All Activity

It's all about the prevention of backflow from the untamed cold mains > UVC via the hot pipework. If you'd have seen all the installs I have that went horribly wrong, done by clueless / careless / ignorant installers over the years, folk would have a much greater respect for these things. Adding a non return to the hot outlet of an UVC (single check, not a double!) and / or a secondary pressure reducing valve at the stopcock are all retro fit disciplines vs a complete new install, done from scratch; the latter meaning all mixer outlets are fed from balanced feeds. The G3 installation particulars shown in the Benchmark / MI's allows protection for things like mixer taps being changed downstream for 'non-compliant' hardware, which then introduce an issue later on, and more, so you may start with a 2 tap hole sink with separate taps = zero mixing, and then go and buy a monoblock mixer without non return valves supplied in the box, so you don't then fit one on the hot feed to prevent backflow, and then you have caused a serious issue (that you thought was a harmless upgrade). Nobody gives 2 shits about this, not even British Gas. Don't hold your breath looking for anyone to care about you getting roasted, as there are too many plumbers out there (on their mothers side).

Yes, batten the walls leaving gaps for cables, sockets and pipes. You could provide some insulation using plasterboard with eps backing and perhaps more where there are no services, but the void itself has some benefit. Yes the window sills and surround would be deeper but perhaps they could be stepped to avoid a tunnel effect.

To be frank I've done the course and G3 doesn't mention it directly - But with mixer taps you need a balance pressure between hot and cold otherwise the higher pressure wins and you don't get any mixing. G3 limits the pressure to the cylinder to 3 bar(g) via a mandatory PRV. This usually comes in the form of a combination valve which includes a cold take off port for cold water which is also regulated down to 3 bar(g). However if the incoming main has a PRV installed and set to 3 bar(g) or below, the whole house including cold water and hot water cylinder will be at around the same pressure. However if you go this route there is there is a chance of reverse flow so you should install a check valve on the hot water outlet of the cylinder. If you don't have balanced mixer taps, mixer showers, and mixer bath fillers, then no balance feed needed. BUT you do have to include scold prevention measures as no auto regulation of supply temp occurs. The water in an unvented cylinder is classified as wholesome.

Hi all, the summer bypass on our Sentinel kinetic appears to be giving the same inlet temperature as the normal heat-exchange operation. House at 22C, external at 14C and in-flow at vent at 21C in both modes. Has anyone else observed this lack of any temperature drop upon opening the bypass? Ta, D

Just happened across this thread. Traditionally the kitchen cold supply was the only thing that came directly off the rising main to the tank in the loft, other outlets in the house would come from the (unwholesome) tank. When did this all change to requiring a balanced supply per G3? I suppose this is to ensure the same pressures at a kitchen mixer. If you don't have a mixer (like my separate pillar taps!) does it matter?

Thanks. Mix of different floors - there's the original cottage and several extensions. Will share more details as & when. Re service voids: I currently have peeling lining paper on the inside of external walls. Am I correct to understand that instead of stripping & skimming, I can screw in 30-40mm battens, then put plasterboard on top? Assuming no beads injection, leave empty voids or insulate? I lose some room volume, but hide the heating pipes running along that wall & can run electrics along that wall if I want. I guess the windowsills will become 50-60mm deeper, so I'll need to re-frame & I lose a bit of light (window frame becoming more of a tunnel?

Depends what you’re doing, of course. But, we tend to use (for a timber frame build) 3 x sets of bought in sawhorses with sheets of 18 or 25mm ply on top. No vice, maybe the occasional clamp. We’re largely cutting sheets of ply and C24 at this point. Not much use for an mft yet. A tool strongbox for somewhat nickable tools, some wire shelves for non-nickable tools and supplies (these are both undercover now) and a 20ft container for less used tools, fixings etc.

I was wrong, the Forge Steel is the one they stock https://www.screwfix.com/p/forge-steel-adjustable-basin-wrench-1-2-3-4-/410yc, looks about the same size. Now in my hand, it seems robust enough for occasional use. Agreed Monument are long lasting tools, I have a 30 yr old favourite pipe cutter - but now mostly use a pipeslice. No bc after I have reassembled it with a dab of Molyslip it will be easier to service in the future, as opposed to another new one which is bar tight.

