Search results

Hi, I need to add 2 inspection chambers to my drains because of new connections. One is a new stack which I will probably run at 45 deg to existing drain for better flow and so I don't have 2 manholes almost next to each other. The other is an outlet from a downstairs bath room that turns 90...

Plaster is ~0.45 W/mK thermal conductivity celcon aerate concrete blocks are 0.15 W/mK so a lot lower conductivity, below the 0.5 W/mK required (and so is plaster but I guess that is near enough to be ok).

It won't be 102 because that says "with the cable touching the inner wall surface" i.e. back of the plasterboard. I did consider dabbing them it but method C say only applies to wall < 2km/W (>0.5 W/mK) and celcons are 0.15 W/mK.

Meter tails are in cavity until floor void so >>50mm. I need (want to) install a 100mA Time delay in meter box as this is TT. Safer to have some cut out I feel for long meter tails and that also should satisfy DNO and they have a short run to my RCD. 4DA1 is single core cable table so 2...

Hi, I've house remodelling underway and I'm looking at the electrics. The walls are planned to have 30mm thermaline basic (polystryene backed) plasterboard to improve the U value of the old walls and decrease the U of the new walls. I had thought that this would be method A, "enclosed in a...

That's presumably plasterboard with celotex or similar on the back. Boards with polystyrene on the back are half the price. Polystyrene is 0.040 W/mk where as celotex is 0.021 so you need ~20mm or polystyrene to match 10mm of celotex. Polystyrene isn't a vapour barrier I believe but if you...

Thanks. I'll have to try it.

I'm doing a bungalow to house conversion. Bungalow had E7 heating but there is now gas in the village so I'm going to put in gas CH with radiators. I need to decide how I plumb the downstairs rads. Do I carve out channels in the scree and then run pipes there? Or do I run 10mm pipes down the...

Do tell how :-).

You don't need to be connected to MET for an RCD to work. Or to put that another way, if the RCD works then there is another path. That path could be direct to earth and then to the power cable in the ground so not via MET. Otherwise RCD would not protect you mowing outside.

The CH will have a lot of plastic pipework so the bathroom radiator will be isolated by default. If it was all copper then it would already be connected to MET by boiler E connection so bonding under the bathroom floor wouldn't be needed or an issue. I see what you're saying re...

Hi, I've used Wickes ready mixed jointing compound in the past. I've found that very good and when it dries it seems water resistant so it doesn't soften and come off it you get it wet again (i.e. when painting or stripping). I've never used Gyproc easy-fill or Promix/Joint filler AFAIR. I...

That's my thought and assuming I put in the second connection in the floor void then if later someone says you can't have an external connection I would still have the one which could be inspected by cutting a hole in the floor under the bath. Although, strictly speaking the incoming pipe has...

But, getting back to point as we are drifting off topic, I reckon this: In order to be seen to comply with the regs I reckon that I should take a bond wire to the gas meter box so the bond can be seen and inspected. I think I'll also bond at what I think is the "correct" place, in the floor...

There are 2 assumptions that can be made. Body is insulated or body has good connection to earth. Worst case of those two is good connection to earth since if the body was insulated we could handle lives wires with no problem. So with that assumption, for safety, any other metalwork should be...

Playing devil's advocate, what about the case of a shower with the water running? There could be a continuous stream down to the drains underground and thus earth. Or for a bath you could touch earthy taps. Or holding a shower head with a metal outer that connects back to the water pipe. I...

By water potential I mean what voltage the water is at. Worst case is obviously wet person in shower/bath reaching for towel on towel rail. All metalwork wants to be visibly obviously isolated or at same potential as the water the body is standing in. I take your point about different earths...

I think the reasoning behind "consumer's side of an insulating section or insert" is that all gas pipes inside the house will be copper. This copper pipe comes through a wall and may get an earth from the wall itself, i.e. this could be below dpc so very damp, or the wall could have rising damp.

I agree. A case in point would be a shower cubical or a tap. These would be isolated or at water potential. I would tend to assume the worst, a cable fault under the floor which made the pipe live and hence radiator. Plastic pipe in the CH means the boiler bonding does not protect. If the...

I would imagine a meter box has a drain hole but that might be worse as with saturated ground that could introduce water. Supplementary bonding has to connect all exposed metalwork and the water pipes for it to be effective. Otherwise a fault raising the voltage on one item would raise it on...