saveasteading

I refer you to the remarks I have made before re the knowledge of the BRE folk who designed and control the program.

For an occasionally used workshop I would consider a Mediterranean type Aircon unit. A fan and heat exchanger outside and fan inside. They used to be very poor for heating, but now appear to get a 4x energy rating. For £500. Plus an infra-red work-bench facing heater for instant warming of you. There is a good big one with optional stand at toolstation. They all show a bit of visible light now. for unbelievers and to remind us to turn it off.

Could you explain further please? A short strap inwards onto the stone jambs is ok because we will fit a timber plate into the junction. But we want to leave the stone exposed as much as possible. Pleased to say that the bco has accepted the stone being exposed internally, locally as long as we trade off with more insulation elsewhere.

You have been doing it more recently than me then. Never done it (ie supervising from above) other than manually. What else has improved? How do you pack up the last few mm to prevent a tiny gap and further settlement? How long is each section and do you prop it or cross fingers? In a tight space revert to hand dig?

I am very interested but sceptical. I would need to see detailed designs and justification for the loadbearing capacity, and why frost heave won't affect it, being so shallow. Most commercial buildings have huge point loads. I guess it is that i have investigated so many ' amazing new ideas' that makes me sceptical. Screw piles for one, were said by the suppliers to support factory columns, but couldn't. Expanding foam, as in a concurrent discussion has its place, but limited. So don't let me stop you, but report as you go please.

I have in my head £350/m for underpinning, but that was a while ago. A horrible and slow job, done in small sections, using shovels, tunneling under the foundations.

That is why Estimator is a particular skill.

Sitting it on some aggregate does nof seem adequate, other than for a temporary or lightweight building. Garden shed yes, garage no. And you don't need insulation under the slab for these purposes....why not use local stone?

It is expanding foam. It expands under the slab, and forces its way into gaps and cracks, and also forces the subsided slab upwards. It does not resolve an underlying problem. Underpinning extends the foundations downwards, into deeper ground that is stronger and less influenced by weather and trees. Two different things. I would consider the foam if there was an obvious reason for subsidy other than foundation failure...eg in a warehouse if 3 tonnes of steel had been dropped. A guarantee from the installer would be interesting to see, if they have offered it.

Interesting stuff. Made from waste bottles. Stone that insulates. No pir, no footings. What's not to like? £130/m3 is a lot of course. But how thick to insulate to standards and support the structure?

So the vendor's insurers are aware, and have commissioned a survey which says that the foundations have failed, but are not paying to repair it, and it us up for sale. Hmmmm. Any more info on this? Would you get any insurance that was worth having? Mortgage, probably declined too.

Firstly, i am both Engineer and contractor. For a clientI I take few risks. For my own, and family, i take more chances. We have taken on severely distressed buildings 5 times, always to live in. In every case there have been nasty surprises, even to me. These would nof have come up in reports other than as general warnings. More accurately these are considered decisions, not risks. So the default here is to say to be careful. The discount may not begin to cover the risks....but i don't know as i don't know enough about this property. If this house was possibly to be mine i would cost the repairs of the known problems, but also allow for the unknowns. Repairing to live in rather than sell is an advantage. Things like the drains can be dealt with as and when. A builder either has to get it right, or disguise the problems, in order to sell it. Stitching is a repair, not a solution. Best have an expert look at what caused these cracks and the floor movement. A good local SE could simply have a walk round inspection and give off the recird advice. This works for easily seen problems and avoids unnecessary detail and report cost. For example i once suggested this, on the basis that the SE would say only whether the house would get a mortgage, and why not. Client paid for 2 hours and avoided an expensive mistake. The discount may not be remotely enough. Be prepared to let it go. On a positive. Maybe the ground is ok and thd floor is just very badly made, and can be repaired. Maybe the walls are cracked for other ressons thsn foundations, and just need repair. On a negative....often houses are beyond repair, demolished and rebuilt as new. Be careful, get independent professional advice.

Gus is right of course. You have to be very determined and stroppy or you get the brush-off, esp ftom the big developers. Not every crack and creak is a major problem. The brush-off can move from politely ignoring, to bullying. The big developers' Architects and Engineers may be very good, but are usually selected on lowest price, and without an overall responsibility. There are well documented cases of very serious design faults being denied....their reputation strangely not being their main concern. It seems though that your issues may not be so serious. Photos?

