saveasteading

Good points. I will think further. I assume I wasn't sharpening the CsS properly: I had a simple round file, and thought I was following the instructions, but perhaps not. Thinking further, the hours of use for these won't be high so cheapo tools may suffice. And the tangled bushes will eventually behave better and the trusty bow saw and pruning saw will be usable again.

Let's go back a stage before throwing money at fashionable tech. Where is the humidity coming from? Is it just wet rooms and breathing? If so then extractor fans as above is the simple first step. But could there be dampness problems through the fabric?

yup. There will be a fair bit of heat wasted to the high vaulted spaces, and some biggish glazing. but otherwise it's normal. If the heat pump/s end up turning off more than expected then we can live with that. We are fortunate in having a known, proven big-time plumber who is advising foc first, then we are prob working cost plus. and I think we will buy the materials... again a favour and based on trust... Not that they will be cheap, but it is far too big for a smaller outfit anyway. The reason I am asking you, dear BH posters, is the overview, beyond the simple sums. eg noise and airflow. how lumpy a cable to get through the house. and the unknown unknowns.

Don't worry on that score. It's effectively a new building. The floor insulation was delivered yesterday. 4 lorry loads for 300mm th. No , my over-whimsical comment is that behaviour change is all we could do. Or add MVHR which we have decided not to after due consideration of cost/benefit. I'd have to move chairs to check but I think we were looking at 7 +5 kW and now 1 x 11kW. There seem to be lots.

Teach people to shut doors, and not wash dishes under a hot tap.

We've been assuming 2 x heat pumps because there will be two distinct zones. It's too big for one unit on single phase. But it is all one family building and we have 3 phase power available, already into the premises. I'm aware of the principles of 3 phase efficiency on motors, so presumably this will be preferable. Maybe also not require additional internal distribution pumps. But are there any downsides? The only one I foresee is family arguments over dividing the bill. Any technical issues?

I agree totally with @jack. For some things that will work, eg we are buying all the materials for our timber construction. But we have an established relationship with the chippies. So we are on the same wavelength re waste and progress. It can get very messy if the workers are prioritising speed over efficient material use. You get annoyed about buying more timber and fixings and the amount in the skip. They get annoyed that they are short of something you haven't supplied. What if the BCO says they need something more? You buying? Groundworks.. you think they have dug too deep. Who pays for the extra concrete? That would be much worse for plumbing/electrics. Where you might do it is for a very small trader with cash issues. You buy the big ticket stuff on demand and leave him the hassles. Remember that you will be responsible for it turning up on time and being suitable and for dealing with faults, or have to pay their downtime. Don't dabble.

I am currently contemplating whether to go for a sabre or a small chain saw or a single hand chainsaw. I've never had a sabre saw. But have a dead chainsaw for lack of use. Why haven't I used it much? I found sharpening to be difficult, and it isn't any good for small works. Plus some fear... certainly not for use up a ladder. So continue this discussion please. Tell me which. I'm confused by how many options there are for battery chainsaws. It would get most use in gardening (heavy pruning) plus chopping pallets. And generally in joinery. @Nickfromwalessays sabre. @G and Jsays handheld chainsaw. any more votes?

You called? I have only skim read. But I don't see a mention of multiple small fixings... that would apply to a lightweight hanger nailed to a wall plate though. This happens to be my preference I think. A timber the same depth or greater than the joist will bolt to the wall without stressing it to much. The deeper it is, the more robust it will all be, and easy. As above you must watch the builder very closely. Dont drill too big a hole... the bolt should just fit without force. Threaded rods are usually thinner than stated. Grind the hole, don't sds it. Brush out all dust. Look at the resin mixing and discard it until it is uniform colour. Turn the bolt as if slowly screwing into the hole this gets the resin fully into the thread. And continue til resin is screwed out of the surface. This also picks up remaining dust. Don't touch it until it is hard. Use washer and tighten the nut until the wood just distorts. Then you use 80p hangers and lots of nails. OR use heavy duty hangers fixed into the mortar coursing.

