ECN Forum Forums Code Related Discussion Building Codes for Electricians Cans in rated ceilings

I got a ballpark of $45 each from the manufacturer. I'm sure shipping and other variables apply.

For any product to qualify for use in a rated ceiling, it has to pass a fire test...it is actually installed in a ceiling, and the assebmly is exposed to a defined fire; the results must pass the same criteria as the ceiling passed without the product.
As you might guess, it is essential that the product be installed as specified by the manufacturer, and not altered. The limitations of the rating agency need also be obeyed.

The fire tests are quite realistic; a very large piece of ceiling is constructed (appx 20 ft. sq), and is subjected to an enormous, controlled natural gas fire for a specific time. Temperatures are monitored on the "unexposed" face; for it will not do much good if the outside itself gets hot enough to light a new fire! Nor will it help if the structure is weakened to the point of collapse.

Here in NJ there is an energy code. You need "Air tight" cans to prevent heat loss from going into an unheated space. You also need "Fire Rated" cans if you are in a garage or ceiling that needs the fire rating. The 2 types of cans are very different and cost differently too. You can install pices of gypsum around the can to make it fire rating or buy the expensive fire rated can for use in the garage.

As far as I know, the reference John S. made to the fire test has never been performed on these drywall boxes that are built above recessed cans. Just one of those things we've always done.

Please correct me if I'm wrong here!!!!

Hey Ryan,
Progress makes a fire rated recessed light. I think its called a FIREBOX.

pHIL

That test is based on the standard time temperature curve and actual structure fires are quite a bit hotter. The curve was developed from measurements of actual fires in ordinary occupancies (masonry bearing walls with wood joists and rafters). The testing was done in the days prior to the use of large amounts of synthetic materials in the built environment. The synthetic materials cause the fires to develop faster and they give up their BTUs much more quickly. So even though the synthetics average fewer BTUs per pound by burning so much more quickly they cause a much sharper temperature rise. The standard time temperature curve is still useful in comparing materials and techniques to each other but it no longer reflects the stresses that todays built environment subjects the materials to.

The only issue I see with these fixtures is that they are extreemly limited by the joist spacing available. I've run across everything from 12" on center to 24" on center and everything between. Good idea though...

Guess the market is evolving.
Needed a 1 hour fire rating for some IC rated lights and inspector would't approve the ez barriers sinc ethey weren't UL classified so he recommended this new (?) product.
http://www.tenmat-us.com/
Worked out nice.

Whats the problem with a taped sheetrock box? Good enough for a ceiling but not a light?
I always thought the airtite,IC cans were fire rated.
But now they have those double canned cans.

Were they put on before the insulation? Is there a solution for old work? The insurance co. will only say that the "slit" was more than 1". What is the size of the wire access? those vent holes, does'nt that negate the fire rating?

"trust us, your in good hands"

Well IC rated doesn't stand for fire rated. There is an interesting article about that topic in the January issue of Electrical Contracting Products.

The vent holes were also one of my concerns, but they told me that the tents are made of intumesent material that will expand in case of a fire and close all openings.