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Posted By Topic: Downlights with loose fill insulation

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?


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"

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.

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.


Dec 12 2018 23:38

Here is a modern loose fill insulation product.

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....

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.

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!

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.

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.

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.

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