While listening to a web stream of a radio station 4KQ from Australia (Internet DX?) they had a news story about badly installed thermal house foil faced insulation. Seems that the installers used staple guns to hold the insulation in place, and sometimes managed to put staples thru electrical cables of the sort similar to Romex. Some houses had "80 volts of electricity on the foil" according to the news reports, and it seems this has caused a few house fires. Seems that there was a government funded rebate program to help pay for the insulation and its installation.
Yeah, That happens quite a bit down here. Some people seem to forget (or ignore) the fact that aluminium foil is an electrical conductor. I remember a few years back, going to one of the local scout dens where a plumber had recieved a 230V shock while climbing under the floor through the man-hole and touched the foil that was live at full mains voltage.
It took ages to find the fault, because the staple had only pierced the phase wire in the cable.
BTW, this sort of insulation is only used in the under-floor area of buildings, not up in the roof void.
#192889 - 03/09/1001:13 AMRe: Bad installation of thermal insulation Australia
According to a newscast over the same internet stream radio station 4KQ, seems that blame is being aimed at the "president" (prime minister? never did understand the difference) for this program's problems. Does the installation of insulation by a contractor require a permit and inspection? By the towns building dept inspector? If so, it shouldn't have mattered who paid for the jobs, if they were done so poorly the inspector should have failed the installation. Here in NJ in the USA, the law is that the contractor doesn't get final payment until all inspections have been passed by the building/electrical/plumbing inspector.
#192891 - 03/09/1010:34 AMRe: Bad installation of thermal insulation Australia
Anyone out there considering fitting this stuff, don't bother, it's next to useless. Quite apart from masking insect, plumbing, electrical and rot problems, it stops working as soon as dew forms on it, which it will unless sealed in both sides with polythene membranes. It won't work without defined casings both sides to maintain an air gap of about an inch. It also fails as soon as it gets dusty, or spiders get near it. And I found, from personal scientific tests on a heated oil storage cabinet that even a new clean 13-leaf version was less insulating than 2" of styrofoam. It failed to get official Gummint NF approval in France due to the above problems. Stick with foam or Rockwool. Much cheaper and they work!
If one had to devise a scientific experiment to determine the insulating qualities of a material, what better than a suspended hollow cube of the material, fitted with a known wattage electrical heater inside, with thermometers inside and out. A bit of simple math would quickly establish an R value, based on the heat loss. And if you visit a box store, the R [or U ] values are printed on all the insulating products. Except on the foil where no such values are ever quoted! The reason? The 'experiment' to determine the wild claims often made for foil insulation is this. An infra red lamp is set up pointing at a screen of the foil. Temperatures measured each side of the screen are compared to various thicknesses of other insulation. "Hey presto!", they cry, "Our product is the same as 10" of Rockwool!" - failing to point out that it's also equivalent to a sheet of newspaper.
I remember as a kid, back in the 60's when my father built our house he used fiberglass material intended for freezers between ferring strips (masonry outside walls) and some sort of foil lined tar paper over the fiberglass, just behind the sheetrock. I think it's just to create a vapor barrier, and not insulation. That's all it would be anyway.
I think NASA uses stuff similar to this on space probes and satellites, but in space there's no convection (no air) and it's out in the open to reflect sunlight. Not hidden inside.
Now I see why the Aussie politician should be criticized, as this foil insulation is a poor choice for the job.
#192907 - 03/10/1005:37 AMRe: Bad installation of thermal insulation Australia
WA2ISE, Foil insulation has been installed in New Zealand here for ages, the only difference being, it was always installed underneath the particle-board flooring, on top of flooring joists. The foil was installed during the construction of the house, in that it was allowed to have an air-gap between joists.
This idiotic idea of "lets throw some aluminium foil up in the roof" has to stop. Fibre-glass batts are made for this purpose and no amount of "green lobbying" to the contrary is ever going to make this a reality.
Let's add into the equation, a few years later when Harry Homeowner, decides he might like some new down-lights in his lounge or kitchen, what he will do is either chop bits out of the foil or will simply ignore the foil and install the lights anyway (under the foil). Either way, this is going to end in tears.
Government departments and the green movement need to be held accountable for rash statements about the effectiveness of foil as an insulating medium.
If it was my house, there'd be no way I'd even consider foil as insulation in a roof void. Mainly because, if there is a fire in your roof, the first thing that would be removed by any fire brigade, would be the foil, in an attempt to get nearer the seat of the fire.
#192940 - 03/11/1012:58 AMRe: Bad installation of thermal insulation Australia
This has been a major embarrassment to the govt, especially given that it's an election year. Hundreds of fly by night backyard companies sprung up out of nowhere when the rebates were announced. One story I heard was of an installer getting his kids to go into the roof to put down the insulation while he sat outside. Apparently the qualifications required were pretty much nil and there were no inspections afterwards. Then there was a couple of installers who died of heatstroke putting in batts in the middle of summer. Of late the live foil issue has surfaced and now millions will be spent inspection all such installations and fitting earth leakage breakers at those houses. When someone goes around willy nilly with a staple gun in a roof not knowing what's under the foil, it's bound to penetrate the TPS cable. The results were exactly as predicted. Personally, I didn't take 'advantage' of the scheme as my house is already insulated with fibreglass batts, and I prefer to do any work on my house myself.