Is there really no right way to work with down lights and insulation?

[Boyyo]

Hi All,

I'm kind of hoping to get confidence in my decision to have spots fitted into the ceiling of our new extension, but keep coming across different advice...help would be welcome!

We're looking to fit 12 LED spots (Aurora Pro 6w) into a lean-to pitched roof, split into two circuits on dimmers. Room is 7.5m x 3.5m

There are Velux windows (3) and there will be 100mm Celotex between joists with 50mm underside of rafters, plaster board to be fitted as finished ceiling...roof is vented between tiles and Celotex.

So, I was going to have holes into the Celotex at 12 positions, the holes being double diameter of light fitting and with about 25mm gap between the rear of the light fitting and the face of the Celotex. There would be at least 25mm of Celotex left in bottom the pocket that is created which separates the LED from the vented roof.

I appreciate it will compromise the thermal integrity, but have seen arguments and statements from various LBC guys accepting that it's not the end of the world in terms of thermals, especially given the use of Velux...is this OK?

Does anyone have an input on the level of protection that's needed from a fire safety perspective, ie...the distance around the fitting?

Any input very welcome.

 

[Rpa07]

More and more manufacturers are taking the use of downlighting and insulation into account especially the integrated types that will be finned for heat dissipation hence cooling and also have a stand off cover for loose insulation like rock wool.
You do what you can to help some circulation and it sounds like you have.
The very worse case scenario is a failed light which will become apparent.

 

[telectrix]

have a look at JCC V50 fittings.only need 50mm above ceiling, and can be covered in insulation.

 

[Rpa07]

have a look at JCC V50 fittings.only need 50mm above ceiling, and can be covered in insulation.

Have you stepped away from the minisuns Tel or is that just for the lamps?
My go to for a 70mm hole is the V50 and have only had one driver go a day after fitting out of all that I’ve fitted.
It’s hard to try any others whilst the ones you fit don’t go wrong. I want to try FSR but have no reason to!

 

[suffolkspark]

Mirror the above, also the scolmore click inceptor micro which i think may need even less depth from memory

 

[Boyyo]

Thanks Gents,

If I understand all the info correctly, if I provide a reasonable distance around the fitting to ensure there's no insulation contacting the fitting, AND the fitting is 'fire rated', then the only thing I need to console myself to is that it's not making best use of the insulation..!?

That said the lights will be providing some localised heat of there own ;-)

I t would be the LBC that could pick me up on this I guess?

 

[Midwest]

I've done a few vaulted ceilings with down lights, and have had conflicting opinions from LBC.

Mostly, they weren't happy with cutting holes in the Celotex/Kingspan, reducing the u values etc. But as one of them said, the Velux windows don't help the u valves much either.

As regards the insulation covering down lights, most manufacturers I spoke to (which included JCC), stipulated only loose lay insulation can contact the luminaire, they require an air gap when covered with solid insulation, such as Celotex.

The last one I did, the client decided to under batten the joists, to allow a clear space for the down lights, void of any insulation.

That one I did, we used http://www.greenbrook.co.uk/eshop/f...-FR-Downlights-Technical-Product-sheet(2).pdf, which were 40mm height (I think), with 20mm air gap above.

PS with a vaulted ceiling, if thats what your doing, you really need the tilt down lights AND if you can afford them get the electric Integra Velux windows.

 

[buzzlightyear]

have a look at JCC V50 fittings.only need 50mm above ceiling, and can be covered in insulation.

https://scolmore.com/products/inceptor-picofg/try them .

 

[buzzlightyear]

have a look at JCC V50 fittings.only need 50mm above ceiling, and can be covered in insulation.

SCOLMORE GROUP | Manufacturer & distributor of electrical Wiring accessories & Lighting - https://scolmore.com/

 

[Midwest]

SCOLMORE GROUP | Manufacturer & distributor of electrical Wiring accessories & Lighting - https://scolmore.com/

SCOLMORE GROUP - OVIA LIGHTING | Inceptor Nano5, fire-rated, integrated LED downlight - https://scolmore.com/products/inceptor-nano5/
SCOLMORE GROUP - OVIA LIGHTING | Inceptor Pico FG, integrated LED downlight - https://scolmore.com/products/inceptor-picofg/
https://scolmore.com/_pdfs/inceptor_micro.pdf

 

[Octopus]

At the rate the green brigade are going downlights will be outlawed ...

 

[Midwest]

Shhhhhh, I got some of those Philips Hue lamps. Apart from being ridiculously expensive, they are...….quite good, if you like different lighting scenes, that is.

 

[Sparky Pat]

I have a similar situation at the moment. I like Midwest's idea of battening off, will put it to the client they were wary of cutting holes in the Kingspan and were going to use surface spots instead.

 

[GeorgeCooke]

Cant find a common agreement on insulation & down lights.... - https://www.diynot.com/diy/threads/cant-find-a-common-agreement-on-insulation-down-lights.512537/

 

[Octopus]

Cant find a common agreement on insulation & down lights.... - https://www.diynot.com/diy/threads/cant-find-a-common-agreement-on-insulation-down-lights.512537/

Not sure DIYnot is a serious forum - especially when it comes to sparking!

 

[Midwest]

Cant find a common agreement on insulation & down lights.... - https://www.diynot.com/diy/threads/cant-find-a-common-agreement-on-insulation-down-lights.512537/

I have to say, when I was learning in any profession, it always perceived to be impolite to ask the professional opinion of a particular person, only to ask another colleague almost immediately later.

Perhaps, tinernet is different?

 

[chris gray]

Celotex recalls five insulation product lines | Construction Enquirer - https://www.constructionenquirer.com/2017/09/14/celotex-recalls-five-insulation-product-lines/

 

[Boyyo]

I have to say, when I was learning in any profession, it always perceived to be impolite to ask the professional opinion of a particular person, only to ask another colleague almost immediately later.

Perhaps, tinernet is different?

Hello, I didn't mean to cause offence and was just looking for as much info as possible from a range of resources. You only need to see the differing opinions and advice you find from a single subject thread to realise the amount of contradictory advice on line...and i really like to soak up as much as possible. ;-)

T'internet makes it easy to do, but I understand it might look a bit rude, however, the info supplied is extremely valuable and I thank you for taking the time to provide it.