Considering the TA we used didn't visit site and won't come to site, that's going to be an interesting conversation.

It will be indeed. I was replying to bancroft about pre-made MFT tops. Plenty of drill bits here, 20mm or otherwise

Erm……it would be you drilling the holes! A 20mm drill bit for £5 and some time marking out is total cost there. Copy other ready made benches, considering their logic for where these holes are and why etc.

It complained about the poor code - which it wrote. It blamed me for the debug patches which it inserted without my knowledge. It wanted to stop for today as it's a mess. We've stripped back the water code completely!. And yes; re did it!. I called it a MoFo a good few times to inspire it . Most typed response by me today "Just do it FFS"

This is what our chippies are using on site, with 2 bits of 4x2 on the brackets, and a sheet of osb. very sturdy. Roughneck sawhorse twinpack. £120 but I've seen them cheaper.

welcome and we look forward to your company over the next couple of years. 1. Living with it. You will be short of at least one room at a time so you need space. Putting stuff into storage gets it out of the way but the cost adds up. A shipping container would cost £1,000 but will have a value at the end. Or it could be your workshop. 2. Plan everything in principle as the priority. Insulation, draughts, heating system eventually. 3. Insulation . a) I'd avoid EWI as it is complicated (too complicated for many installers) and it requires the roof to be extended over the width of it. eps beads is prob a good option and doesn't reduce room size ( and it can be done at any time.. But others are more expert than I. b) loft easy to insulate? If it has any it is likely very thin. This is the easiest place to get a good value increase and before winter. c) what is the floor construction? There's no point in ufh on a draughty or otherwise cold floor. d) making a service void over the walls will make services much easier, and help the insulation a bit. some photos would be good. Not showing the whole property unless you don't mind the world knowing your business. but a bit of wall/ floor/ roof/ loft. Or describe. I wonder if anyone knows of an old textbook on how the bungalows were built? I have some old books (MacKay etc) that provide great info, and came from second hand shops.

Yes, 'tightening' the envelope makes sense, but we cannot comment too much further on the walls (and floors) till we have more details. Are the walls cavity walls? Are they already insulated? If not, while a 'base case' U value of 1.5W/m2K is not quite as bad as a 225mm solid brick wall at 1.7, it is not exciting, when 50mm of insulation can cut heat loss through much of the walls to a third of that.

@tetris Have you checked for ASHP grants in your area?

Thank you. That's good to know and I'm not intending to make the house uninhabitable at any point, so I'm safe. I'll be skint until winter, so no heatpump for a while. Also, I've done some reading on IWI - a completely new topic to me, but I won't be keen on making any non-reversible changes unless necessary. I was thinking more about closing off drafts, installing better windows and improving attic insulation/closing gaps.

Thanks. The Bosch looks like a slightly upsized workmate? Yeah, but the idea of paying somebody £100 to drill a few holes in MDF for me just doesn't resonate. I've heard a lot of good stories about MFT, but personally, I have 10 dog holes in my workbench and I've only used 5 in 15 years I've owned it. One of those 5 was only used 3 or 4 times. Keter looks interesting but on the small side? How would it handle chopping a 2.4m-long 2x4?

Lay the floor flat and level, ramping it up at the door will look like dog shit, you will see it, you will notice it on the skirting around that reveal. 10-12mm step up is absolutely fine at that cill area.

fighting the (expletive deleted)er badly today!

Good suggestion and I have some of that sort elsewhere. There are a couple of locations I want to use inline fans though

Try this then?

Seems best to free the pipe regardless as not sure of the possible stress on the pipe when it is anchored but expands and contracts.

You can actually buy work surfaces already drilled for 20mm dogs - I bought one as a spare for my Festool worktop. Relatively cheap and you can then add whatever legs you want. Alternatively, if you want to really up your game do a Google search for Paulk workbenches. You can get plans for them and make them as big/small/portable as you need.

20260704_155551.mp4