a cold roof makeup? We found it difficult to detail with a parapet wall hence switched to warm roof. I’m not sure what you mean when you say the figures are theoretical? All figures are theoretical. Don’t think he’s planning on mineral wool in between rafters as well? I wouldn’t, Not needed to achieve u value and becomes a hybrid roof then

I dont think the ply sub deck needs to breathe (or rather, is susceptible to condensation and therefore needs airflow to ventilate) because it’s on the warm side of the insulation.

Example roof makeup, no ventilated cavity needed, similar to your makeup diagram I think From https://ybsinsulation.com/wp-content/uploads/2022/03/SuperQuilt-Data-Sheet-V3-Feb-2019.pdf there’s also a detail with 4 layers of super foil between and over which hits 0.11. It indicated that a non ventilated cavity works on that as well which would mean your roof height wouldn’t change at all? Worth a chat to confirm with YBS that no ventilation is required? also superfoil acts as a vcl when taped.

2 layers of superfoil on top of joists and 90mm PIR is 0.11 u value. You can reduce the PIR if you’re willing to accept a reduced u value. I think you’ll get that without having to modify your parapet wall. You might have to lift your roof light upstand a bit. That roof (like mine was) will be difficult to ventilate. I switched to a warm roof for this reason.

A 150mm upstand for skylight? As I understand it that’s the minimum for a rooflight. But your PIR depth isn’t governed by the height of your upstand. Your 150mm upstand is from the finished surface of the roof (ie above your insulation).

Thanks @gzoom was thinking something similar for the vertical columns. Don’t know if I can do the same for the horizontal beams unless the steel was drilled to allow timber to be attached before cladding…

Hi all We've got some steelwork at the back of our build - a column and some, I guess you would call it 'fascia' to cover the steel frame that's making a covered terrace (see below). We've had some quotes for aluminium cladding which is pretty expensive. Has anyone had experience/suggestions of cladding the steels for the terrace in anything else? I found www.chamclad.com that looks promising, but wondered if even typical UPVC based or millboard wall cladding could be attached to the steel beams/wrap the column?' We've got another part of the rear that will be clad in burnt cedar effect millboard which might have worked well but no idea if it can attach to the steels..

Thanks @Dave Jones, yep undestand where they'd go. Would they make a big difference to heat loss to justify the cost? Would they negate the need for the 75mm x 210mm PIR edge insulation slab to threshold (and just bring the 75mm screen right up to the edge of the track?

I see - I'd have to reduce the height of the PIR to accommodate the height of the timber threshold? If I did a 50mm PIR and then a 25mm hardwood threshold (or increased the depth of the 75mm screed). Any ideas on how to fix the hardwood threshold to the PIR and the rest of the 75mm screed?

Thanks @Oz07 what would you recommend? Would some 22mm chipboard flooring be more suitable? How would I attach it across/ over the PIR?

Probably LVT. I would imagine a bit of 9mm ply on top of the LVT then 3mm screed over the top and then the LVT?

So in practice you think just fill to the purple line and it'd be okay? I guess it's below the DPC? Any issues with thermal bridging as @Dave Jones seems to indicate a marmox block would be useful?

Does the extra expense justify it? Is there much thermal bridging going on?

Following on from my previous thread... Architect has designed this as a flush threshold detail to help minimise thermal bridging across our triple track sliders, but also provide the 'solid' base that the door manufacturers insist on (they had a wobble regarding having any PIR under it due to them being sliding and heavy). What are thoughts on this as a detail? Not sure how the slab gets poured leaving the haunching in the concrete infill in the cavity - would it matter if it was continuous?

It’s the downstairs one - circled in red on the attached with walls shown:

Thanks everyone

Thanks @joe90 that’d be great. It sounds like there’s options. I can ask our SE and was going to go to Stairbox but maybe a bespoke set are needed

Thanks @nod but that’s what we are trying to avoid

We’ve got a half turn/switchback staircase. I’ve now just realised that we’ve got try and work out how to support the half landing. Timber or oak staircase so no modern steel thing that could be self supporting. Fairly stupidly I now realise, we had assumed that the half landing would be floating - as the staircase is in a corner. But there’s nothing to support it at the fourth corner (layout attached below). We could probably support the fourth corner marked with an X below via a post, or box the stairs in, but would really rather not. Is it possible to build some sort of a steel frame that cantilevers and supports the fourth corner so it floats? Can the half landing be supported by the staircase rising up to it (always read that staircases hang off the floor so need the floor to bear the weight of them, not other way round). I’m no engineer and will probably ask our SE but wondered if anyone had come across anything similar?

What is your planning consultants view? My counsel would not be to focus on what’s existing, reduction in space, existing pool etc. Whilst logical in our minds, they don’t form part of the planning policy around permitted development rights, and I don’t think would be considered on appeal. I think in a full plans application, an inspector might give weight to these facts as there is policy around existing development but I don’t think there would be for PD. I would suggest to others to keep your appeal (if you’re writing it yourself) to the absolute facts and policy on the ground - and that’s the issue of ‘incidental to the dwelling house’. Which I would think is clearly demonstrable in your case. Don’t give the inspector any opportunities to respond negatively to your appeal by including things that don’t serve your application. Be interested to know if the above is consistent with your consultant’s view, or if they think your existing site makeup is material to the appeal?