I take it that you also realise that all that is 'mandatory' (per the Building Regs) is ....
... and that is sufficiently vague (particularly as regards the meaning of "adequate") as to result in a pretty wide spectrum of interpretations!
extractor fan isolator switch
- Thread starter akist
- Start date
... and that is sufficiently vague (particularly as regards the meaning of "adequate") as to result in a pretty wide spectrum of interpretations!
No John, it could be a benefit to leave the light on to see what you doing whilst attempting to service , clean or change an extractor fan so with a 3 pole “isolator” you could decide which option best suits at any given time.
1/ all operational at the same time.
2/ extractor fan isolated - safe to clean, exchange, remove but light still functional
Without a timed overrun and permanent L both switch on and off simultaneously so no isolator required but you might add one if you want to service the fan whilst still using the light
Unless I misunderstand your comment?
Yes I am aware it is somewhat vague but I thought there is something more than that for locations of high humidity.
However BCO has the requirement to ensure the property is habitable which includes ensuring the mushrooms don't grow. (we open the window when bathing to prevent mould) We see so many properties in news reports with thick black mould and who does everyone blame? Usually the council. They insist on fans to control the ventilation/mould and others insit they are not required. It's a no win situation for them.
One of our rental properties had several tenants with no issues with mould and suddenly we got a letter from EHO, the bedroom in particular was horrible and very surprisingly a couple of ocassional tables in the lounge.
The tenant had blocked the trickle vents on each UPVC window and the bathroom extractor fan and of course denied it. But the bigger problem to work out was the tables, they had stickers from a second hand shop and taking the photos to them they were able to identify the source and still had some more from there in stock, a nice looking chest of drawers but pull a drawer out and turned it over to find the same green mould. Further to that, during a spot visit we found 5 people sleeping in the steamed up bedroom during the day.
To satisfy EHO we had to get several 'experts' in to survey and report and every one of them mentioned ventilation.
It took several repeated cleans and decoration to kill the spores and restore it. I hate to think what the cost was, not just for us but also the freeholder whos costs were dispersed to the others in the building... And all due to an IQzero.
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I wasn't denying that (although not having an isolator would be a pretty trivial,and rare, 'inconvenience') but, as I said, a similar argument could be applied to most 'hard-wired' things.
For example, if there were more than one light fittings in a room (maybe 'countless' ones, in the case of the dreaded downlights!), you presumably could argue that each should have an 'isolator', so that "attempting to service , clean or change" any one of them could be done with some/most of the lights 'functional'!
I don't really get that, since ....
I thought that was the primary argument for having an isolator?
I think "somewhat" is probably a bit of an understatement, but that sentence is the only relevant part of Part F of the building Regs (the only other sentence relating to a requirement to install and 'test' any mechanical ventilation such as it achieves what is required by the first sentence).
I think that all is required (or, I would imagine, actually 'allowed') of a BCO is that they ensure compliance with the (very vague) requirements of the Building Regs (as above). In this case, the consideration you mention is presumably covered by the BCO's (personal) view/opinion as to what constitutes "adequate" ventilation.
It seems that it i commonly the case that BCOs will not request/demand an extractor fan if there is an 'openable window' - even though they must (ought to!) realise that the window may well never be opened - but they nevertheless regard that as "adequate"
We have seen a number of post on here where BCO have insisted on a fan despite there being an opening window, I think even one of our own members had that.It seems that it i commonly the case that BCOs will not request/demand an extractor fan if there is an 'openable window' - even though they must (ought to!) realise that the window may well never be opened - but they nevertheless regard that as "adequate"
We have - but my personal experience is that a substantial proportion of them do not insist on extractors when there is a potentially openable window.
As I've said, the regs/'law' are so incredibly vague that there is bound to be a lot of variation in what individuals (including individual BCOs) regard as "adequate".
This has to be a regional thing, My experience feels like majority insist on fan.
Even going back to 70's when I did a load of casual work for a builder the inspector would ensure that every space using hot water had a working fan whether it appeared on the planning approval or not, some of his houses were very big and all had at least a basin in every bedroom. I think we got to about 18 fans in one property and every space had an opening window.
More recently I see the councils red additions on approved plans. A neighbour added 2 big bedrooms on top of a 2 bed bungalow, both with ensuite and the new master bedroom has and a dressing room and wardrobe but no doors, just 4ft wide gaps in the walls, however there 5 basins in five of the six spaces and each was amended by BCO as requiring a fan along with the 4 in the altered spaces downstairs, yes they were put in despite the (I think) 9 or 10 windows upstairs, the inspector was adament they were required and wouldn't sign off without them. There was talk of fitting a ventilation system but the complication of incorporating the downstairs rooms the cost was prohibitive and The last I knew they were all switched off.
I must add a comment to this and say the planning process was long and tortuous and went through 3 appeals processes as it is not in keeping with much of the surounding and the disputed need for an 8m square garage with office above (didn't happen), then a number of things were not as the plans, one being the height which is maybe a couple of feet higher due to the minimum angle of the tiles used etc. So I do wonder if there was an element of sour grapes involved.
I know that architects tend to automatically show fans now to avoid them having to be negotiated.
That's possible.
I suppose I'm not all that surprised, but would hope we can agree that such is just plain silly (and illustrates the problem resulting from individual BCOs being able to apply their own opinions about "adequate")?