Hence factors of safety. Some for load, material, and build quality. And a lot of that weight is at the edges. Then, most structures are governed by deflection limits...ie they flex and feel uncomfortable long before they break. I assume that the stairs did not fail in this instance.

We recently got thd best prices from the local builders' merchant. Use the online sellers for the initial guide costs but beware delivery cost. Never ignore wickes and b&q...always worth a quick check.

Welcome. Always something to learn, and there is a lot of knowledge and wisdom in here.

I don't begin to agree on this broad statement. In clay and rock, gsh is not efficient because thd heat is not replaced. In fact, boreholes freeze. In porous ground it can work, but with great capital expense and too many disappoinments. I have been going to gshp industry presentations for decades and noted how the wild promises were gradually altered to suit reality. Without grants the true value became apparent. It is now acknowledged that most boreholes need to be reheated in summer (pump running) So it is really air source or solar, with the ground evening out the seasons. Slinky coils take solar energy from higher ground and can be OK in large sunny spots, but they also chill out in cold weather. I know this from observing failed projects in SE clay and the industry recently acknowledging it. You have inspired me to look at the EST website. They show better savings from gs than as, but at much higher capital cost. But they are very quiet on ground conditions. Air source works well, and reliably, except in very, very cold conditions. Convince me otherwise please.

No. They don't work efficiently in most uk situations. No hot rock.

Please excuse if I have missed something but my thoughts are.. The cross sections are a bit vague. Where is the floor insulation/dpm? Why an extra block to support the beams, is the outer wall existing? Yes there is a cold bridge..this can be sorted but needs more detail. 2m deep footings. Presumably there are trees about 10m away , at all sides. Ask the local concrete company what their cheapest mix is. Leanmix is fine, but I would just ask in case they have a mix with bigger stones, or single sized, etc that might save a lot. I don't follow what the line under the beams denotes. It looks like a slab but it perhaps is ground....it should say on the drawing. 700 and 900 seem very wide trenches. Others tell please...Scottish regs used to require a solum ( stone or something) below a suspended floor. Does that apply?

That was what I meant. Reclosing the gap. Window going in soon so i will report back.

Indeed. I have seen buildings which should have a poor rating, get a good one. Ignorance, lazyness, lack of effort worthy of a tiny fee, or writing the rating the client wanted? Probably all the above occur. The algorithm is flawed in the first place anyway, but of use in comparisons if completed professionally ( i mean honestly and thoroughly) I don't think designing a heat system to suit a SAP is the best idea. The Jeremy table is probably better.

Thanks Miek and to everyone else who didn't respond. No I am not being facetious. One of the great things about this forum is that people don't guess, and don't reply to say they don't know...which I just hate on other forums. I have had great advice that I have acted on, some that i have absorbed and then not acted upon, and the occasional silence. The latter is always on complex or very particular circumstances. Silence confirms that my ideas are as good as anybodys..... probably, and is all my own problem. So the decision is made, and is to not use mechanical fixings up to the arch. Fixing will be by quality expanding foam. We will probably first insert expanding foam tape to the outer edge as a permanent and flexible weather seal. For general intrest, the bulk of the units are Nordan: timber windows with aluminium outer skins. They couldn't handle angles or curves*, and are a bit clunky at multiple units, so these are coming from Stevenswood. Upvc with a coloured outer skin, and so very much cheaper. * a series of straights....3d bit style......not seen yet.

Does it expand after curing though if, as arches do, one stone moves up a fraction in a year or so?

We have some characterful stone arches. Another way of saying wonky...they have moved over the years and are not symmetrical. That is the glory of arches, they move, adopt a new shape, and keep working. So our new windows are asymmetrical too. They are upvc frames, made with 4 different straights at the top to replicate the curve at a fraction of the curved cost. To the sides and bottom we will plug and screw. But I am conscious that the arch may move again. How to fix to the top? If screwed through then any joggling of the stone and the screws will push or pull at the frame and will likely crack the glass. Or thd screws inhibit the movement of the stones. Perhaps just expanding foam as glue, and no screws. How flexible is it? I suspect it crushes but doesn't expand. Or memory foam strip? My inclination is to make slip brackets of 2 angles with a slotted connection, then fill with quality expanding foam and/or memory foam. There should be 20mm top gap at the joints, and wider between (straights under curve).

That smell is in my brain while I read your comments. I had this at a wc connector. It was a sealed joint and extra mastic so I didn't suspect it for ages, but eventually noticed a tiny gap almost out of sight. New plumbers mait all round and thoroughly packed: sorted.