Asbestos Roofing
Many of the questions we receive concern
asbestos roofing.
It's easy to spot an asbestos roof from the
crinkly outline and grey colour. The roof profiles are
constructed from asbestos cement - most typically
Chrysotile (white) asbestos.
Cement based products like roofing and cladding
sheets are fairly low risk, because the asbestos is
contained within the cement to add strength and water
resistance.
With age comes deterioration though and the
panels can become porous and be prone to
leaks.
This creates additional problems because as they
get porous, they are also weakened considerably, yet show
little sign of this from the outside.
Extreme caution should therefore be applied when
walking on an asbestos cement roof, with crawling boards
being employed wherever possible.
When broken, an asbestos cement panel can
release fibres and therefore, if working on a panel, it
is strongly advised that breathing masks be worn to
protect the lungs from asbestos fibres.
One of the biggest dangers comes with fire,
because although they don't burn, the panels can explode
in extreme heat and shower the surrounding area with
invisible asbestos fibres.
If your asbestos roof is in a poor state of
repair, it is advisable to replace it with an alternative
material, rather than trying to patch it with other
products that don't quite match the outline of the
original.
Asbestos Roofs - The Inside
The main consideration with an asbestos cement
roof is what is underneath it, on the inside of the
building.
If the roof is unsealed and you can see the
asbestos cement profile, it's good health and safety
practice to have this painted to further encapsulate the
asbestos materials. A specialist asbestos paint is
available and the work is best carried out by a
contractor.
Asbestos cement is not currently licensed (as of
November 2004), so you do not need a registered asbestos
contractor to remove or work on the material. This may
change sometime in the future.
You will however, need to dispose of the
asbestos properly as the material itself is a considered
to be hazardous waste.
In many cases, the inside of an asbestos cement
roof will be lined with plasterboard or fibreboard
panels.
During our surveys, we have discovered many
instances where the paper lining on these boards has been
100% Chrysotile paper.
These liners, if disturbed can present a risk to
health. If the roof is dry and in a stable condition,
there should be no problem, but if the roof is leaking,
the fibre boards tend to sag and break, falling into the
building below, often releasing asbestos fibres into the
air.
Another common way of lining asbestos cement
roofs was to use an internal asbestos cement panel. These
are flatter than the external panels and usually present
on a low risk of contamination - for example when they
are broken.
In some buildings however, we have discovered
lining panels made from Amosite (brown asbestos) and
others that contain both Amosite and Crocidolite (blue
asbestos).
These materials should not be interfered with
under any circumstances and our advice is generally to
have them removed at the earliest possibility.
If you suspect that your roof liners could
contain asbestos and are concerned about health and
safety issues, please contact us on 0121 711 7110.
We will be pleased to offer advice by telephone without
charge.
© Energy
& Environmental Surveys Ltd - Asbestos
Roofing
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