Conor

Bed and cover, use as you would normal dust / gravel for pipe trench fill. The public surface water sewer that was installed alongside our founds was done exactly that way. Bed of lean mix ontop of our loose stone backfil, and pipe was covered in more. Remaining levels brought up with loose stone.

Get them on to their own radials.

Lean mix. Used all the time for this sort of thing. Cheap and easy to work with.

The NIW application is a single page and takes about 10mins. You can always just replace your side of the service with 25mm mdpe which will give a big improvement in flow. The NIE is online and is two sketches and a form. Don't see why you'd pay someone to do that. NIE are surprisingly quick at the minute. I put an application in a couple weeks ago and I've had to push them back as they wanted to do the works next week!! But saying that.... There is sooooo much to do on a self build even if you're not doing any hands on work yourself. We got our house watertight at the end of July at the tail end of the heatwave. The house stayed cooler than outside. Same this week. If you're architect has designed the house to be passive, I highly doubt you'll need the external shutters. You're spot on with you heating strategy. We're going to ashp and ufh in the basement and ground floor, omitting the top floor. Just the two zones. What size is it? If you are north of 300m2 you should consider two mvhrs. Our build is ICF, but you're welcome to call round for a nosey as we're at the interesting first fix phase.

For our roof, the material costs went up 6%. We split the difference at 3%. I'm finding it hard and harder to get people to do supply and fit, they (joiners, roofer, boarders) want me to buy the materials and they just do the labour and sundries.

No sympathy. We delayed 3months mid way through the build waiting for an amendment to put another story on a 3x4m flat roof that isn't even visible from the front. Wonder if there was an architect involved? Hard to believe there was. A glance at a proportions suggests a DIY design. That door on the LHS ffs... The copy and paste windows...

You'll need straps for that length of beam. The handler will need a reach of 3m or so greater than the actual distance. We used a 14m handler to lift our 6m beams up our. 1.5 stories. It was quite difficult to maneuver in our site. In hand sight a crane would have been a better job Have you ordered the beams? If not, shorter beams bolted together would be easier - that's what we did.

We recently put on thermohouse roof panels. A few points. A fast installation and good value if you have a simple roof. Gordon from thermalshell construction did an excellent job. Dormers, valleys etc really add to the install time and cost as there is a fair bit of wastage. Ours took just over a week. Cost was about the same as a cut roof. They are not entirely waterproof when done. We still had loads of water seeping through at abutments and valleys. So you still need your roof fully finished before starting second fixes. A fair bit of additional joinery required - soffits and facias need to be built out, more so than on a timber roof. By far the biggest pain is all the counter battening. Needed on the top of the roof to take the roofing lath. I had 900m to do. But by far the biggest issue is on the underside. If you are going for vaulted ceilings or fixing anything to the underside of the panels, it's a massive, expensive pain. If you are boarding, you need to batten at 400mm centres. Grounds for electrics are also required. There's nowhere to run cables. You need to use 180mm long harden steel screws (timpco velocity) to fix through to the steel channels. They are £45 for a box of 100. We got away with a cheaper alternative at £30 but we're harder to drive in. All in, I'd say there's at least an extra week of joinery work and its cost me in the region of £3k so far, and that was me battening the roof myself, saving £2k. There are other issues. We couldn't install our SVP as couldn't get a tile vent that would fit between the steel channels- but I'm sure we could have found one that worked, just not in the time we had. We had to install a structural bracing "collar ladder" as we slightly exceeded and measly 3.5m max span. Alternative would be purlins, but wasn't an option for us due to head height issues. U value of 0.15 isn't amazing and it wouldn't be easy to add extra to the underside. All of those things take away a lot advantages over a traditional roof, you're not really saving any time or money by not needing to put in insulation and airtightness. And it costs a bit more. That said, if you have a good joiner lined up and the materials, it's still a faster job than a timber roof and once it's done, it's done. No worrying.about finding insulation, somebody to fit it, all that expensive airtightness work. If you are doing a simple roof with no dormers ,valleys etc and the roof will be entirely attic space, then I'd consider it. For anything else, I think it's less attractive.

So, have they ripped the 200mm joists down to 170mm along their entire length?! And at 440mm centres instead of 400mm? I'd be checking with the SE if that's OK... But my gut would be saying it needs to come down and done properly as per the spec. Goes without saying, don't pay any more until it's sorted.

@canalsiderenovation do you still have the low water pressure issue or did it resolve? Low after pressure can be indicative of a bust / leaking pipe....

Nothing helpful to offer, but very common for that type of bitumen / vinyl buildup to have asbestos in it (ours did) - take care and avoid drilling/grinding it etc and wear a mask.

30% is standard on the trade account (got the hard sell today)

I'm more worried about the 1200mm wide wall hung vanity unit... surely it'll need something more substantial?

The cheapest 18mm ply I can get is £40 a sheet, and I'd need 30 sheets! There is no OSB anywhere! Could I use 3x2s within the stud channels and then use 12.5mm OSB (have loads on site) on the face?

@nod how do you fit the ply? Is it within the studs?

So you use 12mm ply then? Do you double board the rest of the wall to bring it out to match the plyed part?

Our stud wall guy has recommend full 18mm ply on bathroom walls for hanging basins, cisterns etc. This does seem the best option, but with four bathrooms and the price of ply still through the roof and no availability of OSB... Can I use 63x43mm timber to frame within the studs? Metal studs are 70mm. We also have a couple gerberit concealed wall hung cisterns which I understand come with their own frames then bolt to the floor. Do they need any additional support? Cheers.

Have you spoken the the supplier or Mitsubishi? I've head they are good for support (one reason why they are so popular)

Would be much simpler just to have a booster pump at the site inlet and do away with the tanks etc. If you only have a ~20m change in elevation, a pump that produces 30m head (3bar) would be enough (assuming effective 0m head at times at the inlet to the site). Individual PRVs can be fitted to units to get pressure below 3bar of needed.

I got a 5pkW system form INTS with GSE trays, solar edge optimisers, inverter and diverter for £4k.

It seems to be highly variable Becca. Definitely order stuff as early as you can, if you have space to save it. You would also be better off going for supply and fit contracts with people where possible... Esp timber, tiles, flooring, doors etc. People in the trade have better knowledge and get preferential treatment from builder's merchants

We got triple glazed Keylights (inc electric operated) within a week. Shop around.. assuming you've not paid in full yet.

Could you insulate between the floor and bottom of the cabinet? E.g 50mm of polystyrene?

I gave up on compact foam and instead just cast a concrete door block. The door fitters hated it and insisted on concrete for the 4.6m bi-folds and massive front door. I'm reducing the cold bridge by fixing aerogel to either side of it.

Knock 'em all down and start again Would love to see the government contract documents for that. But seriously, we do it all the time in utilities. "Condition Assessments" are standard and there is always a point where an asset is no longer worth upkeeping and it's better to demolish and replace with something new. That's because we're looking at 50yr timeframes. I think somebody needs to take the same look at our hosing stock and make the same calls. I doubt any politician would think that far in to the future - short term votes are all that matter to them.