Indeed. Often the advantage of the account is simply the credit, which a small business may rely on between clients paying. But prices are variable. Eg blackjack recently. 10 litres varied from £18 to £35. The best prices were wickes and our local BM even at shelf prices. Trade discount at TP is 10% off, but still probably high. Online wasn't cheap. SF and TS also seem to be ever dearer.. they depend on necessity and convenience, and selling lots of small amounts. Nothing wrong with using B&Q or Wickes if they are near. I once got a whole lorry of blocks from TP then was surprised when B &Q lorry turned up. For larger purchases you should try to get your address or the project reference on your receipt...it will make thd claim easier. Also I suggest you staple any till receipts to an A4 along with a note of what it is for. I know if I was the vat assessor I'd welcome that.

It's not going to fall over. Water will run through the gaps so you might want to put a drain along the base, as long as it has somewhere to run to. I

I'd never read up on this so has been interesting. One of the sellers had good info on use class. Light domestic, light office, heavy commercial, including how much water it could hold! 6 litres/m2 is a lot. Thicknesses not so easy. It's potentially tricky and messy to retrofit so needs thinking through.

Of course. But any time you open the door most heat will shoot out so I can't see the point. And the surface area compared to volume also provides a poor figure. Spending a fortune on sustainability for a building that is far from sustainable through the material/carbon content doesn't make sense. A shepherd would not do that.

That's quite good. More important is local variations. The industry way is remarkably and sensibly lo-tech, with a 3m straight-edge. Any completely straight timber will do. Lay it down (not levelled) and measure any gap whether at ends or middle. Then lean on the ends and rock it, and repeat. Any and all directions. 3mm or less is a pass and a few scattered failures may be OK too. I bet your floor passes.

Does that work for sand and cement? For a large area I'd use our cement mixer, but it's dreadful for getting loads stuck to the rear and the paddles.

This discussion prompted a lunchtime discussion.... so has been very timely. So it's decided to have a recessed matwell to the front door. We will box around an area on top of the pir so that ufh doesn't wander over. Then screed leaving a void. Them bring up to the necessary level in latex, then form a well with angle. And to sliding doors, just an over-mat that can be removed when we want the brochure look for the floor tiling.

AS mentioned above... clearance is a big deal. I've got 2 doors where mats sit too high and the door hit them. Not my mistake obv.. it was a concrete and lino floor and just putting tiles down caused a clash. Next time I woul cut out matwell. Thinks.... don't put ufh pipes right at the doors.

My concern on SIPS is my own ignorance. That to a large extent is because they don't seem to aim at the professional contractor market... which to me suggests that it isn't commercially competitive. I see the systems used in Architect led projects where the end result seems very expensive to me... so I (cynically?) suspect that they do target the public at self build exhibitions, and some architects who are , unlike designer-contractors, not so aware of the real cost. Hence quotes I have seen on here and elsewhere will exclude steels that may be needed, interfaces, perhaps even insulation targets. Thus beware. absolutely. To know how it works out in real life the pros on here need to know more. The self builders who have used sips may well be very happy with the results, but have probably not got experience of other ways. But they will advise of what, if anything, to beware of. My gut feeling suggestion is to you, as a self builder who wants lots of hands on and economy , is 'stick build'. It fits, and is sympathetic to newbies*... it offers second chances. But you won't see that at exhibitions. * that would include theoretical me if without builder help. Strip footings, stud build, timber cladding, timber roof, metal sloping roofing, or tiles.

That to me is decent justification. A kit reduces risk for the beginner, just don't try to change anything from a proven form. It depends on more than that though. Geometry, the ground and topography, how it links to the existing...and more.

Tell more?

On reflection I'm not thinking to add redundancy thtough extra piping, but to avoid petty savings. Eg does the utility room need any ufh? Miss it out, or half of it and save £30? Space the pipes further apart in some rooms? Likewise. There are places to save hundreds or thousands or tens of thousands and this isn't one of them.

Measured by bucket or bag, not by shovel until you have a total feel for how much a shovel holds. If you shovel the mix to different spots there is less brushing. It's not hitech but very important so that blocks are locked really solidly.

with a fan drawing air from the adjacent areas every time it is used.

I agree with @ProDave that bolts are advisable, not expensive either. But it might be tricky to drill unless you have a 90° drill. ring shanked nails or fully threaded screws at 150 cc, staggered.

I'm no expert but we are having a big area designed at present. There are additional pumps at manifolds.