by ericmark »
Thu May 19, 2022 10:25 am
I seem to remember one of the parts of the building regulations at one time said the fan in a bathroom with a window which does not open must be able to run without turning on the light. This has now been removed, but it resulted in the use at one time of double pole light switches for the bathroom so a second supply could activate the fan without turning on the light.
Typical was a push button timer as well. But at the time I was not working on domestic, got a feeling is was some thing to do with Part L of the building regulations, which also caused problems with bulb holders which could not take tungsten bulbs, with three instead of two holding pins on the BA22d bulbs, and a dimple on the GU10 L2 bulbs.
Regulations state:- "514.11.1 A notice of durable material in accordance with Regulation 537.2.1.3, shall be fixed in each position where there are live parts which are not capable of being isolated by a single device. The location of each disconnector (isolator) shall be indicated unless there is no possibility of confusion." That is from BS 7671:2008 with BS 7671:2001 it also states:- "514-11-01 A notice of durable material in accordance with Regulation 461-01-05, shall be fixed in each position where there are live parts which are not capable of being isolated by a single device. The location of each isolator (disconnector) shall be indicated unless there is no possibility of confusion. " sorry not got any older copies, but I would not expect there was not a requirement in BS 7671:1992 saying the same, so the builder (Persimmon) is seems were not following regulations, which since my daughter has a Persimmon home of around that era does not surprise me, there were a lot of poor practices at the time, with no neutrals to the wall thermostat which resulted in a high hysteresis, and earth wire missing from the hot water tank thermostats where the green/yellow wire was used for a live rather than use 4 core cable.
Around 2004 the Part P regulations came in, and the use of semi-skilled labour to install electrics came to an end in the main, and kitchens for example were wired by electricians not kitchen fitters, and the same with central heating electrics, also the installation certificate was actually completed, there was a change around 1992 when the regulations became a British standard, but it was not until the installation certificate was in theory required to get a completion or compliance certificate that homes were actually inspected and tested on completion.
Since every 10 years one is suppose to get an EICR or PIR as it was called, then after 20 years it would be hard to show a builder was at fault without also showing you as home owner also at fault, in the main the move to fit RCD protection has highlighted many of the faults, I know with my own house, the wrong neutral was selected for some lights likely on original wiring, but only found when RCD protection was added.
In 2008 the earthing requirements were relaxed in bathrooms if RCD protection was present, it was becoming a problem due to the amount of plastic pipes being used. In 2021 in England a new law came out for landlords forcing them to have an EICR done, this resulted in many failures due to no RCD where bathrooms had been refurbished and earths not connected.
So in real terms one should be thinking about RCD protection, yes there is a down side where one can trip causing freezers to defrost, but use of the RCBO (RCD and MCB combined) in the main removes the problem.
There has also been a move to using electronic equipment where the electronics are before any step down transformer, LED lights for example, so today we fit a surge protection device (SPD) in the consumer unit (fuse box) this is not for safety, but to stop items like TV's and other items with switch mode power supplies from being damaged, the problem is when they are damaged no one can point the finger and say a SPD would have stopped it, so take up is slow.
However you need to consider a consumer unit (CU) change, to include RCD and SPD protection, which would include a basic EICR which they need to do to find lurking problems like borrowed neutrals.
I fitted two RCD's in my own house in around 1992 when my 14 year old son got an amateur radio licence and I wanted to protect him, and it has cost me in that time around 3 freezers full of food, but also ensured he was not injured when he played, back then could not get the modern type of CU with all RCBO's so no option but just have two RCD's but this house is all RCBO, the extra £200 is nothing if it saves just one freezer full of food.
