Many of the questions we receive concern asbestos roofing problems and as a consequence, we are now widely considered to be the UK’s leading authority on asbestos roofing issues.
According to the Land Registry, an incredible 55% of all industrial type properties in the UK have an asbestos cement roof and 75% of all asbestos roofs ever installed are still in-situ today.
It’s easy to spot an asbestos roof from the contoured outline and grey or buff 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.
However, with age comes deterioration 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, though may appear soiled and mossy.
Extreme caution should therefore be applied when walking on an asbestos cement roof, with professional access equipment 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.
However, it might not be economically viable to replace a roof that is in reasonable condition and in these cases, a specialist asbestos roof coating should be considered as this will prolong the life of the roof and cost substantially less than a new roof.
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 for this purpose and the work is best carried out by a competent contractor.
Most Asbestos cement products are not currently licensed, so you do not need a licensed asbestos contractor to remove or work on the material. The works may however, still be notifiable to the HSE under the “non-licensed, notifiable” classification.
You will however, still need to dispose of any asbestos containing material 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.
If you think you have these paper liners present in your building, arrange a roof survey. A leak or fire can turn into a clean-up operation costing tens (or hundreds) of thousands of pounds.
Another common way of lining asbestos cement roofs was to use an internal asbestos cement liner panel.
These are flatter than the external panels and usually present a low risk of contamination, unless they are broken of course.
In some buildings however, we have discovered lining panels made from Amosite (brown asbestos) and others that contain both Amosite and Crocidolite (blue asbestos). Some roofs are even sprayed with blue asbestos lagging.
These materials should not be interfered with under any circumstances and our advice is generally to have them removed at the earliest possibility, as the risk of failure and building contamination is quite high.
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 provide assistance by telephone without charge.