Apart from anything else, when hot water is "used" in any room other than a bathroom, it is usually for very short and very infrequent, periods of time .... and I wonder how the BCOs feel about the "energy (in)efficiency" of having umpteen fans pumping expensively-heated air out of the building?
Oh I very much agree.That's possible.
I suppose I'm not all that surprised, but would hope we can agree that such is just plain silly (and illustrates the problem resulting from individual BCOs being able to apply their own opinions about "adequate")?
Apart from anything else, when hot water is "used" in any room other than a bathroom, it is usually for very short and very infrequent, periods of time .... and I wonder how the BCOs feel about the "energy (in)efficiency" of having umpteen fans pumping expensively-heated air out of the building?
However it's not only regional, it happens within departments too and sometimes by the same person over a short period of time, some years ago a very good friend on mine wanted to extend his grade 2 listed cottage and add a large garage, various designs drawn up, eventually the official (title something like listings officer??) passed an opinion on something which would be acceptable to him and aided the extension through planning permision, between him and BCO they allowed what I'd call a pile of tish, looked nothing like the original half dozen different alterations dating back over 300 years, is was cold and therefore damp. Only 5 years later he and his wife had passed away and their daughter moved in, wanting to get what was supposed to have been a bedroom suitable for use called in the same listing officer who attended site with the same BCO from before and both were appalled at the extension, the idea of demolishing it and starting again was very quickly accepted by both, not only that some of the original ideas were found to be acceptable.
The garage was also questioned, the origional idea was a loft within a peg tile sloping roof but he was only permitted to do a flat roof which looked so out of place amongst all the other outbuildings and he constantly had leak problems with, the officials criticised the shapethen suggested a sloping roof and again original plans were resurrected. I was hoping to show streetview images but being way down a country lane there is only one date listed.
Poor ol' Ted must be spinning in his grave.
I've even known a pair of semidetached housed altered at the same time but indivudual PP applied for being treated differently and then the inspectors suggesting the alterations being made to match each other rather than the BCOs amendments.
That's the problem with regs so vague that they leave so much to the opinions of individual BCOs (or whoever) - which, as you say, not only can vary considerably from individual to individual but even in the same individual at different points in time.
This makes life very (I would say 'unreasonably') difficult for those of us who have to 'satisfy' such individuals. This problemis likley to arise any time a BCO (or whatever 'official') is left to make their own decision about whether or not something is "adequate".
However, as I've recently written, problems may well arise if regulations are too detailed and 'prescriptive' - but I feel sure that there must be a reasonable and sensible 'compromise' which could be found!
Yes I think there is a benefit ,potentially, for most hard wired things to have an isolator .
Many light fittings in a room - yes agreed, one such installation for a pal of mine involved the use of a plethora of the click type etc plug and socket thingys , the idea being that one line could be isolated or the required number of fittings and still leave many of the remaining lights whilst working/testing the ones taken out of service, quite a lot of connectors but the “relative simplicity” for such changes or fault finding might be a worthwhile endeavour, although I do realise that many might think it a waste of time and effort.
In fact I did explain it to a builder pal and he attempted it but I had to end up making a couple of site visits to explain that he needed more connectors and to show him how they should be wired , in the end it did have the benefit that he could add additional light easily later on , so he eventually did understand the concept.
Plus , the first example I mentioned had some SELV units too so two different makes gave us the advantage of using blue connectors for mains operated an green connectors for SELV connectors and the advantage that once wired they were not accidentally interchangeable either.
As said future additions and alterations made easier but I’m sure that some of you will think that I am stark raving mad (even some that might not have actually thought so until now
).Anyway, back to the plot, yes some kind of isolator on things can be an advantage.
No-one can deny the literal truth of those statements.
However, as always one really has to consider the magnitude of the 'advantage' and, more to the point, the cost/risk-benefit situation . For example ....
Fair enough but, as above, if, for example one were talking about, say, a dozen downlights, the brief and once-in-a-blue-moon 'inconvenience' would have to be balanced against 48 (24 L/N terminals and 24 plug/socket contacts) 'additional potential points of failure' (theoretically 'fire risks'.
I conceded that there may be other reasons for using such plug/socket things, but suspect that you might agree that to have 12 DP switches would be a bit silly? ....
See above
My BCO has demanded a fan if the bathroom is new, regardless of a window, and said a fan is not needed if the bathroom has a window and it is old (for example refurbished as part of more general work). To me, it sounds like a very grey and discretionary area. Especially paragraph 3.31
3.31 If there is no ventilation system in the original room, it is not necessary to provide one in the
refurbished room. However, additional ventilation may be necessary if refurbishment work is likely
to make the building less compliant with the ventilation requirements of the Building Regulations
than it was before the work was carried out. The guidance in paragraphs 3.6 to 3.13 should be
followed for refurbishment that includes energy efficiency measures and paragraphs 3.14 to 3.16
should be followed for window replacements.
3.31 If there is no ventilation system in the original room, it is not necessary to provide one in the
refurbished room. However, additional ventilation may be necessary if refurbishment work is likely
to make the building less compliant with the ventilation requirements of the Building Regulations
than it was before the work was carried out. The guidance in paragraphs 3.6 to 3.13 should be
followed for refurbishment that includes energy efficiency measures and paragraphs 3.14 to 3.16
should be followed for window replacements.
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