# Forum Home Renovation Lighting  LED Downlight plasterboard box

## bames

Hey all, 
I am soundproofing my ceiling with Rondo soundclips, furring channels and insulation. I am putting downlights in and now understand that putting in downlights will reduce the effectiveness of my soundproofing, so I decided to make a box out of 16mm fire stop plasterboard for each downlight sealed with acoustic sealant.  
The idea is that this would overcome the loss of soundproofing by achieving a sealed ceiling. 
I am now however concerned about the legalities of building such an enclosure, and any potential insurance issues I might have if something were to happen. I have seen multiple different clearance requirements for downlights, from 25mm to 200mm, and some that distinguish between incandescent/CFL/LED and halogen, and some that don't. Also checked with a few sparkies, and different sparkies give me different info. It's all very confusing and difficult to out what I can and can't do. 
I am using LED downlights with transformer that plug straight into a surface socket which has already been installed, so i really don't want to pay a sparkie to install as all they'd do is plug them into the power point and pull the little spring clips on the side back to hold it in place - not exactly difficult. 
So... can you legally enclose a downlight in a fire-rated plasterboard box? How big does the box need to be? Or is this not legal and I'd need to just buy sound/fire rated downlight covers? 
Thanks

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## Bros

If you have seen electricians there should be no doubt as there has been an amendment to the rules just to cover downlights.  
Now you say they are LED lights and there should be negligible heat generated so any box will do however if they are other heat generating lamp these conditions then are to be adhered to.

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## phild01

Just a consideration but some LED lamps run hotter than others.  They may have large heatsinks to aid heat dissipation otherwise their lifespan is reduced.  I suggest testing the lamp in a box of what you propose and check the temperature of the unit compared with it running in free air after a couple of hours.

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## Bros

Here you go this should shed some light on the subject.   http://updates.clipsal.com/clipsalon...s/W0001486.pdf

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## phild01

With my ceiling I wanted to do downlights but had to reject this for the same reason  as yours - sound proofing.  I am looking around at pendants instead.  Despite what you may hear, LED's are probably on par with CFL's for power usage and do heat up.

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## PhilT2

> Here you go this should shed some light on the subject.   http://updates.clipsal.com/clipsalon...s/W0001486.pdf

  Sect 6.2 of the clipsal brochure shows a distance of 50mm between light and transformer but appears to show the transformer sitting on the insulation. Am I reading that correctly? Seems to me that putting a transformer on top of insulation, especially loose fill type where it could sink into the insulation, would not be the best course of action. I realise the newer types of transformer don't generate the heat that older ones did but....

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## gpkennedy

We once did a fire rated, acoustic suspended ceiling. Bugger of a job. All droppers dampened, three layers of plaster. Over engineered quantity droppers, fire rated goop. Came back to job later and the sparkies had cut 6 holes through the lot for 3 tube fluro units. Bugger.

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## Pulse

Great idea, I've wanted to do this too. I would use heat shields which will legally allow you to reduce clearance <200mm, not that fire stop is flammable anyway... 
I think most heat shields have documentation with them, eg 25-50mm sides and 200 mm above.  
I would do a box as big as possible to allow heat dissapation, aim for 200x200x200 minimum. I don 't believe any law relates specifically to what you are suggesting though. Also use a luminaire with some ventilation around it. 
cheers pulse

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## Bros

> Sect 6.2 of the clipsal brochure shows a distance of 50mm between light and transformer but appears to show the transformer sitting on the insulation. Am I reading that correctly? Seems to me that putting a transformer on top of insulation, especially loose fill type where it could sink into the insulation, would not be the best course of action. I realise the newer types of transformer don't generate the heat that older ones did but....

  I do not know the drawing symbol used here but to make an educated guess it would be that this insulation was not the loose filled type. No problem a transformer on top of insulation provided it was solid and could easily take its weight.

