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Posted By Topic: Downlights with loose fill insulation

Bilby42
Dec 12 2018 22:10

This question was discussed several years ago, but technology has moved on since.

Have an installation with loose fill insulation and existing open can downlights. I can replace existing downlights with IC-F fittings, but even these require the loose fill insulation to have a 90degC rating.

As its almost impossible now to determine what the original loose fill insulation's temp rating was and its difficult to access the ceiling space from above to fit a high temperature insulation plug around the existing lights, I'm at a loss to decide the course of action.

I'm considering leaving the existing open downlight fittings and using a Potter downlight cover (which can be installed from below), although it appears these are actually designed to prevent a room fire entering the ceiling space.

Alternatively I could "assume" the existing insulation can handle 90degC and use IC-F fittings, although "assuming" doesn't feel right.

How is everyone else handling unspecified loose fill insulation with downlights in 2018?

   

Bilby42
Dec 12 2018 22:14

Slight correction: Previous post should have said "its difficult to access the ceiling space from above to fit a high temperature insulation plug around replacement IC downlights"
   

daniel2
Dec 12 2018 22:55

From experience (an error on my part) after installing replacement LED downlights for the old Superlux SD100 downlights I discovered 'popping' sound. Some manufactures state not to install their fittings in loose fill insulation ie 'Insulfluff'. I think the fibres work their way onto the hot electronics and burst making a popping sound.
   

Satobsat
Dec 12 2018 23:36

There are companies that will remove loose fill insulation with specially equipped vacuum cleaners. Maybe try that in the area where the lights are? They should also be able to help with replacement insulation material for inaccessible roof spaces. The existing loose fill will most likely have lost all it's loft and most of it's effectiveness anyway.

   

Satobsat
Dec 12 2018 23:38

Here is a modern loose fill insulation product.

http://insultech.co.nz/roof-insulation-products/
   

rarrar
Dec 13 2018 03:45

what size is the hole? if it's large enough reach in the sqaure it's installed in and remove the insulation, then get a square of modern insulation and install that will match the downlights rating this prevents the insulation coming back in this square....
   

AlecK
Dec 13 2018 08:27

Very few forms of BTI have a 90 degC heat rating, as far as I have been able to find out.
Some don't specify it in the form indicated by the downlight Standard; but have a "maximum service temp" which seems near enough the same thing. Most types of batts etc use binders that are only rated for 80 degC; above that they break down over time and the "batt" turns into loose fibres. Certainly wouldn't assume old insulfluff is OK; it's basically munched-up newspaper with a fire retardant added.
   

Bilby42
Dec 13 2018 08:28

Appreciate answers guys. I've just discovered a better range of products from Firepro. Their FF109 looks like it will do the job, and I can fit it from below the ceiling. I have a suspicion that most installers use IC-F fittings thinking this solves the insulation ignition issues. Certainly what all the lighting suppliers imply.

Disclaimer: I'm not associated with Firepro in any way!
https://firepro.co.nz/section2
   

AlecK
Dec 13 2018 09:00

The NZ-only amendment to 60598.2.2, that gave is classifications for recessed luminaires, was a big step forward. Unfortunately the way it was produced & implemented lets the luminaire manufacturers off the hook, because it became the electrician's job to somehow know the heat withstand capability of the BTI. The mis-match between the figure used in the classification (eg CA 80) and the required temp withstand (90 degC) doesn't help. Nor does the fact that all this is hidden in the downlight Standard, and all "3000" tells us is what classes may / may not be installed. So most don't even know there's something they need to find out.

Most BTIs I've found a figure for have a"max service temp" of 80 degC. (Greenstuff polyester) has a max service temp of 160 degC degC. Bradford Gold has a "max service temp" of 350 degC. Pink batts info claims a nil clearance for CA rated lights; but I believe that info relates to the old type CA and pre-dates the newer CA-80 & CA - 135 classifications that have specific temp withstand requirements. The info I have doesn't give any actual temp figure, but one might reasonably assume it's OK. But for both these, while the glass fibres can withstand very high temp, the "binders" (ie glue) will fail at a much lower temp.

When "3000:2018" is finnaly cited, and we can start using the later set of classifications; the rules will be more straightforward and we should be able to just select & install based on the requirements within "3000".

Until then, we have to put up with the stupid system that makes us responsible for finding out whether the owner-chosen lights and the owner-chosen BTI are compatible.
   

Bilby42
Dec 13 2018 09:49

Great to have someone state some actual temps for BTI AlecK. The loose fill insulation in this case appears to be some sort of wool (looks like pink and white candy-floss).

The fittings are 12cm diameter SD100s, i.e the generic Superlux type of the early 2000s. Actually quite nice fittings, as they are easily released from ceiling by reaching up into the fitting and flicking a clip open.
   

