Carrerahill

We used PIR, fully sheets with foamed and taped joints. Bricklayer put the internal walls up to a level first, then left all the wall ties sticking out, I worked out I could just push a full 4x8 sheet of 50mm PIR over the ties and they just poked through, I added the retention discs and could install about 8 sheets in 30-40minutes, it was comical how fast it went on, we got a really tight fit, jointed and taped it all and it looked like a perfect foil box. If I was doing it again, I would probably use 75mm PIR, I would even look into stretching it to 100mm PIR, but it makes the walls thick at 350mm, but then, not really that much worse than a TF and block build using block 100mm, cavity 50mm, and 150/175mm TF. So only 25/50mm in it.

If you have a gap, then yes you should close it up to get a better fit and seal, is this internal? Depending on how it all looks and will sit I would probably fit a length of say 19*150 onto counter battens/packers to get the desired 30mm. My reasoning for this may be driven by potential for condensation sitting on the steel and rotting out the timber, but it depends on the make up of this, what is the room type, what is the insulation, but I would be reluctant to come up hard against the steel in one single piece without considering potential issues. For fixing I would probably just pilot drill and stick some stainless self tappers in. Shot fire would be good but I am going to guess you may not have access to one.

Which ones in particular? I am seeing hits for 250 for £50-140 depending on which version. https://www.lbsbmonline.co.uk/wall-ties-st1-250mm-box-of-250-cavity-tie?gclid=Cj0KCQjw0tKiBhC6ARIsAAOXutlDxpMHy2J9v06nG3-jtf1gikFb0u_h_IPVr7-w1Gpxl6sYTsn5N5saAvSiEALw_wcB

Lazy (expletive deleted).

Agreed. A plausible reason for what is happening here is that they went down the G99 with export limitation route, got lazy and just shoved in a G98 which frankly anyone can do with their eyes shut and it is not onerous.

Essentially this may be your bottleneck, you see the DNO doesn't even want the inverter to be capable of anything over 16A on a G98 - however, G99 with export limitation would permit this but you then need to fill out the export limitation details to prove you won't blast more than 16A into the system. Once we see the mfr. & model no. of the inverter you have things will start to slow into place. Even a photo of your PV system showing the units would be good - a clear photo will maybe show what is connected to what and how.

You! Get your crayons out and do a wee scribble for us, where the bits of string go into boxes and things...

We need a system schematic with model numbers of devices and we will have this sorted by sundown.

Reading the conversation between you both was both entertaining and slightly perplexing. Typically you have your PV generation, that comes down into an inverter, or lets just call it a device, because it might be a charge controller, but anyway, that "setup" you would expect would charge the batteries, and or run the house and or export. You are clearly limited on the export limit 16A rule, but that should only impact export, you should still be able to pull more and if that load dropped off it would then clip the excess to keep your export down (in truth it will spike for a fraction of a second when the load comes off, but it works it all out rather fast. So, perhaps your limiting factor is your inverter section of your setup. Maybe it is only a 3.6kW or something? I wonder if the PV installer went under the G98 rules which limit inverter size not thinking about G99 with export limitation and that is now a bottleneck?

For your paint, I would empty it, clean it out, brush/vaccum it down and then just blast on a sealer/paint type thing. I did the inside of my shed with a concrete and wood sealer, it looks and smells like white-spirit, I just blasted that on. As for the foaming, take care here, you don't want to seal it all up then start dampness/mould because there is no air movement. Foam is good for some things but often misused and really is the devil. I don't know the full details of your building but just think it all through before you potentially cause issues. I might be more tempted by a mesh and staple gun to insect proof the place.

Will the new garage be connected to the house? If it is, I would make the case to retain the existing founds based on the fact they are tied into the house and will therefore provide a better connection at found level. New founds can cause issues with differential settlement, if you dig them up and pour new ones, which are for example, much deeper or bigger, then that part of the building will start to behave differently to the rest and that can often lead to issues.

What sort of system is it? With any luck the system has not been fired up yet and could be commissioned by anyone with the savvy. If it is a Texecom or something similar you could do it yourself with the manual. Probably just needs firing up, battery connecting etc. you would need to know the cable designations for the zones and what they do but even that could be worked out by a competent spark or DIYer.

Take photos with a measuring tape in place to show bearing length and email over. Depends who made the mistake the if TG engineer and the installer both work for the same company you might find, unsurprisingly, it will be "fine". The steels should really have been ordered from site measurements to solve issues like this, or an absolute guarantee the build would be done to correct dims and this imposed onto the builder, but even then, things slip. Options may exist to rectify, in fact I am sure they do, but you need to get this looked at properly now.

I can see the benefits of this in the winter, but it seems quite a mismatch at about 66% over, typically PV oversizing is usually about 20% - this is not an industry standard but a common figure quoted in the industry. I would expect on a good sunny day you will be clipping a lot (lots of heat in the inverter - not good for it) and wasting a load of generated power. I think I would be upgrading your inverter to about an 8kW unit - get one with a reasonably low start voltage and you won't lose out on much on a grey day.

