pyros

Hello. I stumbled across this fabulous place when looking for examples of submitted building control plans - and feels like a great group of like-minded individuals. I'm currently working on converting my garage (in England) in my downtime, and was hoping for a 2nd pair of eyes on prepared statements / drawings before I submit my (a) permitted development application and (b) Building Control notice. On the latter I feel some confidence there's an iterative process if details aren't exactly what's needed, but not so sure on the former(?). I'm a mechanical engineer by study, and a systems engineer by profession. And an avid DIY enthusiast. So all the work needed (minus certified trades) feels within my gift, and that's great as it saves £££ towards other costs, I just haven't found a conclusive list to ensure I'm checking all the boxes. Although believe I'm hitting all identified in research! (subject to a few queries I'll get to below). I did try contacting a few firms around double checking, but they generally seem more interested in selling me a full drawing package. Overview - now Garage is 7.65mx3.05m and approx 135mm below house floor level. Attached, via the utility room. Single skin brick wall, although the front aspect is double skin (as in 200mm thick, not a cavity wall). The brick walls have a DPC that's approx 75mm above ground level and is floor level inside the garage. The garage has a pitched roof that's shared with the utility room & hallway beyond it, that's partitioned off with blocks. The roof did have a couple leaks that I've had repaired ahead of this work with some new felting and re-pointing. The wall has a shoddily cored 100mm exhaust outlet that was once for a gas heater (long disconnected and gone) - I think they must have used a SDS chisel instead of a core drill and left it a mess, so planning to cut out the 4 impacted bricks and replace and re-mortar. This is the prepped 'shell' I am working from. Summarised my plan is.. Firstly floors: D.P.M layer on the concrete (lapped up the walls), and a floating timber floor (38mmx89mm) sitting on top, with 400mm centres and 600mm cross-supports. Within the frame I will insulate with 75mm boards with a 14mm airgap below. I will then top with 18mm chipboard, 5mm laminate underlay, and 12mm laminate (these last 2 will be done when all the works are getting there of course). The U value works out to 0.22. The increased floor height will be +125mm, so just 1cm drop from the main area which I'm inclined to accept. Secondly walls: Breather membrane on brick lapped with the D.P.M., and timber battens installed (38mmx63mm) with 400mm centres. I will insulate with 50mm board, with a 13mm air gap behind. I will then top with 55mm insulated plasterboard. The U value works out to 0.25. The wall upgrade takes up 10.8% of the floor area - I understand from the exceptions notes in the building reg for insulation that if insulating takes >5% floor area, there's flexibility, but I'm keen to have my future home office nice and warm even if the insulated plasterboard is ££££. There is an 'internal wall' to the utility room, but right now I've treated all walls equally, as the utility is kind of cold and I don't think wall insulated having met old BC regs when built x decades ago. Thirdly ceilings: 100mm bottom roll among the 100mm rafters, topped with a 200mm super top up roll, leaving a 50mm gap on the eaves for ventilation. Some of this is lie-down crawl space only. Despite my hesitations with going near decades of thick cobweb build up, I want to affix breather membrane to the counter-battens and lap it with the walls', just to protect against any potential future leaks (the roof is a bit aged and another contractor suggested/quoted for re-setting the whole thing to correct the previous leaks, but my 10 year plan sees us extending upwards anyway, and this killed my budget). On the underside of the rafters, 12.5mm plasterboard. The U value works out to 0.155. Kinda close to the limit of 0.16, but if I can avoid the extra £££ for insulated plasterboard here when I already have 300mm insulation I would like to. Then some partitioning / plumbing Stud walls with 9.5mm plasterboard and some kind of sound insulation to partition the rear 2.3m into a 1.2m wide storage area, and a 1.5m wide bathroom with shower, toilet, sink. One element of the house's foul drain system is piped conveniently below the garage foundations at 200mm deep, which I intend to break into for foul drainage here. For the bathroom I'll also get an extractor fan installed to meet BC regs. The garage already has water for an outdoor tap and will just need some additional piping. The utility room already has a radiator, so my plan is to extend the central heating system into the garage with a nice high BTU vertical radiator. I intend to get in my plumber to tackle the infrastructure jobs early on, but leave the actual bathroom fittings a fair while so as to spread cost. Replacing the garage door Local door manufacturer and installer to replace the garage door with double french doors and a side window with opening top panel, at the increased floor level. Need to pin down exactly what they'll do in elevating it. Now question here.. I've seen lots of talk of how SE calcs are needed for a brick wall, but a door is a lot lighter, so do I need to get these calculations done for BC purposes, and/or is it something I can expect of the door installers? (who will do self-registration as their doors meet BC) Electrics Qualified electrician to expand on the current ring main providing 3 double sockets and a light, to add more 13A sockets, lights, shower termination, switches, etc. On this, I've read lots on how wiring should be above insulation in the ceiling, and obviously I want to see it done before the wall upgrades are finished so it's neatly behind, so in terms of sequencing should I be looking to get electrics done ASAP? That took a bit to get down! I think broadly a solid plan, but open to any criticisms on things I've missed, or tips on helping this along. What I'm focussed on right now as I prep the garage for works is the permitted development application, and prepping BC drawings for a BC notice. Pretty confident the work is valid under permitted development, especially since there is no covenant against something like this, and PP for the garage (in '87) has no stipulations removing the right. What I'm not 100% sure on for permitted dev. application is (and if anyone has an example that's been approved then please point me to it): The level of detail expected on the application If when they ask "Does the proposal consist of, or include, the carrying out of building or other operations?" they mean what I'm doing, or if they mean building a new structure. Right now my prepped form says Yes to this, and in 5 bullet points outlines the big ticket elements detailed above highlighting it's strictly internal with no footprint expansion. In verification evidence they ask for things showing timelines etc - I've input my quotes received, but don't know what else I might stick in there. Other than my BC plans. What I'm unclear on ref. BC is: The local council only IDs charges for a building notice and plans review (for a garage conversion specifically) - does this mean no site visits are needed? I only have a form for Building Notice - do the plans follow later on at request? I've drafted BC plans to submit based on examples I have seen around (incl a couple on here). If anyone can sense check these with a 2nd pair of eyes, I would appreciate it!! I have drawn them in smartdraw which I went and bought a license for as it seemed nifty for this and other work stuff, but I've been unable to get all my drawings on the same page - is it a problem that the necessary views are presented over multiple pages? They're all still to scale etc. I'm remiss to re-draw in another tool as there's a good few hours of work into these.. That's it! Again any thoughts/tips/suggestions warmly welcomed. I feel like my planning is in a good place. I'm hopeful over the next 7 weeks of weekends (and probably a week of focussed time) that I might be able to do the bare floor/walls/ceiling, but not sure how realistic this. Definitively it needs to be done by July so that my old office can become a nursery! 702110592_20230120-GarageconversionplanswithoutSite.pdf