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loft insulation and Ceiling spot lights.

Discussion in 'General Chat' started by Saggy, Aug 23, 2007.

  1. Saggy

    Saggy Member

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    Hi all, with this cold wind I have noticed that the bedrooms feel a bit chilly. on going into the loft I found the electrician who fitted the pots to all the bedrooms has removed the insulation and not refitted in position. Is it ok to fit back over the lights or would that cause a fire risk? most of the lights are the mains version not the low voltage ones.

    Thanks

    Martin
  2. Paul_HDLover

    Paul_HDLover Member

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    Sure a sparky would answer this better, however I would be inclined not to insulate over electric components unless they are all securly cased.
  3. mad_matt

    mad_matt Member

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    I would not cover the pots with insulation, I think you will find you need to have at least 3 inches of clear space round the pots. Unless they have protective coverings and are fire rated.
  4. IronGiant

    IronGiant Moderator

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    Most mains lights get quite hot and you run the risk of them overheating/catching fire if you lay insulation behind them, I would get some professional advise unless one of the forum electricians comes forward.

    Dave
  5. RugbyAl

    RugbyAl Member

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    A sparky (who was fitting spotlights in my kitchen) told me he heard of someone who placed a terracotta plant pot (upside down) over each of is spotlights in his loft, and then insulated up to them. He said it worked fine. Most pots like that have a hole in the bottom to let the heat out.

    Would double check this though....
  6. loz

    loz Active Member

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    You could fit some of these
    http://www.tlc-direct.co.uk/Products/TLALC724.html

  7. Saggy

    Saggy Member

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    thanks all, those loft caps look like what i need but going to need 20 of them . The terracota pots sound interesting.

    regards

    Martin
  8. Uridium

    Uridium Active Member

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    I thought loft insulation fibre was fire retardent nowadays?
  9. mjn

    mjn Active Member

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    I just used small "pots" and had no problems so far.
  10. Pat_C

    Pat_C Member

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    So did I, and I'm pretty sure that it has to be. But the light units could still overheat and catch fire if covered.

    I have gaps in my loft insulation around the downlights in the ceiling.
  11. loz

    loz Active Member

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    I think I know what you mean.
    I have 12 downlighters in the kitchen and breakfast room (that has loft space above)
    I have 10 in 2 bathrooms, and 5 on the landing
    and am just about to put 12 in 2 bedrooms.

    so, 39 x £7.50 + VAT = £349 :eek:
  12. Jenn

    Jenn Member

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    We've used terracotta pots above the bathroom, got some that were quite big with a hole at the bottom and put the insulation back around and it's been fine for about a year now.

    But I'd check with a professional before just in case.
  13. johntheexpat

    johntheexpat Active Member

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    How do the terracotta pots sit with the building regulation that says you need a vapour seal between the loft and living space, (as posted by loz) if the pots have a hole in them?

    The low voltage lights also get warm, 'cos 50W is 50W no matter what the voltage.

    The only positive solution I have to offer, is LED spots as sold by Lidl in France, hopefully to be sold in the UK soon. I did a somewhat unscientific review of them in the Global Warming forum, they are not bad, not great, but the mains voltage (E27) version has a power output of 0.9W and only ever gets warm to the touch. Better LEDs are just around the corner apparently, which should negate the need for much of this heat protection.
  14. IronGiant

    IronGiant Moderator

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    I have 4 spotlights, so I think I may well get some for mine :)

    Dave
  15. loz

    loz Active Member

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    I was going to say exactly the same.

    If the concern is about insulation, using something with a big hole in it isn't the answer :lesson:

    If anything it is going to have a chimney effect, and cause even more draft, as the hot air from the light rises through the hole and pulls the air in from the room below
  16. Jenn

    Jenn Member

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    Big hole.. We're talking a hole about half an inch in diameter so it's not quite the same as 2x3m worth of ceiling with no insulation above whatsoever.
    Also the air from the room below isn't supposed to go up into the loft: the spotlights are fitted in holes the right size. If you look at a normal light fitting, the hole for the cables coming down from above the ceiling is quite big (maybe 1" diameter?) and would cause more air to go up than spotlights.

