CROSS LAMINATED TIMBER (CLT) BUILDINGS
Cross Laminated Timber (CLT) Buildings in UK
Yesterday, I went and saw three cross laminated timber buildings in London. CLT are made by gluing the timber planks together in layers at right angles to each other using non-toxic adhesive. Generally, there will be 3, 5 or 7 layers of timber each one approximately 22mm thick.
I met Andrew Waugh of Waugh Thistleton Architects who told that everything will have to be planned well so early. According to him, the number of trees which will have to be cut is four per person.
It is becoming a slow trend and already there are 400 buildings now. They are importing the CLT from a factory in Austria. I understand that there are factories in Sweden, Germany, US and Canada. Two factories are going to be established in UK as well.
The buildings as I saw is wholly built in timber. The first one I saw was a 9 storied building which was the tallest structure built fully in timber at that time in the world. Now Waugh Thistleton Architects themselves are building a 25 storied building now. The lift shaft, the floors, the staircase, the walls the facade all are built in timber. The first building, "Stadthaus, 24, Murray Grove" is an apartment building and it took 11 lorry loads to bring the entire timber. The concrete structure would have taken 4 times the load. The building was started in 2008 and finished in 2008. There were four carpenters who assembled the entire building in 27 days. The dimensions are very precise and has very good thermal and acoustic properties. The fire resistance of the buildings is also very high.
The CLT is made out of pine timber. The panels are manufactured in long sheets and they are complete with cut outs for windows, doors and all the services. The different panels are jointed together using 75 mm GI brackets. When we think that more than 15% of the greenhouse gas emissions are from concrete and steel, while this makes the building carbon negative. According to Waugh, it will take 29 years of the building use with the services to make it zero carbon. So these buildings are very eco-friendly. Use more and more timber in buildings to save the environment. The time is saved in construction and the money in foundation because of the light weight.
I think it is time that we introduce something like this in India. Timber is definitely the future building material because it is the only thing which can be grown.