- What feels like a long, long time ago now,
we produce some content explaining the issues
surrounding fire rated ceilings.
We busted some myths
and clarified some common misunderstandings.
At the time, the NHBC required that
if recessed lights were being installed
into ceilings made with engineer's joists
like these ones from StairCraft,
then those fittings had to have been tested
against the specific joist manufacturer
they were being used in conjunction with.
This sent a lot of lighting manufacturers
into a bit of a tailspin
as they dashed to get their fittings tested
in huge costly facilities that mocked up an entire room
and set it on fire.
As there are at least
five major manufacturers of engineered joists
and each test cost around 20,000 pounds,
this was quite a big deal.
Not to mention the huge waiting times
on suddenly overwhelmed test facilities.
Then electricians needed to wrap their heads around
the idea that it very much did matter
what fittings they installed,
even though they weren't responsible
for the joist type used.
And that it was their responsibility
to make sure the fittings were acceptable.
And now we have a sequel to those events
and it's good news
for lighting manufacturers and electricians alike
as StairCraft I-Joists now feature
in the Robust Floor Construction Pattern Book,
published by the Structural Timber Association.
This document is peer reviewed by BRE
and supported by the NHBC
and means that a fire rated ceiling and floor
built according to the details in this book
goes beyond the fundamental requirements
of the building regulations
in offering resistance to the passage of fire.
In fact, on average,
a floor made with StairCraft joists
will be 30% safer than the fire regulation requirement,
meaning that if 30 minutes escape time is needed,
it will offer a further nine minutes
for escape to people using the floor.
So why do you as an electrician care about this?
Well, looking in the patent book,
you can see here there's a row marked Downlighters
and it states that
"a recessed fitting may be used if it is
tested as part of an REI30 floor assembly
to BS EN 13065 dash 2,
or as a service penetration with EI30 classification
to BS EN 13501 dash 3
for the application or verified by manufacturer's test data
for the application."
This means it's now a lot easier
for lighting manufacturers to prove
their recessed downlights can be used
in conjunction with StairCraft's I-Joists.
Instead of paying for a huge test such as this one,
they only need to pass a small scale furnace test
at a fraction of the cost to prove their suitability.
They then get added to a list
published by the Structural Timber Association
and can be used in ceilings
constructed using StairCraft I-Joists
that follow the guidance from the patent book.
This opens up the options considerably.
And in fact, looking at the list,
you may well find that the fittings you regularly use
are already cleared for use.
You can see the major players represented there.
Specific fittings from Ansell, Collingwood,
JCC, Luceco and Robus
are all approved for use in connection with this.
There is one important detail here
that needs to be adhered to though,
and that is there's a limit
to the amount of fittings you can put into a ceiling
constructed in this way.
You must install no more than one fitting
per square meter of ceiling,
and each fitting must be 600 millimeters away
from any other fitting.
However, StairCraft are not ones to sit on their laurels.
They're always looking for ways to improve and do better.
And to that end,
they've submitted their flooring
using their I-Joists for testing
with no downlights installed at all.
Just holes where lights could be, and guess what?
The floors pass the half hour test rating
even in these extreme circumstances.
Just incredible, really.
Now, this last piece of information
doesn't mean that you can just start punching holes anywhere
and use any old fitting.
But it is encouraging to know
that a StairCraft I-Joist ceiling
is a robust piece of construction
that will hold up for the necessary periods
if the worst should happen in a property.
For more information on StairCraft I-Joists,
download the StairCraft Install app
or visit their website, staircraftgroup.com
and click on the resource center button to find out more.
Or take a look at this video here
on recessed downlights.
Thank you very much for watching.