    As for building regulations to be honest I don't know but as said above the amount of air coming from the room below should be minimal and I would guess not enough to cause any condesation in a loft that's ventilated as it should.
    Before we got the boiler changed there was a water tank in the loft which although was covered, was by no mean sealed and would have been more of a concern regarding condensation.

    I certainly don't say that the pots is THE solution; it's just the one we used for 3 spotlights and as I said before it's best to talk to a specialist.
  17. John

    John Moderator

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    OT , but
    50W GU10's ? :eek:
    May I suggest you swap them out , if/when required , with 35W ones for an instant 30% saving in you leccy , and where you can, fit dimmers for further savings . 37 GU10's , who needs central heating :smashin:
  18. Mr Incredible

    Mr Incredible Well-Known Member

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  19. dunks517

    dunks517 Member

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    I was advised to put lengths of drainpipe over the lights, they are around 15 cm in length and have a nick in the bottom for the cable.
  20. loz

    loz Active Member

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    But you haven't counted the other rooms. That was just the ones with loof space above :) There's another 26 GU10s (just counting quickly in my head). Plus other forms of lighting of course in other rooms. The kitchen and breakfast room besides the 12 downlighters has another 12 LED lights and some cold cathode tubes for effect. And I could probably find 50+ halogen capsules if I started counting :eek:

    Actually, every room does have dimmers. And it isn't like we leave the lights on in every room, every night...
    I also have them on separate circuits in some rooms. So the 2 bedrooms for example I am just doing have 4 on one, and 2 on the other (just over the bed).
    I even have some LED GU10's and R50s now :smashin: (but they are not dimmable :thumbsdow)

    (my wife is into mood lighting, and likes every room to have an option from a single candlelight to the blackpool illuminations)
  21. Sonic67

    Sonic67 Active Member

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    From what I can remember from the regs laying cabke on top of thermal insulation reduces the cable insulations effectiveness by 25%, laying under the insulation reduces the effectiveness of the cables insulation by 50%.
  22. IanWilky

    IanWilky Member

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    There is always confusion over this matter. Building regs, as found in Loz's earlier post state that insulation should be laid with no breaks or gaps.

    There is nothing in the electrical regs about laying insulation over light fittings, nothing is ever stated in black and white like this within BS7671. What they do say however, is that electrical equipment and fittings should be fitted to the manufacturers instructions, which should state which BS the fitting complies to. In short, with these kind of fittings the instructions will state in some form or other minimum distances between the fitting and surrounding materials, if you don't follow these instructions, you are in non-compliance with the electrical regs by default.

    The only way to comply with both Building Regulations Document L (for loft insulation) and BS7671 (the IEE regs) is to use a device to hold insulation away from the fitting, creating the required airspace and which is in itself heat resistant. This makes terracotta pots perfectly acceptible to the electrical regs.

    You now need to consider the other building regulations;

    Part B - Fire Safety; this is basically the ability of the fitting to retain the fire rating (in hours) of the ceiling which you have punctured. This is applicable when the ceiling stops fire from spreading from one dwelling to another (i.e. in top floor apartments or flats with a shared communal loft. It is not usually required from room to room in a single dwelling unless the property was specifically constructed with this in mind e.g. disabled or special needs flats / bungalows.

    Part E - Acoustics; as fire above, however for the ability to prevent the spread of noise.

    Vapour sealing - how much vapour are we really talking in the real world? the only vapour in any quantities to cause problems comes from the bathroom. Spotlights in these areas should be sealed to IP65 anyway. Is your loft hatch vapour sealed? Use silicone or mastic to stick the terracotta pots down.

    Remember that as building regs change and develop, you don't have to rectify everything in your house. You only need to comply for new works repairs or additions. A 1960's semi for example would not comply with half of the current building regs, but you are not required to rebuild it before you sell it, unless you have made modifications that do not comply with the regs in place at the time of modification.

    Remember that GU10 lamps emit their heat forwards (into the room) which helps. Low Voltage MR16 on the other hand usually emit heat backwards into the fitting. Also think about your transformers if you have low voltage fittings. These should be positioned above insulation and as far away from the fitting as the leads allow.

