Haddonstone – a material for all purposes and climates
Housebuilders need to think ahead and use materials that will withstand Britain’s changing climate and last into the future. As global temperatures begin to rise, the construction industry is responding by increasing the ‘thermal mass’ of buildings. This is because buildings with high thermal mass (or capacity) are slower to respond to outside temperature changes, meaning that they stay cool in hot weather, without the need to fit air conditioning.
Although high thermal mass capacity buildings take longer to heat up during winter months, once they have, they stay warmer for longer than lower capacity structures. With rising fuel bills, the ability of high thermal mass buildings to keep heat in during the winter becomes more important.
High thermal mass is most simply achieved by building thicker walls from heavyweight, dense materials, and adding smaller windows to reduce the amount of heat entering or escaping from the building. Haddonstone is a blend of crushed limestone, cement and binders and is available in a dry-cast and wet-cast (TecStone) mix. The material is heavy and dense - perfect for increasing the ‘thermal mass’ of buildings.
At the same time as the thermal mass trend gains momentum, increasingly stringent health and safety guidelines are forcing developers to look for building materials which are as thin and light as possible.
As well as producing a heavyweight material, the company has also introduced TecLite, a thinner and lighter version of Haddonstone. Using GRC technology and thin wall construction, TecLite is as strong and versatile as standard Haddonstone.
Haddonstone has shown itself to be at the forefront of technology, as both materials look almost identical and can therefore be used on the same project. For example, standard Haddonstone could be used at ground and first floor level on buildings, with TecLite used at parapet or roof level to reduce the dangers of working with heavy materials at height.
As an island, Britain is particularly at risk of a further effect of global warming – rising sea levels. Large parts of the country could potentially be flooded in the future, leaving areas which are currently inland exposed to the potentially damaging effects of saltwater and wind from the sea.
Haddonstone is also ideal in these new, challenging environments, having passed stringent tests conducted at the world-renowned BRE (Building Research Establishment) laboratories. The material was subjected to rigorous salt crystallisation tests, designed to measure the level of erosion caused by exposure to salt. Haddonstone’s cast stone material sailed through the tests, and in fact was shown to perform better than many “natural” stones.
BRE also conducted water absorption tests on both the dry–cast Haddonstone and wet–cast TecStone materials. Both versions also passed these tests, meaning that they would easily cope with a stormier and wetter climate.
TecStone, in particular, has a low water absorption rating, and because of this it weathers, or ages, extremely slowly. This makes it ideal for projects where a bright, unweathered look is important – particularly contemporary architectural design.
With the Haddonstone dry-cast mix the surface acquires a patina, and weathers more easily. This is particularly useful where Haddonstone is required to quickly blend with existing “natural” stonework, for example on restoration projects.
The structure of the stone is not affected by this weathering – in fact it continues to increase in strength for some time after production. But even when it is first produced, Haddonstone satisfies stringent British and UKCSA standards. The minimum cube compressive strength required to satisfy UK standards is 25MPa, whereas Haddonstone easily reaches 35MPa, and wet cast TecStone surpasses 45MPa.
As well as being a proven success in warmer climates, TecStone has also passed the Canadian Freeze-Thaw test, meaning that it can be used in colder environments. To date Haddonstone’s cast stone materials have been successfully used for major projects in countries as diverse as Norway, Russia, Singapore and Japan.
Haddonstone is the UK’s leading manufacturer of cast stone architectural features. The standard collection ranges from copings, window and door surrounds and quoins to balustrading, columns and porticos. The company is also able to create custom made designs to almost any shape or size, from either architects’ drawings or as copies of originals.