REPLACING PENDANT LIGHT IN BATHROOM WITH LV DOWNLIGHTS

[Tidjypudds]

Hi, can anyone tell me how to do this please?
Does each downlight need its own transformer?

 

[ElectricDunc]

Depends how you decide to do it. You could run them all of one transformer if you wanted but that's not really common practice these days. A transformer on each light is the method i use as in the event of a transformer failure only one light will go out. You do realise that this work comes under Part P and is notifiable to your LABC.

 

[Steve]

aye, LABC wont be open today either . . .

 

[ban-all-sheds]

REPLACING PENDANT LIGHT IN BATHROOM WITH LV DOWNLIGHTS

http://www.diynot.com/wiki/electrics:voltage-bands


As ElectricDunc said, this is notifiable work, and since it's notifiable there's no way you're going to be able to get Building Regulations contraventions past the BCO. It isn't just Part P that you have to comply with, it's all of the relevant regulations, and Parts C & L are immediately obvious hurdles.

If you've got a roof space over the bathroom then you will have to completely seal around the lights as you must prevent warm moist air from entering the unconditioned space because if you don't you'll get condensation up there - a contravention of Part C.

Part L problems are twofold - if there's insulation in the loft then you cannot remove it, because if you do that will make the degree of insulation worse than it was before, i.e. your degree of compliance with Part L will be less satisfactory than it was before. But you can't leave the insulation in place because the lights will require a clearance all around them to avoid overheating, so you'll need to install some kind of structure around the lights to provide clearance and to allow the insulation to be maintained.

See these for details of keeping insulation, providing space around the lights and sealing against moisture:

http://www.nhbc.co.uk/NHBCPublicati...ical/StandardsExtra/filedownload,16553,en.pdf

Pre-formed cap to seal downlights: http://www.aico.co.uk/firecap_loftcap.htm (It's NOT a firehood....)

The second Part L issue will be the efficiency of the lights. Since you mention transformers I'm assuming the lights you plan to install use 12V halogen lamps. These will not be efficient enough - even though the Building Regulations don't actually mandate luminaires which cannot take incandescent lamps that is what Approved Document L says you have to use for a certain percentage of your lights, and rightly or wrongly many councils regard that as mandatory, so you could have a real struggle to get ELV halogens passed.


Also the whole thing is crazy anyway. What is the wattage of the light you're removing?

How much greater is the combined wattage of the ones you plan to replace it with?

How sensible is it to deliberately make your lighting significantly less effective than it was before thus requiring a large increase in the amount you have to have in order to light the room as effectively as it was before?

(Hint - it isn't sensible at all).

Don't do it.

 

[JonoPashley]

Honestly i dont like DLs if they can be avoided. You can get some very nice fittings that you can just exchange with the pendant fitting.

http://www.thelightingsuperstore.co.uk/product.asp?productid=41849

Will provide high light levels, its a energy saving lamp. Removes the issues with part L. However im unsure weather this would be classed as a straight swap and thus exempt from notification, BAS will probably know.

 

[ban-all-sheds]

It's a replacement, so not notifiable.

Downlights aren't just replacements (well, the first one is, but 1 single downlight isn't going to work very well), you're adding lights, so it's notifiable.