saveasteading

If it was 150 or less then I would use a hole saw. It is easy and a clean and precise cut. But they don't seen to exist above 160, so jigsaw seems to be the way.

Interesting question. They both have plenty of layers so strength the same. Subject to woodworm and rot?...perhaps the softwood will attract British worms more than the tropical wood? But the tropical aspect decides it for me. Another tree down in the Amazon or Madagascar, with a lovely certificate appearing along its trail? Even if genuinely 'sustainable' it increases the demand for such wood. So the better choice is the softwood one, to me. I might give it a swipe of 5in-one wood treatment esp on the cut edges, in case you get plumbing drips at some stage.

I am not one to add unnecessary work, but I would use these clips. You have some doubts about the build quality, so this would be a small insurance, and you can relax on a windy day. And fill the gaps in the PIR.

what is the purpose of the foil? I don't know the product or context.

Are you sure? If ever Ii have to get on steps so my head is near the ceiling, it feels much warmer there. If there is lots of movement and a lowish ceiling, then not so much.

The other factor is that a warm floor provides warm feet and a better comfort level than the air-temperature might suggest. Whereas ducted warm air rises straight to the ceiling. The higher the ceiling the more energy benefit. This will be especially the case in situations such as children playing on the floor, watching telly with the legs stretched out, and bare feet situations. Impossible to evaluate I expect.

I was about to say that any engineered floor needs at least a third layer as a 'balancing' layer to prevent warping. But ply should do that. How many ply, and how thick and which direction of grain is the outer one.? Quite a risk to lay all this and then it warps or splits or shrinks leaving gaps, and you have no guarantee. I suggest you ask the supplier to clarify whether it is, or is not, suitable for UFH. It cant be both. If not confirmed in writing then they must take it back. Or perhaps your Architect will guarantee it.. haha. I once laid herringbone using tiny wooden tiles on a mesh backing. They expanded more than the expansion strip specified, and buckled into mounds. so I re-laid them with even more expansion edge, and then they shrank and there have since been characterful gaps and lips, probably moving with the seasons.

I salvaged the bricks from some old storage heaters. Incredibly heavy for their size, and I am guessing there is a lot of iron in there. Why, you ask? They are in the greenhouse as plant stands as they absorb (a lot of) heat in the day and keep the plants a little bit warmer for a little bit longer. I have come across ironstone in excavations and the weight and heat absorption are similar, although the bricks were clearly manufactured to a precise shape

That is what the manufacturers say. But physics has not changed and energy in = energy out. What has improved is the control system for temperature and time. But it is still using electricity to heat a brick in the night while the price is lower: not really sophisticated at all.

Also, some sounds are more annoying than others. A distant motorway sound just like a waterfall. There will be a big difference in keeping out all traffic noise, as opposed to occasional big lorries/ sirens etc.

I think you have all the comments you need here now. What I would pick from them is. 1. tell them "I have done some homework and am concerned about the sand blinding. Show me something to confirm that your statement is correct, that this is a recommended procedure." 2. dpc, "likewise show me proof of what you think is an acceptable distance from new paving to dpc". 3. stop work and payment until you have done this. Where to find proof? Suppliers of paving products, Marshalls being an obvious one. for block paviours they will show a sand bed, but I think it is unlikely to be appropriate for slabs. However I can't see anything useful from them, but did find this. https://www.paving.org/index.php/how-to-lay-paving-slabs/

I would be more inclined to leave the PIR as it is bought and the hard work done, but then batten out twice to put in a layer of mineral wool, an air gap then a layer of any plasterboard. I don't think it needs acoustic seals as you have created a very long path for airborne sound. The shortcut might be by vibration through the roof via the rafters, so your resilient bar might be a useful insurance to break the contact to the pb. Is the noise high or low pitched, air-borne or including vibration?

I think they told me about £400/m3 plus 30p/m. Also that the logs were usually cut a year previously and kiln drying is then not standard or necessary..

