Month: January 2023

Types of asbestos cement roofing

Asbestos was used in roofing materials due to its fire-resistant and insulation qualities. There are different types of asbestos roofing products. Smaller roof tiles made from this material often look similar to slate roof tiles, and larger, corrugated sheets are used as cladding.

Whether large or small, these types of roofing tiles were made by combining asbestos fibres with Portland cement to create a highly durable material, which is why it can still be found in abundance today. Thousands of buildings across the UK still have roofs containing asbestos, but it’s only when there is damage that you would need to consider removal.

As a material, it can be tricky to remove, requiring a specialist asbestos removal company, and the building is usually sealed off and vacated. For safety reasons, there are strict disposal regulations that apply to asbestos. Removing asbestos also causes disruption for the building occupants and any business activities, which also have to be relocated.

Dealing with asbestos

An initial inspection will determine whether roof tiles or sheeting made of asbestos is damaged and needs replacing.

If there is no damage, then you have the following two options:

• Reclad the asbestos. One way to protect asbestos roof tiles and sheeting would be to overclad the asbestos to seal it inside. One of the main concerns with this approach is the fact this will add extra weight load to the roof, which could compromise the structural integrity of the building. Recladding is expensive, as effectively, you are fitting a new roof over an existing roof. This would also require planning permission.
• Repaint the asbestos. This is the cheaper and less disruptive option. A specialist protective asbestos roof coating is applied to the roof tiles or sheeting. The building occupants won’t need to relocate or be disturbed by any roofing construction work. It’s important, however, to choose the right product, consider the coverage rates, and follow the application guidelines to ensure you can obtain a guarantee for the work.

Asbestos roof coatings

Our Giromax® Roofcoat system has been designed to recoat asbestos cement roof sheets and cladding. This coating system sticks to the asbestos and seals in the dangerous fibres. It’s fully moisture tolerant, so you can apply during damp conditions, and it has a breathable membrane to prevent further water damage. Our Roofcoat system for asbestos cement sheets is also resilient to dirt and damage caused by birds.

Our asbestos roof coating seals and encapsulates the substrate, and can be used to treat and seal bolts, washers and fixings. The system contains a sealant, basecoat and topcoat. When applied correctly following our technical guidance, this product could extend the lifespan of the roof by another 20 years. The asbestos cement roof will need cleaning prior to application, which must be carried out according to current safety regulations.

For more information on asbestos or technical guidance on the application of our Giromax® Roofcoat system, please speak to the Giromax team or call 01455 558969 today.

 

About Matt

Matt has worked for Giromax since 2021. He’s gained a wealth of knowledge since starting his role and enjoys the ongoing learning. As a Technical Services Manager, he covers the Central Region, from Wales across to Suffolk. Before working for Giromax, Matt was a Business Development Manager in the telecoms industry. His broad range of retail and sales experience in client-facing roles has given him the ability to liaise with different types of people. This has proved essential when advising surveyors and contractors. Read more…

Let’s hear what Matt has to say about the seasonal challenges that have an impact on roofing work, as well as some insights on various projects…

Moisture-tolerant coating systems

Damp conditions

A common challenge for contractors is working to extremely tight timescales for a specified coating system. In autumn 2021, we worked on a dilapidations project in Birmingham with a 10,000 sq. m roof. A silicone system had been specified for the job, but this can only be applied in dry conditions. As a result, the timescale was unrealistic and not achievable.

As Giromax products are moisture tolerant, one of our coating systems was recommended. Being able to apply a coating in damp conditions reduces the amount of downtime for contractors. Most silicone systems require two coats, while many of our products are one-coat systems, which also saves time. The contractor was able to work more efficiently, achieving the timescales required with less disruptions due to weather conditions.

Applying coatings during a heatwave

Hot conditions

When the ambient weather is above 25 degrees, we always advise checking the temperature of the substrate. We have recently been working on a largescale project for a national organisation with multiple hubs, with a collective roof span of 30,000 sq. m (20,000 has been completed so far). Application advice has been the key to success for this job. The project started in April with one aspect completed in August, during the 2022 heatwave.

Due to the high summer temperatures, work had to be carried out early in the morning, with contractors up at 5am to be onsite and applying the coating from 7am. In ambient temperatures of 30 degrees, the substrate can rise to 50 degrees, which makes it impossible to apply a roof coating. The ideal temperature range for application of a roof coating system is over 5 degrees and below 35 degrees. Despite a few small delays caused by the weather, the contractor was able to meet the scope of works and required deadlines.

Close up inspections

All weather conditions

A forthcoming project happening over the winter months and early spring will have to take the changing weather conditions into account. The building is located in Bristol and the roof span is 13,000 sq. m. Our cut edge corrosion treatment has been applied previously, but now the whole roof needs coating. In this instance, the surface will need to be prepared correctly, which will then be followed by a basecoat, sealant and topcoat.

As roof coating systems cannot be applied below 5 degrees or in heavy rain, the cold wintry weather is likely to impact this project. Matt has already surveyed the roof, and once the scaffolding goes up, he will return to the site in January to re-inspect the roof. This enables him to get a close-up view of the roof, which cannot be achieved using a cherry picker or drone. Over the project duration, Matt will do 10 or more site visits before the work is completed.

Coverage rates for coatings

Matt’s role as a Technical Services Manager is very varied and includes advising on snagging, which can occur when the coverage rates have not been checked. He also stresses the importance of correct application.

Preparation is paramount to the success of a job, and if not done correctly, this will cause issues. Operatives also need to know the coverage rates for coatings, which are listed on each specification and involves using a wet film gauge. This helps to minimise snagging, which is time-consuming as you then need to key, clean and reapply.

We’re proud of our hardworking and multiskilled team of Technical Services Managers, who are always on-hand to provide technical advice and recommendations. As the original leader in the roof coating market, we continuously test, develop and improve our products.

If you need technical advice on preparation or application, please speak to the Giromax team or call 01455 558969.