PeterW

you can use offcuts or just put a piece of timber behind the joint and screw into that.

Put it in the garage if it’s close by..? Or attic space is preferable as long as it’s accessible

Reveals are always done top then sides - a wide reveal you may want to prop the top in a number of places until the adhesive sets. This is where dryfix foam comes into its own as you only need to prop for 15-20 mins max.

Ok so crack on with your build - stick some photos up when it’s done and let us know when the BCO signs it all off as I’ve tried giving you the benefit of 30 years of experience but apparently you know better so carry on.

Ok so using rates I pay and going straight through, you’re at about 185sqm of brick / block. At £1/brick and £2/block laid, that is about £15k of labour at best ... 6 weeks work for a 2+1 gang at good money. Flooring at £15k is mental - that’s £200/Sqm..!!! Are you sure these are not full supply and fit prices ..?? Strip founds in a day would be easy for a JCB although I wonder how that retaining wall would affect the structure ..? Are they 1200 deep founds ..? Is it a brickwork finish to the outer skin or render ..?

ok in building regulations terms, you have an unheated space under a heated space. You need to insulate the space between the ceiling and the floor above. That’s a building regs requirement. I would personally never remove insulation that was required by building regulations under a floor - it’s there for a reason and I wouldn’t do it especially if it had to be where I worked but that’s your choice not mine. The advice I’m giving is based on building regulations - if you’re not happy with it, ask your BCO but they will probably ask for more. I have no idea why you would want to try and build to less than building regulations, they are a minimum standard and not exactly onerous.

I wouldn’t do it ... I would try and create some sort of hollow at some distance down the thread and fill it with epoxy and set a threaded rod in to it and then affix the cap to that.

That is mad - whats included in the price ..? If it’s mixing muck then go with readymix - cheaper in the long run, no mixer and less waste. What are the plans for this house ..??!! Can you post the plans as I think he’s quoting off the scale unless he has included all the scaffold, skips etc. My floor quotes (110sqm of Easyjoists and Caberfloor install) was £1650 and in the end I did it myself. It’s not rocket science and you can easily DIY. Roof pricing round here is about £50 a truss installed. Again, it’s a DIY job if you take your time.

OK... your workshop especially without floor insulation is classed as an unheated space as the floor and door won’t meet the minimum for building regs. BCO is recommending you up the thickness in the walls to compensate for the floor having 50mm, so basically he’s using the uValues to offset each other The space between the joists between your Unheated workshop and the heated bedroom needs to meet building regulations which will be a minimum of 250mm of fibre insulation, or about 130mm of Celotex or similar. If you don’t, your new bedroom will be like a fridge and you’ll lose heat like it’s going out of fashion through the floor.

define the space and the cable spacing and “it’s possible”.... Mat or cable comes in various specs - or watts per square metre - so if you had the 100W/m mat, and a room 5m square then you would have a full load of 2500w on full power, or the equivalent of a boiling kettle ..

yes it it’s - balanced flue. Most - if not all - New gas boilers in the UK are sold and fitted with a C1x type balanced flue that takes the air from outside. Old B-type flues haven’t been used for years on boilers, and are really confined to gas fires rather than boilers. That Veissmann link is very badly worded and close to being factually incorrect in a couple of places.

That is irrelevant. ...!!! Building regs require you to insulate that floor / ceiling as it is a ceiling above an unheated space ... you have no choice and it should be a very good insulation layer.

It’s nothing to do with air flow, it is to do with not creating a negative pressure situation around a casing that could pull fumes through a faulty seal. All boilers need airflow around the casing to both allow the heating and cooling of the casing, vent any minor gas leaks and also to stop any possibility of a negative pressure being created around the boiler.

Looks like horse box flooring ...

1. Could happen in a standard shower tray 2. Decent designed in falls and a screen will stop this 3. See 2. 4. That’s down to poor ventilation and extract, not just a wet room. If you design it in, there is no step down for a tray. I’ve done one recently with a big 1500x900X35 tray that is recessed into the floor panels and when tiled up to it, there is a nice 5mm transition ledge into the shower. A 1200 screen stops any over spray. 800 square trays are tiny when you try and bend to pick anything up, and 6 or 8mm glass will not stop you falling ..

So you’re going to buy £250 of insulation and flooring and then rip it up and bin it a week after sign off ......??? I would plan to leave it down and put 140mm in the walls as per BCO and get yourself a decent warm workshop. In reality how often do you stand vs sit when working ..??

Ok so definitely 50mm

It only has a 40mm drain... 50mm when buried under the floor is preferable. How far does it have to run..??

For the sake of £10-12 from S'Fix/T'stn I would just fit one. No as it will move, and why would you want to..???

Also worth using decent extraction and a dust cyclone when cutting, routing or sanding Fermacell as it’s evil stuff. The dust gets everywhere and even through filters on hoovers and you destroy the bearings.

I would do floor, electrics, ceiling, walls in that order, burying the cabling in the walls. Other option was to put the power cabling into the ceiling space and insulate it, fit the boards and pull the cabling in surface ducting to power sockets and switches. Easier to do as you don't need to worry about finding back boxes etc

https://www.rutlands.co.uk/sp+premium-10mm-dowel-jig+R6012 £9.95... Assuming they don’t want £30 shipping @Stones

Insulation onto the floor, friction fitted. Lay a plastic DPM (sheet membrane) over the insulation. First caber board groove side up against the wall and into a corner with a couple of spacers to give you expansion gap (8-10mm) Measure next board to fit to the gap and check for fit. Glue the tongue (foaming D4 is best) and fit the board tightly (use a board off cut and a mallet to keep the joints tight) and then leave the glue to dry and go for a cuppa. Take your off cut and use it to start the new row so you get staggered joints. Repeat as above... once first row is dried the rest can be done from that one.

B is correct in your picture. Cut the Fermacell slightly over sized and finish with a bearing bit in a cheap router running over the face. You may need a small fine tooth saw to square off the corner. You can snap and score the reveal boards to fit with the rough edge on the inside of the routed edge, then just fill any gaps. Leave a 2mm gap from a factory edge to the frame and FST and paint the boards then finish with a bead of decent sealant between the board and the frame of the window.

errr... grey box on the main iPad screen ..?? then.. Settings > Passwords & Accounts click on the account in question