Do it soon as fading starts immediately. At least the south facing as a priority. I would give it a month of dry weather to move and shrink, otherwise there will be some gaps at joints. I'm assuming this is straight from the mill and not kiln dried, and even that shrinks in my experience. I didn't get any suggestion of any discount from that supplier, but their usp is any timber size to order.

Because they are charging what they can, quite reasonably. I went to a small mill and they gave me a m3 price, but fairly said I would get standard timber cheaper at the merchants. JohnMo, that is beautiful. Are you letting it fade to dull grey, or staining it to keep the colour?

Until you have tried to lay stone to a level it sounds easy. The sharp sand is similar cost to the stone and much easier to lay, so saves labour. This will work fine for a number of years then will fail, and when that starts it continues. The guarantee, I guarantee, will be worthless as it will take you £1,000 of legals to get £500 of repair done. Unless thy of course the contractor admits a problem and just does it for you with a smile. be sure that they do proper pointing with wet mortar and don't just brush in a dry mix and assure you this is the best way. If they do this properly it will allow the rain to run off the edge and away, rather than through the sand. It is on a slope isn't it?

Can you ask them to show you any drawing or written spec that confirms their proposal? A lot of people on here will be surprised if they can.

I think the timber price is steady now, perhaps discounts becoming slowly available, and will drop a little more.

No problem: the discussion has grown towards general theory. Ask your supplier how they avoid shrinkage cracks at box-outs. Perhaps it doesn't shrink? Or they add fibre?

Recently Scotland has brought in mandatory, linked smoke alarms for every house, old or new. As most will be retrofit, there will be a very big market for wireless, so it will be interesting to see if the market develops.

It is standard in laying big concrete slabs, but must have a dpm above it. 1. it makes the slab a consistent thickness and therefore controllable 2. it provides a sliding layer for shrinkage 3. it is cheaper than concrete. The problems come when it is much too thick, as it isn't compacted well, and then gets footprints in it which may remain as voids under the dpm and cannot help crack control.

Yes. And tied with wire to the mesh, so that it stays tight to the mesh, and doesn't get displaced or even lost. This is really important to avoid big cracks from a corner to the nearest edge.

Can I ask why this needs waterproofing? Unless it is a basement or has a retaining wall element the only water should be dampness, not running water with any pressure. For dampness, an inner liner might be ok, but it will be forced off with any sort of pressure from outside, in which case the liner should be outside.

OK I do really know about this. Must have specified/supervised for tens of thousands of these, on mostly very big, but some small, columns. Gus and others are mostly right, but my opinions are based on the difference between theory and practice. You perhaps don't need the theory so here is my suggestion. For a small column, as this is, pour the concrete base solid with no bolts, to 20mm below the base plate level. Make sure the Engineer and/or steel fabricator have not already allowed for this with a shorter column. (That would be clever of them but a nuisance if you do it too). Check the column length on site too, as fabricators have been known to cut the measured length then add the plate. Then you can mark the bolt positions absolutely precisely and drill/ stud/ epoxy. (quality important, see the instructions, and supervise the work) For shims use square fence washers, 3mm thick so you are never more than 1mm out. They will squeeze down a bit when the nuts are tightened. OR (my choice) set spare nuts on the stud to the plate level. Then there is nothing in the way of the grout. Grout up using a stiff dryish mortar mix. Use small size ballast if you can get it, otherwise sharp sand. push under and ram it hard to refusal, so you need a back stop board. Flaunch to vertical or 45 degrees. Why not use expanding grout? Because they tend to assume it is magic and leave it well short of the plate and with gaps in it. Use it if you like but still supervise.

Yes be concerned. I think this is just easier to lay flat than stone. It can't really be rolled or whacked hard either. The problem I see is of rain running through the joints (perhaps in 2 to 3 years, and washing away the sand. As suggested above, if it has enough cement in it then it will be ok. but I think this is just to suit themselves as it is difficult to impossible to lay stone exactly within a few mm..