Corrugated Cement Sheets

The word ‘Asbestos’ strikes terror to many clients’ hearts – and the separate garage roof is often a principal culprit. Roofs covered with corrugated cement sheets are very likely to contain white asbestos. The corrugations may be “Big 6” or “Little 3”, which refers to the size of the gap between the ridges -in inches ! So they date from pre-metric times – but  asbestos has been used in building materials since the early twentieth century.

These are normally found on a 1960’s concrete sectional type garage.  These are simply constructed from posts into which the concrete panels are slotted, forming the walls. Then  metal trusses form the support for the corrugated sheet asbestos roofing. The Health and Safety Executive have a work sheet detailing how to safely remove asbestos cement; this will give you an idea of what is involved.

What condition are they in?

Asbestos sheets are not necessarily ‘dangerous’ if they are in good condition. They were expected to have a life span of around 25 years. However many of the sheets have easily doubled their expected life span and are still going strong. If the sheets are in sound condition, then sealing them properly may be a viable course of action rather than removing them. Remember surveyors do pick up on corrugated sheeting if you are selling a property so you would need evidence that the sheets had been treated correctly.

What about removing them?

Such work has to be undertaken by a specialist contractor. While there are several types of asbestos, most companies don’t even test corrugated sheets of this type on a garage or shed. They simply remove them presuming they contain white asbestos.

When pricing for removal, don’t forget to allow for replacement of the roof covering with new sheeting! There are boards available that are similar in appearance but stamped “NA” meaning no asbestos. You can use the lightweight black bitumen based Corolux style sheeting or PVC sheets, although these will have a reduced life span.

What about other asbestos hazards?

Garages may also contain blue or brown asbestos in their make up – or

there may be sheets of boarding left lying around, normally leaning against a garage and hidden by undergrowth. We have come across many situations where the garage structure is not presumed to contain asbestos; however when we have visited the site, we have found numerous boards of differing ages. These have been collected and stored in corners as they “may come in handy at some point”.These however should be tested as they can be the more dangerous blue and brown types and only testing will identify it. If blue or brown asbestos is found to be present, this will increase the cost of removal.

We have also come across situations in either sheds or garages where the material used is clearly not wooden fibreboard, orientated strand board or chipboard. This is obvious from its brown colour or textured surface finish. Then it should be presumed to contain asbestos and again should be tested.