Bozza

I think you mentioned in an earlier post about using extra liquid, so if that means you watered down the mixture more than needed that may be why. Soz if I’ve misunderstood.

If you go for 18mm if it stands proud of the plasterboard you’ll have to pack out the bottom of the units which will naturally want to pull in at the bottom to the wall and putting strain on the fixings, and making it harder to get nice and level. Sourcing 15mm ply will make your life much, much easier than faffing around. I did something with something similar with my DIY K wall units in my utility room, fitted them onto a horizontal batten then had to brace out at bottom. Big heavy extra high extra deep units. other option would be to put in another lower batten but all extra work like I say having one 15mm not sitting proud is best option by far.

+ I’d do this too exactly as @Russell griffiths suggests. Personally I’d big screw the new ply strip at the vertical joist locations, though it would go through the membrane it’s clearly going to be trapped and clamped and thus sealed. Also some good quality no nails along the length too. makes hanging those big units a doddle.

1. Don’t put a toilet off the the new open plan area. Very awkward. Use the middle of the house eg what is currently the back of the house for the loo, utility etc. 2. Think about natural light in the middle of the house, or lack of it. Rooms that don’t need natural light are the loo & utility & storage & pantry. so top to bottom do decent sized lounge, then utility etc, then your open plan kitchen dining etc.

Adding too much compound is likely to create a lip between the new and old & create extra height where you don’t want it as the compound hasn’t got something to butt up to. Make sure the new compound covers from 1mm thickness to minimise this eg https://www.screwfix.com/p/no-nonsense-floor-levelling-compound-20kg/453hu. I’ve previously used floor tile adhesive as well for levelling small areas, which you can obviously level and feather with greater control maybes better option for your small 40x40 area. And sand thereafter if not perfect. Don’t forget it doesn’t have to be 100% perfect if you’re laying foam underlay and laminate. sounds like you’re close to resolution. if it were me I’d use some self leveller for the very deepest bit of the 4mm section only , being very careful not to overdo it as it would be easy to end up running over to where you don’t need it and thus creating extra height. Pouring short will leave a low valley maybes 1-2mm deep maybes a few inches wide between the exiting pour and your new pour, and then once dry feather in some floor tile adhesive in that valley. Then sand smooth. Won’t look pretty but will be level & will work for your needs.

+1 DIY. I did so myself at at the time my local council took asbestos for free. Buying the required ppe & bags tape etc still much cheaper. my tip would be get a second person to help - significantly reduces chances of damaging the boards. And do it on a cold day it’s hot and sweaty in proper ppe. Get a decent all in one mask if you can. being a low flat roof it should be an easy job. Planks as catwalks, unbolt and bag fixings. stu w gave some good tips. Lift down panels and double bag & tape. Don’t be tempted to pull the sheets down into the garage, lift off from the top and be careful that they don’t scrape on the way down. you’ll have a huge amount of mitigation and don’t forget the asbestos removers do this work day in day out.

Yeah +1 to what everyone’s said. Obviously if you claim stuff that doesn’t quite add up in terms of the stage you’re at / what’s on the plans it risks issues with your claim. But if it’s the stuff like you say kitchen, or landscaping materials you should be ok. I was a bit nervous about a lot of that so I got in a load of material i needed in asap and created my own little builders yard. I got a temp habitation cert with a couple of cheap ikea kitchen units then fitted a proper kitchen afterwards. Claimed the proper kitchen but not the temp one. Wouldn’t do any harm to keep a photographic record of progress at the regs sign off so if they challenge something you can show it did in fact get installed at the house. Agree with Connor put in a covering letter with explanation if anything that may be seen as potentially questionable. I had a few things, did just that and it went through no probs.

I didn’t put anything down but if it were chipboard I would, I don’t think it would make a lot of difference what you use just as long as it seals the chipboard & prevents the chipboard sucking in the moisture from the compound. I’ve used the cheap no nonsense stuff from screwfix with success a few times, ultimately worth a punt because sounds like plan B would be to rip it all up anyway.

In a former home I had a downstairs loo with timber floorboards and low ceiling height. The floor was not level - out by quite a bit despite small meterage - and it was going to be difficult wrong get it level via timber for several logistical reasons including boards going under walls. I taped up the joints and poured a self levelling screed. It was worth a punt and worked really well. A click laminate went over it. whether this would work for you I don’t know. I’d imagine you’d need to prime the osb with pva to prevent it sucking in the the water from the compound. if you’ve never used self levelling compound you do have to push it around a bit to find the low spots. because of my previous success with compound if it were me in your scenario that’s what I’d do. it wouldn’t have to be perfect as you’re putting in an underlay not like you’re gluing down an LVT onto it.

As opposed to caulk I’d personally go for a colour matched silicone sealant, either matched with the units, or the wall colour.

So you will almost certainly require both planning permission and a building control permission. You are likely to need a steel support in the wall you wish to open up. I would however at this stage get a builder around. They are likely to be able to tell you what is required. Based upon your pics, it’s highly likely they will need to raise the ceiling height of the conservatory. A builder will likely be able to advise whether they can do that or not as the conservatory structure might not be suitable for a new proper roof and MIGHT require to be rebuilt as a more robust structure and more substantial foundations to take a proper roof. If you’re replacing that plastic roof with a proper roof that will reduce light into your dining area. You need to think about getting light into that area. my comments are all just ifs and maybes though, until you get professionals in. be of no doubt this work will be a major disruption to you and quite a big job if you want it done right. Including moving the WC. you’ll have to put a mini temp kitchen in your livingroom during such a build. everything you wish to do is possible. If you have the money to do it.

@davelank have a look at my profile pic. We face south. The 3x windows ground floor are livingroom. The 3x windows above are a bedroom. These rooms overheat. Reduce glazing on your south elevation, and you can add a solar tint to help.

@LeeVanCleef if it is by chance the Baillieswells woods land I live 5 mins away. I’d say you would have zero chance of getting a house on there and would be gobsmacked if you got PP there. 99.9% sure it’s greenbelt on the ACC website. Otherwise it would be selling for 20 times its price.

Assuming Aberdeenshire have a look here https://www.aberdeenshire.gov.uk/planning/plans-and-policies/ldp-2023/ if there are no buildings on the woodland to demolish & replace I’d anticipate the answer to your question would likely be No. But Aberdeenshire planning are very approachable you can pick up the phone and have a quick chat with them. The only reason I was able to self build at my plot here in Aberdeenshire was because I did a replacement house. It does annoy me that developers can build crappy houses pretty much where they want but self builders can’t pop a great quality house in a bit of totally unused land.