No hiding place

// the building envelope

HA Magazine considers a safe, modern and high performance alternative to corrugated asbestos sheeting.

In every respect from fire protection to non-slip flooring, and from thermo-static mixing valves to toughened glass, the country’s social housing stock has been made far safer than at any time in the past. Yet a menace still lurks in much of the older, pre-eighties stock which continues to take hundreds, possibly thousands of lives each year.

Once considered a wonder product for being inert, fire-proof, weather resistant and offering reinforcement to board products, asbestos was used everywhere in construction from roofing products to pipe lagging and interior decorative finishes; while it was even fashioned into tanks for airing cupboards. Painstaking refurbishment projects down the years have witnessed careful removal of the cancer causing material from the living environment, but the fibres can lie dormant in people’s lungs or pleural cavities for years before the symptoms of asbestosis start to exhibit themselves.

And threateningly, asbestos remains commonplace in one particular area of our built environment! 

The old corrugated roofs to garages, lean-to sheds and other assorted, mainly single storey buildings are largely still in place from the days before the industry and its regulators woke up to the reality of asbestos dust. Undisturbed it poses little threat, but as the sheets begin to break down, or if a resident decides to scrape the moss and other build-up of dirt off them, the deadly fibres can be inhaled. 

Happily, however, Cembrit is offering a ready solution for the replacement of old, potentially highly dangerous asbestos, or equally superannuated galvanized steel sheeting, through the availability of its B5 product.

Crucially B5 is made available in imperial sizes up to ten foot six, while the sheets are some 40 per cent wider than their three inch predecessors in order to give better coverage and reduce installation time. They are fixed in a similar manner to the originals with a coarse threaded screw and washer; while they are produced from a blend of Portland cement, blended cellulose as well as synthetic fibres and inert fillers.  B5 is manufactured in accordance with BS EN 494:2004 and under an ISO 9001 quality controlled process. 

Ged Ferris, The UK Marketing Manager for Cembrit, commented: “Essentially we view it as a high performance alternative to the traditional three-inch asbestos or galvanised metal sheeting which is seen not just on garage roofs, but sheds, coal bunkers and larger, mainly single storey structures like community halls. We are offering a better type of curve which can be laid at angles down to 10 degrees and still clear water more effectively.

“Our profile is deeper which improves the discharge capacity, while it is available in either a painted or unpainted finish. With a primer and then the factory applied top coat, B5 offers a far better finish than the traditional alternatives. The paint finish is backed by a ten-year guarantee while the sheets themselves have a minimum 30 year lifespan.   

“It has been employed on a number of ‘architectural projects’ including a residential property in South London’s Lordship Lane which featured on a recent Grand Design’s programme.”

The possible colour options available under the B5 brand include Tile Red and Spanish Red as well as Laurel Green, and Mocha.  Blue/Black, Black and unpainted natural grey complete the choice for the roofing specifier.

View The Latest Issue