An exciting blend of lime and recycled glass to make plasters, renders and mortars
Lime plasters have been used for over 12,000 years; no plaster has performed better in old, solid wall construction buildings. The product designers concern at Ty-Mawr for the environment however, led them to look at improving the green credentials of this ancient material, the result was glaster®.
Glaster® is an exciting blend of lime (binder) and recycled glass (aggregate) to make plasters, renders and mortars.
These products are ideal for use in old buildings as the use of the traditional lime binder means that they benefit from being vapour permeable (to manage moisture and hence regulate humidity), are relatively ‘soft' allowing the building to continue to move and flex (which they are designed to do) and can be recycled at the end of its useful life.
They are also a perfect choice in more sustainable new builds where low impact materials are demanded. It is ‘greener' because it uses a binder that absorbs carbon dioxide when curing and is burnt at a lower temperature than cement. Environmental benefits of the recycled glass include reducing the extraction of a virgin raw material (160.5 million tonnes are extracted annually in the UK for construction purposes, 14.5 million tonnes are marine dredged) with environmental implications, it also reduces the volume of waste sent to landfill and saves the energy and natural resources required to make new glass.
Finally, these products can be used simply to provide a surface finish with a difference in any building - as well as being able to add different pigments to give a ‘coloured' finish, the glass can be revealed to ‘glisten' in the light.
Glaster® has undergone testing by the Building Research Establishment (BRE) against a number of standards for use as both a plaster/render as well as a mortar. These tests demonstrate some advantages over traditional lime plasters, with the glass acting as a pozzolan and thus aiding the speed of set as well as the ultimate strength.
The product is robust enough not to require a paint finish, the self-coloured range is therefore extremely popular externally. For example, it was used in the grounds of Upton Castle in West Wales where the ‘orange' pigmented render was specified to compliment the colours in the natural landscape.
The Duchy of Cornwall chose glaster® for the internal finish of the Great Hall at Llwynywermod where the quality of finish as well as the environmental credentials were of paramount importance. Howies Organic Clothing and Neal's Yard Herbal Remedies also chose these products for their London shops for the same reasons whilst ‘Wahaca' used the internal finish in their Mexican restaurants for aesthetics reasons as well.
The team at Ty-Mawr, spend a great deal of time raising awareness and delivering support for architects in specifying this new, innovative material by delivering training days (at their own training centre or on the client site) as well as delivering RIBA accredited CPDs across the UK.