Protecting our Heritage

The material has managed to maintain its place as the waterproofing material of choice throughout the intervening years. With a reputation as a traditional material, it is hardly surprising to find that Buckingham Palace, the Houses of Parliament and the Bank of England all have mastic asphalt roofs that have lasted for more than 100 years.

Authentic materials for the conservation of these buildings and structures must not only retain the character, but also prove long-lasting and highly effective. Mastic asphalt, whilst a traditional waterproofing material that was first patented in 1837, offers durability and wear resistance far beyond modern alternatives which is why it is so frequently specified for refurbishment projects by the National Trust and English Heritage, as well as other public and private owners of prestigious buildings.

Testament to the longevity of mastic asphalt is Britain’s most famous home, Buckingham Palace, which features mastic asphalt on its rooftops.

Mastic asphalt has kept the Royal household dry for over a century. A stone’s throw away on the Thames, the Houses of Parliament’s complex and elegant roofs have also been waterproofed with mastic asphalt.

Mastic asphalt has also been used on the iconic 125-year old Tower Bridge, the Grade I listed river gateway into London. The bridge had previously been protected with mastic asphalt and it had performed so well that it was decided to specify it again. One of the biggest challenges was to strip back the existing mastic asphalt and replace it whilst minimizing disruption to pedestrians and river traffic.

With the refurbishment carried out while the bridge was still open to pedestrians and ships, there were many restrictions with plant and machinery due to weight limits. A total of 800 tonnes of material had to be broken out and reinstated, all with limited access whilst at the same time ensuring millions of pounds worth of bridge lifting machinery was kept dry and safe.

What makes mastic asphalt so appealing for heritage projects, from local restorations to maintaining internationally renowned buildings, is its suitability, performance and appearance, which is in keeping with the stonework of these prestigious structures. More faithful to tradition than virtually any other roofing system, modern polymer modified mastic asphalt provides a far more effective waterproofing material.

Although mastic asphalt is renowned for use on heritage buildings, it is equally likely to be found on modern buildings, especially town centre and large shopping centre developments built using traditional construction methods. Both Bluewater in Kent and Birmingham’s Bullring have mastic asphalt roofs.