SaintAlan
Dec 13 2018 11:47

I had a similar situation with the loose recycled-paper insulation. Messy stuff that gets everywhere.
We scooped out a clear area around each hole and inserted a strip of pink batts to form a 'dam' around the light fitting.
If I had to do the job again, Greenstuf would have been nicer to handle than Batts.
   

AlecK
Dec 13 2018 17:59

If it's coloured wool then basically it's sweepings from a woollen mill.
I believe it's good BTI if applied thickly enough (200 - 300 mm?); but I have no idea what the temp withstand might be
   

Elisse
Mar 01 2019 19:32

Hi you can visit this Company that called ABIS just click this link
https://www.abiselectronics.co.uk/collections/led-panels
   

oldspark
Mar 01 2019 22:02

Why not replace all fittings with LED's
   

daniel2
Mar 01 2019 22:24

I think this debate has done a full circle.

Very few LED fittings can be installed in or near loose filled insulation, as stated in the manufacturer's specs.

   

dlink
Mar 02 2019 14:51

daniel2
There is lots of LED downlights on the market that can be installed into ceilings with loose fill insulation.
   

daniel2
Mar 02 2019 17:58

Dlink, the various brands I've seen have stated in their instructions not to install in or near loose filled insulation (Insulfluff).

A way round it could be a suitable barrier.
   

Satobsat
Mar 02 2019 20:41

Suitable barrier? $2 dollar bucket with the bottom cut out, cut round the middle will make two barriers. Or a 150mm galv duct joiner if the clearances don't suit a plastic bucket. Silicone it down to the gib. Or make your own out of zintec sheet, tall enough it should prevent loose fill getting inside.
   

AlecK
Mar 03 2019 12:09

A $2 bucket is very unlikely to be "fire-resistant", nor to comply with either of the Standards cited, as required by 4.5.2.3.3 (e).

150 mm diameter may well not be enough. Depends on the SCI & SCB clearances for the particular luminaire, but if luminaire is eg 80 mm then there's only 35 gap between luminaire and barrier / BTI. Whereas the default SCI & SCB = 100 mm.

   

Satobsat
Mar 03 2019 14:19

I would have no issue installing an 85mm IC-F rated Led fitting with a section of a 260mm diameter plastic bucket. (obviously with the bottom removed) Most of these fittings have a 0mm SCB and HCB. I highly doubt the bucket would set on fire. I have seen old loose fill burnt black piled up on the back of two halogen lamps in a twin lamp fitting before now.

As for the duct joiner I'd be surprised to find any decent domestic Led fittings today that requires a SCB of more than 0mm.

Personally I'd use zintec sheet cut into 80mm by whatever strips, made into a ring with a couple of rivets. I've made my own up for a fraction of the price at whatever size required. If you want to be really pedantic you can even use fire rated sealant to stick them to the gib. Plus if the ceiling cavity is inaccessible you can preform and drill the strip feed it into the hole and fix it together, with screws or rivets, position it in place and clean any loose fill from inside its perimeter.

Alternatively you can say "no it's impossible" to the customer and walk away from the job leaving them with a much hotter halogen or incandescent down light with loose fill piled up against it.
   

AlecK
Mar 04 2019 08:54

Agree it depends on the SCI & SCB clearances for the particular luminaire (as I said earlier.
And that the metal version is a better option than the plastic bucket option - there's no way you can cal a typical plastic bucket "fire-resistant". Though I'd be using wider than 80 mm strips, given that the minimum depth you can expect would be 100mm (depth of joists); and I've seen blown wool installed at around 300 mm.

What isn't obvious in the rules of 2007 edition of 3000 - which we still have to work to - is that we have to know what temperature the BTI can withstand. That's because all the current NZ "downlight" classification (in AS/NZS 60598.2.2-2001 + AA) are based on the temp the BTI can withstand - 90 deg C for CA 80, and 150 deg c for CA 135. Even IC-F fittings are only rated for abutting / covering by BTI that can withstand constant 90 deg C.
So if the BTI is only good for 80, you can't abut or cover; even if it's an IC-F and the SCI is 0. My checks to date indicate that 80 deg C is all most forms of BTI are good for. The BTI temp withstand info can be hard to find; especially if you don't know the brand for existing BTI- and old stuff may never have been tested.

This issue won't go away when 2018 edition is cited; but at least it will be more obvious as the new classifications use the same number as the required temp withstand (eg CA 90 equiv to current CA 80; while the req'd temp withstand for a CA 135 is reduced to 135 down from 150).
While it's true the luminaires are getting better; therew's no indication that BTI has been changed to withstand higher temperatures; so we'll still need to check. And unless we can get good info on the BTI, we may have to just say "sorry, can't install those fittings you've already bought"

Another point is that even non-loose-fill BTI, eg batts / blankets of various materials, is not generally "fixed in position"; so barriers are called for. However staples / glue on the edge around the luminaire can be used to fix the BTI.