saveasteading

If the house is small and rectangular, with A frame (or attic) roof construction. then there is a Scottish Government document outlining the whole design process. As a Chartered Engineer I still found it slightly challenging, to follow the process, but it is all from tables and not first principles. The purpose of it is to allow design by a 'competent' and experienced person, not necessarily qualified. Foundations too.

I only know about SE England on this but it is still Openreach so probably the same applies. There were all the statements about 98%, or whatever, of the nation getting broadband. That 2% includes everyone in a small village or below. Then there were the £3k grants, but that covered about 10m of fibre, and it needed an awful lot of neighbours to combine to anything useful. That is, unless your area is getting lots of new housing, in which case they will get broadband and maybe, just maybe, it can be latched onto. Copper connections can get you 40MBPS IF there is fibre to a box nearby. Otherwise it is likely to be 4G I have heard many stories of Openreach salespeople offering high speeds which are far from available, so the moral is to sign nothing until clarified. In my village we got broadband by commissioning a small company. They used radio signals between church towers*, then linked to the existing boxes, and copper after that. Cost £50k about 15 years ago, but was a massive improvement , and nobody can compete yet, unless in new housing with fibre. * they intended to take a poorish but decent signal up to the tower then beam it to the countryside areas, but when up there realised they could see 4 other churches, and changed their plan to 'import' signal tower to tower.

I vaguely remember it being a few metres, but could well be wrong. Whether that was for a safe working distance (which must be sensible) or something to do with electricles I don't know either.

You therefore need both the density of the plasterboard and the softness of the insulation, and had best use mineral wool. Outside structure brick? Remember that sound escapes through small weaknesses in the structure. for example through windows and doors. Don't forget the ceiling. A nice hard and rectangular surface internally will increase the internal reverberation noise and so may persuade you to keep your sound levels down

What acoustic property are you seeking? Noise in or out of the new space? Or reverberation within? What sort of noise?

Not just buying power, but familiarity with the material. Steel does mix with timber, but you can't just shave a bit off, bang a few nails in 'for now' or adjust. Then there are pad-stones and possibly bolted joints for the steel, so the joiner may want to get a general builder in. In summary I love steel but like timber buildings to be made of timber. This especially the case if there are hips or valleys....steel is horrible for this, as it is not forgiving. As Gus says 'then you iterate'. Never forget to go back to the original issue and check it hasn't gone off track....this is worth a lot of money and quality. Well said Gus. An Engineer (or other professional) who iterates and thinks of the client's needs.

We took to doing it as standard in some new school buildings. Always offered to the client as an option, which some welcomed and some declined. It wasn't really for vandalism, just big teenagers jostling and the urge of kids to excavate into any small hole that has begun to form. For my own home? I wouldn't bother.

I imagine that it could badly affect the house value. There are enough people with misguided fears about the effect of pylons, wind farms, G4 signal etc, that some would be put off, and you generally need multiple interest in a property to get the best price. So the value could be tens of thousands on top of your own living with it and disruption. £50k?

To expand on SBMS message. Surveyors use GEA and GIA. GIA is the usable space inside so it doesn't matter how thick the external walls are. However it includes all internal walls (ie they are not deducted.) The reason is that people buy, but especially rent, by the m2. (But surveyors being surveyors, it is usually still in ft2 because it sounds more, and the rent sounds less. 10.76 is forever at hand for conversion in discussion) GEA is the actual building area from outside of walls. It ignores overhangs. This is what builders use, and is more realistic for build cost. By the way, beware scaffolders' cost per m2 face of scaffolding. They tend to measure the ' as built' scaffolding from corner to corner, so the corners are included twice.

Pity the professional estimator, who does it all day, every day, and gets criticised for winning a job too cheap, or for losing the work. I was that man.

Thanks all. Confirming what I knew really. This is conservative for a 6m span timber building with no upper floor and a central prop. Especially as it requires us to dig out the strong sand base and replace with type 1. Bottom slab is shown as 125 thick with 2 layers A252 Edge beam 2no layers of B1131 and pairs of 12mm links at 300cc.

Thanks, just checking terminology, as 'raft' to me is a thickish slab with 2 layers of heavy reinforcement. Yes, tying the UFH down to mesh is a bonus....once had a plumber insist on pouring his own screed and it got under the PIR which floated.

Who chose the contractors to ask? They may be all of a type, and selected because life is easy for the architect with them. Sometimes you get remarkably different quotes from companies with different specialities/ overheads/ attitude to profit. When I was an estimator, for a predesigned project with bills of quantities, there could easily be 6 quotes all within 5% , and only 1/2% between first and second. Whereas in 'design and build' where the contractor who has design and commercial skills (or not) the variation is more typically 30%, for the same quality but different approaches.