Things to consider here are how are you going to finish the blocks, if you plan to render them you will need to consider the constant dampness that will come from the inside of the planter, through the block and damage the render, if you use facing brick it could be the same, so you need to consider how you will build them and put in an isolation layer for moisture. Blocks are blocks, you do get facing blocks but you probably want to be looking at facing bricks. For construction ideas consider some methods used in the waterproofing of retaining walls. A Geo-drain type membrane might help you here.

For common sizes in regular use I usually buy DeWalt SDS bits. I have however bought some of the Toolstation TookPak (I think they are called) super naff 22mm SDS etc. for boring 5-6 holes for conduit and pipe sleeves, did the job, cost less than £15 quid and are still on the shelf for the next time I need to drill a hole that big. However, my DeWalt SDS drills have seen me through renovation work, an extension, a garage and now building work at my parents house. Those are your common 5.5, 7, 8 and 10mm set which pretty much cover every fixing. I also bought a 16mm bit for doing the resin anchors, it was an Ebauer, its done about 60 holes now and still works well. I am running all of these on a corded Bosch SDS.

How would that work?

In that case, I would call the grinding man first (try tree surgeons etc.), he has done this 1000 times before, tell him what you want to achieve and he will advise, he might want you to dig down a bit either side so he can get right in, ours was fully exposed when our guy came and he just chewed through it all by steering the tracked grinder at it with a big spinning, highly lethal looking cutting head. You can hire them too, but probably more hassle (and that is coming from me who DIY's everything).

The first thing I would look at and consider is the existing building, make up, materials and how long has it been there. Assuming it has been there a while, is there any damage or cracking, subsidence etc. etc. that is caused by the existing foundations failing in some way? I would give the foundations a bash with a hammer and a cold chisel to see how hard the concrete seems, I would expose sections of the foundations and check for big cracks, bits that have fallen off etc. If the existing foundations are suitable in size, and pass all the other common sense checks above, then I would consider the new structure weight. How does it compare to the existing, if the walls are basically the same as before, with only a pitched roof going on, I would not be too concerned as the new roof load is supported round the whole build. Assuming you are pretty sure the founds are OK, and if not, even get an SE to come and have a look (dig some test pits and let them have a look), then I would probably just crack on and do it. Do you actually have building control on your garage or just planning? If the garage is small enough then BC won't be involved in which case do your checks above and carry on. If BC are actually involved, then it depends on your inspection schedule with BC. If they want to see the trench and founds then you need to raise it, if they don't really care as it's just a garage then on you go.

You basically, you dig you trench, then get a stump grinder in to basically grind a route through the stump and all root systems etc. it more or less leaves a channel through the stump, below the root ball will be soil again, dig that out, you have a trench through the old stump position. We were then left with a trench that was a bit wider in the middle, so we used timber to create some form work to keep the foundation the same width the whole way along. We now have a 1000mm foundation the whole way down, even though the stump area was maybe 1400mm wide.

Can't you remove any obstructions between two joists, then drop the pipe down parallel to the joists then rotate it under the joists? It is not clear from the photo what the full situation looks like but from the area I can see it looks like there is a good space below the joists. I would also be willing to reconfigure, temporarily remove things just to get this pipe in properly. I'd not really want a jigsaw soil pipe, although I am sure it could be done. Could you not even get 1m pieces down and then rotate? Another thing to consider, is there any outside wall access that you could core a hole to feed the pipe in? I have seen that done before.

We had an issue like this last summer, an old Cherry tree stump right in the middle of a proposed wall, tree had been down for 5-6 years, I was sure it wouldn't move, but thought it might break up, so tried with a narrow bucket on a 1.5T digger and the stump just laughed at me, we did not want to dig it out as it was going to screw up an awful lot either side, so we got a stump grinder man in, he ground out a channel through the whole stump and root system at that point, and then we dug down to the same level as the rest of the trench before/after it. The foundation was wide as it was but we cut the channel wider at the point of the stump so the roots were back enough, then placed formwork to keep the concrete from widening out too much. A year later and soil and stone and bits have back filled the gap and roots randomly jut out the ground either side of the foundation but about 300mm back from where any wall will be, by the time this gets back filled with stone the roots will just rot away and be sequestered into the soil being no different to a root in a garden near a wall being left to rot. My initial plan was actually to burn it out, build a little bonfire either side and over the stump and set it on fire, I was game, neighbour was not so keen.

This is not over the 68mm - I reckon this runs deeper, the names tell me something about the two couples and I fear this is an abject lesson in multi-culturalism.

Yes. So basically you clear a bigger area for a safe build, pour a box, backfill. I follow a lot of North American You Tubers who self build, or trades who film their work and spent 2 weeks in Vancouver where I watched developers at a local site over the 2 week period and this is, 80% of the time how they do it, you would need to have the space to do it like this though. If I had space I would do this as I feel it is a safer option and easier all round, only issue would be muck-away but depends on your situation that might not be an issue at all.

Ah, see if you are a developer, they will sometimes even pay you to install it! I put in an application for 96 apartments earlier this year, they offered £116 per apartment to the developer to install it all - they then come out and hook up the main fibre to site. They even free issue duct and fibre. It is actually very clever if a bit cheeky, you install their network and they then know they will almost certainly get line rental from BT or another for the next however many decades!