    Possible solutions:

    For older houses - terracotta pots (make sure the size is half decent, i'd go for 2 -3 " all around the fitting)

    For new houses - Loft Caps / intumescent 'witches hats' / sealed fittings which are Part B, C and E compliant. These fittings are becoming much cheaper and more available, they are fire, acoustic, and vapour rated. Interestingly, they have ventilation holes in the rear.

    As Mr Incredible has suggested, the new energy efficient fittings be it CFL or LED are very effective and cool running, however as the fittings have the ability to be retrofitted with 'hot' lamps, it is still the installer's responsibility to provide the same protection as described above.

    As Johntheexpat said, 50W is still 50W no matter the voltage, low voltage downlighters actually tend to run hotter than mains.

    Sonic67; covering cables with thermal insulation reduces the cable insulation's effectiveness at dissipating heat, thereby increasing the temperature of the copper conductor which in turn increases its resistance (and therefore generates more heat still)

    This is not against electrical regs, however you have to apply a correction factor to cables run through thermal insulation to lower the current carrying capacity at which the cable can be used safely used.


    I use plant pots in the loft (my house was built in 1972), and nothing in the ground floor ceilings (vacuumed free of debris, no thermal insulation).

    Hope this over long post doesn't cause more confusion than it solves!
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  23. loz

    loz Active Member

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    Thanks Ian for a very informative post.
    I was going to ask some of those questions myself. Particularly about fire regs and whether I needed to worry about that in my detached house.

    Of course compliance is one thing, but even if it doesn't effect me, I wonder if I should still fit fireproof downlighter fittings anyway, given the price of them is reasonable from the likes of screwfix and TLC.

    What I wasn't sure about is do the fireproof downlighter fittings allow you to run the loft insulation right over them, or do they still need room for ventilation? (so are no benefit from that perspective and I still need to put pots over them)

    Another basic question (sorry to take it slightly OT). Am I allowed under the new regs to fit a set of downlighters myself? They would be wired into the existing circuit that supplier the usual ceiling rose. So no new spurs as such. I understood that is OK.

    What about if I add 2 sets of downlighters in the same room on different circuits as I originally planned, and replace the existing single switch with a double? (which effectively means new wiring I suppose) Can I do that?
  24. IanWilky

    IanWilky Member

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    Hi Loz,

    I understand your feelings about the fire proof downlighters - if you feel more secure fitting them then this is worth doing. Should the worst happen and you have a fire in one area, if they buy you that extra bit of time to get you and your family out then they can only be a good thing. I would have gone down this route myself but i wanted the square type made by Aurora, and unfortunately these aren't available fire rated.

    I have just dug a set of instructions out from the Click range and they say "This fitting requires a distance of 50mm of free air around the sides and a distance of 20mm of free air above it" so you will still need something to keep the insulation from resting on it. If you have a few in a line, maybe this could be achieved by fixing two wooden battens across your joists 50mm from each side of your fittings? this way the insulation will lay across these with at least 50mm space all around if you use 50 x 50 battens.

    As for what you are allowed to do yourself under Part P:

    Remember that the IEE regs and Part P are completely different entities. If you do any work yourself, if it is done properly it will comply with BS7671. Part P of the building regs however (in a nutshell) does not allow any alterations or additions to fixed wiring without the proper certification by a 'competent person'.

    Basically, if you change a downlighter, as long as you do not alter the fixed wiring i.e. the twin and earth, this will only constitute a fitting change which you are allowed.

    If you want to add lighting points / circuits / switching arrangements etc then this work will need to be certificated to comply with Part P. Your official options here are:

    1. Get a Part P approved electrician to do the lot and leave you with a certificate.
    2. Do the work yourself and get the work tested and inspected by a Part P approved electrician
    3. Do the work yourself and have it inspected by your local building control (this will need to be done twice - once at first fix, then at 2nd / final fix).

    Your unofficial option (which i am not suggesting you do) is to do the work yourself and say nothing. After all, who is going to come and check? This is the problem with Part P - it has become expensive and complicated to the consumer.

