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Can I fit downlighters with about 60mm of space above and VCL directly overhead?


Pete

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I have not decided whether to use downlighters or the narrow panel Led lights that some have used but my main concern is that I have my VCL directly above the lights. I know the led lights do not produce as much heat as the halogen ones used to but it still concerns what the heat long term will do to the VCL. I know I could put some form of barrier in place but has anybody had to deal with this situation? TIA

Distance from plasterboard to VCL is 120mm.

Edited by Pete
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I had a similar issue in my bathroom. Its a flat roof with Joists were 100mm deep with a additional piece on top to give it a slope for water drainage. After I had it insulated above you could clearly see the foil PIR through the gaps in the old roof boards. So i made some chipboard boxes and painted the corners with blowerproof and fitted a piece of EPDM as a makeshift cable grommet. Not only did it give me a bit of peace of mind that any heat wouldn't affect the foil, but it also allowed me to tape the VCL under the joists and into the boxes to maintain air tightness in the bathroom. 

 

IMG_20190318_211838.jpg.d32313d89b49a9d29f105c090d5370a2.jpg

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I originally had a lovely, airtight vcl between the ceiling pb and underside of 145mm joists. Multiple penetration now with said downlights, speakers etc. At each downlight I've carefully removed the pir in between the joists leaving the foil. You can just see the green vcl.

 

20180127_171954

 

The Thermahoods will  be stuck down to the pb with intumescent mastic then the whole thing foamed in. Flexible metal conduit will come out from the foam into proper conduit.

 

20180122_182057

 

20180122_182114

 

I'm aiming to this bond the Thermahood edge to the cut edge where the vcl is, to go some way to reinstating the vcl. The Thermahood will become part of the vcl in effect.

 

I can't do that with the body dryer so I'm going to line the vertical edges over the blue vcl with Asbestolux type fire proof panelling. All edges again will be intumescent sealed. This'll then be capped over with pink pb on an intumescent foam seal and a slab of pir over that. All screwed down for future access to the body dryer terminals. (Red Commando jobbie is a test plug from when I took it into work to try). This'll be wired again in galv conduit back to the board.

 

2018-03-03_07-53-00

 

Edited by Onoff
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I originally fitted downlighters with MR16 LEDs, then changed them for very low profile LED panel lights.  These barely get warm, and only project about 6mm behind a skimmed plasterboard ceiling (they project about 21mm up from the rear face of the front flange).  I'd say that there would be no need at all to protect a VCL some 50mm above these, given that they only every get around 10 to 20 °C above room temperature.

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Annoyingly because I can't find any low profile down lights that are fire rated. My electrician has demanded I put some kind of fire hood over them. We ended up going for intumescent blanket over the top of them. (fitted before the plasterboard goes up.) 

https://www.fireproofpaint.co.uk/shop/fire-barriers/fb70-fire-barrier-curtain/

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24 minutes ago, Construction Channel said:

Annoyingly because I can't find any low profile down lights that are fire rated. My electrician has demanded I put some kind of fire hood over them. We ended up going for intumescent blanket over the top of them. (fitted before the plasterboard goes up.) 

 

 

Look harder!

 

https://www.downlightsdirect.co.uk/shallow-downlights.html

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Bit late for that ? 

But in my defence I was looking for the bigger flatter ones like this

https://www.lampshoponline.com/15w-round-led-light-panel-200mm-26w-pl-replacement.html?gclid=Cj0KCQjw4qvlBRDiARIsAHme6ov66B6xY9cLEBSzhIxLOljk1eb9jepVIRY3KKp6MXR0HTEpmjPplUkaAjs5EALw_wcB

 

The blanket cost £100 to cover 27 lights so it's still its not that far out. Possibly even cheaper with the blanket. 

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