Make packers from glued together bits of hardiebacker?

By 'passive raft', does this mean a slab to the passive house principles? ie not a structural raft which is supporting the superstructure. I say this as the slabs in the pictures appear to be fairly slender, and have crack-control mesh, not structural.

No, of course not, but it is not concrete either. Very impressive, and a benefit of the package process of joined-up thinking. What purpose do you think the bottom concrete has, other than tidyness?

When questioned on the heavy construction we (not me unfortunately) were told uplift, down force, thrust.....all of which exist but i think are overestimated here. We will be asking for the calcs, and i will get the red pen warmed up. Most glaringly is....remove 150mm of natural sand and replace with 150 type 1.....then put PIR on it before screed. Perhaps type 1 is the default and no further thought is given. I'd most like to see either a standard drawing of a kit timber building onto a conventional edge footing, or photos of same.

Sitting on polystyrene. Excellent. And it hasn't sunk into the ground or blown away yet? We have that sand as natural ground but the engineer wants us to dig it out and replace with type 1, then doubly reinforced slab, then insulation then screed. I might suggest that the extra cost comes off their bill, which will mean that they owe us.

Neither do I. It ends up at the sewage works, or in some ditch, or blocking your soakaway. I like an open ended rwp with a grille on the gully, then it is very easy to clear. Also you can spot if the flow is reduced and clean the gutters in good time. And, for muck that can get down the rwp, it is much easier to clear at ground level than having a leaf trap in the gutter. No need for a trap unless it leads to a shared sewer. Straight into an elbow and to the drain gets rid of your detritus, but you will need a rodding point....might as well have a gap and grille. If you have elbows and no traps that is fine....again ..unless they join a foul drain, and if you ever need to clear them.

I spot people with recent knowledge of foundations. Our Engineer has designed something I think is suitable for forklifts. Any of you with timber frame able to copy or describe what you did for footings and floor slab? ground bearing slab or raft? footings connected or separate? how much reinforcement? sub-base/concrete /insulation / screed or simply sub-base /insulation/ concrete? Steel straps to hold the building down? That sort of thing.

A lot of joss sticks, and you couldn't open a window.

I have had screws that were supplied with shower fittings, that have corroded, and it can make a horrible mess as well as it will fail at some stage, so I don't trust screws unless a trusted brand and clearly stated as rust-proof. For recent fixing of grab-rails I even bought stainless steel to be sure. You don't have any risk of dampness by the sound of it, so that isn't an issue, but I would either countersink or get a self-countersink type. I would select hardie-backer again, but the only issue was cutting. Scoring it like plasterboard, but on both sides, went through a lot of blades and still left a hairy, roughish edge. Apparently there is an official cutter available. If others have had success with saws etc, then take their advice.

To expand the same subject, we have 2 ashlar concrete lintels which have cracks. they are in line with the outer skin of masonry only, with the remainder supported by very hefty oak lintels. My proposal was to jack the stone up the 1mm or so it has displaced, then drill through the oak into the granite and bolt them together (no rubble). The Engineer's proposal is to drill up through the crack and bolt it back together. Again I am reluctant but not so much so.....if it works. We have found a good mason, so he might have experience or views...he hasn't seen this......but there are more of you and with a variety of experience. Any thoughts?

Serious practical advice there, thanks. I might invite the specifier or his boss to do the first fixing: show me how it is done. The core at that point might have a nice big stone that can't be drilled because it displaces, or be all mortar and bits. There are so many other unknowns though, such as what does the back of that outer stone look like. With some serious tape measuring we can assess that there is a substantial stone there, so that we are not too near an edge. But we can have no idea what depth or contour it will have. Indeed will it be intact or perhaps cracked. Will it be thick enough to take a 50mm hole without punching through the outer face, or pushing the stone out. In any case I don't think it is good building practice. . Where there is any sign of movement we may be shifting the stresses somewhere worse. Where the risband joint shows no distress we are encouraging stresses, and the wall is not built as a structural wall, simply as a divider...If there was no wall there, there wouldn't be an imagined issue. If we are to do this, I would have no issue with simply fixing to a selected big inner stone. The bond created because of the 3 layers is surprisingly strong, to the extent that one area of local collapse by damage, still has an overhang of rubble wall. There are far bigger issues with the design we have received, but this is one hurdle before dealing with the others.

It is tough, resists the screw head and pulls tight. I used the official screws as it was for a shower and i didn't want any corrosion.