    Part P is a bit of a shambles. It was a good idea in that the aim was to get rid of cowboys in the way that Corgi helped the gas fitters, however its execution has left many problems. It is now possible for any Joe from a semi-electrical / diy background to pay his 700 quid, do the minimum to pass the course and be regarded by the public as a safer choice than a genuine electrician who up until now could issue a certificate in his own name.

    I have been in the electrical contracting trade for 13 years within an NIC EIC and Part P approved company and studying for 10 of those to reach my present position. Unfortunately, I am regarded as no longer safe to do any electrical work independantly, but kitchen fitter Joe is.

    Anyway, rant over, hope this helps :)
    • Thanks Thanks x 1
  25. loz

    loz Active Member

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    I think the key problem is genuine lack of public awareness of these regulations. If I didn't frequent forums like this, I am sure I would go on fitting new light fittings and switches in my home as I have done for decades...

    I guess there is something in the instructions that come with the new light fitting. But who ever reads those... :rolleyes:

    As far as who is going to check, is it likely that surveyors, especially with these new house pack thingies, would ask to see any certificates if they thought there was new electrical circuits? Are they likely to look closely anything that isn't an obvious bogged job with wires hanging out. Or isn't that in their remit?
  26. Jenn

    Jenn Member

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    As I understand it you're allowed to to change the light fitting as long as your not adding to the circuit (swap and existing light for a new different one). Same with switches, extractor fans etc.

    I wouldn't modify the circuit myself anyhow, it's beyond my abilities.
  27. PrettyGreen

    PrettyGreen Guest

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    I had the insulation in my extension redone last year when I had 12 240v downlighters installed. It was replaced with Kingspan insulation, which is about 4 inches thick and had holes cut in it to the diameter of the light fittings, no bigger, and Building Control had no problems with it.
  28. BandWidthJunkie

    BandWidthJunkie Member

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    I just in the process of doing up a new home I have brought and was thinking of downlights in all the rooms.

    I thought I would have: -
    9 in living room
    4 in dining room
    9 in kitchen
    1 in utility room
    1 in downstairs WC
    3 in hallway
    2 on landing
    4 in bedroom 1
    4 in bedroom 2
    4 in bedroom 3
    2 in bedroom 4
    4 in en-suite
    3 in bathroom

    a total of 50 for the whole house and I thought I was having a lot :eek:

    All I need to do now is find an electrician that wants to do the work :D
  29. IanWilky

    IanWilky Member

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    Exactly

    And if i didn't frequent forums like this i would have ended up with the Bose all-in-one i originally came on for an opinion for :D


    This could be likely, we have yet to see what these house pack thingies require, but i suspect it will be a current periodic inspection or electrical installation certificate.
  30. peter291

    peter291 Member

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    I know this was discussed many years ago, but this discussion helped me with valuable information recently so thought I would post a response.

    Last week our loft was fully insulated with 250mm thick material and we have a lovely warm house for once. Previously there wasn’t any insulation what so ever and with a young family something had to be done. Upon checking the work, I noticed that the contractor had simply cut around all the 15 down lighters we have in the loft area leaving a small tunnel effect of about 100mm dia through the insulation. I had a feeling this wasn’t right and was concerned as to the fire hazard.

    I checked the net (found this site) and realised that protection was required.

    As there were 15 down lighters (hall landing and bathroom) I did not want to use flowerpots due to the combined weight on the plasterboard ceiling. I also discovered that the professional system of covers would cost me in region of £180, which with a young family I could not afford.

    So my partner and I had a thought and came up with a low cost idea. We went to the Range store and purchased 15 plastic 25cm dia microwavable heat resistant mixing bowls. These cost just 79p each.

    After spending a few hours cutting out the bottom and a split down the side to get under the wiring, these bowls now sit over all our down lighters, the insulation can go up to the bowl as they are sufficient dia to protect the lights and any heat production funnels out of the top.

    Yes it now looks like the invasion of the Dalek’s in our loft as all you see is domes through the insulation, but its safe and works a treat.​

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