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## FrodoOne

> Hey all, 
> I am soundproofing my ceiling with Rondo soundclips, furring channels and insulation. I am putting downlights in and now understand that putting in downlights will reduce the effectiveness of my soundproofing, so I decided to make a box out of 16mm fire stop plasterboard for each downlight sealed with acoustic sealant.  
> The idea is that this would overcome the loss of soundproofing by achieving a sealed ceiling. 
> I am now however concerned about the legalities of building such an enclosure, and any potential insurance issues I might have if something were to happen. I have seen multiple different clearance requirements for downlights, from 25mm to 200mm, and some that distinguish between incandescent/CFL/LED and halogen, and some that don't. Also checked with a few sparkies, and different sparkies give me different info. It's all very confusing and difficult to out what I can and can't do. 
> I am using LED downlights with transformer that plug straight into a surface socket which has already been installed, so i really don't want to pay a sparkie to install as all they'd do is plug them into the power point and pull the little spring clips on the side back to hold it in place - not exactly difficult. 
> So... can you legally enclose a downlight in a fire-rated plasterboard box? How big does the box need to be? Or is this not legal and I'd need to just buy sound/fire rated downlight covers? 
> Thanks

  Since you do not need to use a "tool" to remove and replace plug terminated devices in a pre-existing power outlet, I believe that you can manipulate the light fittings and any associated plug-terminated transformer as necessary. 
It appears to me that your idea is to build around each existing installation of down-light, (probably "electronic") "transformer" and socket a small box made of fire stop plasterboard.  Apart from the space required to be allowed between the LED down lights and any possibly flammable materials,  have you considered how you will access any fitting should it need replacement. 
In addition, please read Ban Incandescent Lamps?
While this site refers to the replacement of incandescent lights by CFLs, at about half way down the item"*CFLs in Existing Luminaires"* refers to the heat build up in enclosed "fittings" adversely affecting the electronic equipment associated with CFLs.  Much the same comments and heat build up problems apply to the electronic equipment associated with LEDs. (Have you noticed the relatively large heat-sinks built into many LED devices?) 
In the above article it is stated "Semiconductors (transistors or MOSFETs) will run fairly hot in most CFL circuits - in fact they are responsible for a fair proportion of the total losses within the system as a whole. These components must never be allowed to exceed a junction temperature of (usually) 150°C - and this means that the case temperature must be somewhat lower than the maximum permissible. The only way to get the maximum life from any CFL is to keep the electronics as cool as possible - preferably well under the manufacturers' recommendation of 50°C."   These comments also apply to electronic "transformers" and, in summer, roof spaces in Australia are often likely to exceed 50°C. 
I note that http://updates.clipsal.com/clipsalon...s/W0001486.pdf  referred to earlier includes the following -
Max. Ambient Temperature: 50ºC
Note: Do not cover downlight luminaries, as this product requires ventilation to maintain its performance characteristics. 
While your concern is with sound insulation, all down-lights pose a problem in the compromise of allowing any non-incandescent "lamp" to remain within its operating temperature range and the consideration of adequate effective thermal ceiling insulation.  Keeping the "transformer" outside the confines of any "box" would reduce the thermal "content" of the box, but this may be difficult, since the high current carrying leads between the "transformer" and the lamp are usually fairly short. 
However, after all these negative comments, a *possible* solution *may* be to make the top of the proposed box from heavy gauge uncovered aluminium and make it removable for future access. A* large* area *conductive* box cover _should_ be able to dissipate the heat build up from below and still provide sound insulation.

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## phild01

Again I have to say, the heat issue has stopped me thinking about LED downlights for my ceiling that needs to be sound resistant.  I have mucked around with LED lighting and destroyed quite a few.  I respect their need for cool running and why they have heatsinking.  It's for a reason.

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## justonething

I think you can have both, that is proper ventilation and adequate sound proofing, provide you have sufficient room in the ceiling to house a properly designed downlight box. To provide both sound proofing and ventilation, you will need to line your box internally with sound insulation material and also have a right angle bend so that as noise rises up, most of it get absorbed by the insulation lining and at the bend. You also need some form of mechanical ventilation with one of these 12V computer fan to expel the hot air into the ceiling space. All of that would require a bit of room, a bit of money and a bit of work. But it can be done.

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## GoLights

The Light box is a good idea, but it would also be a good idea to allow some ventilation. A few holes in the top perhaps? I understand this will compromise your sound proofing a tad, but its better to be safe than sorry.. 
Otherwise, use some track lighting. It's nice to look at, and still give you the downlight appearance, and can be cost effective. Food for thought.

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## phild01

The only way I can think of to ventilate the box would be to design a muffler that dampens sound but allows air to flow.  The Inventors program did show a ventilation system designed on this principle quite some time ago.

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