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Rat Trap Bond for Walls
Thursday 2 November 2006, by
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The rat trap bond (RTB) was first introduced by eminent architect Laurie Baker in India and supported by HUDCO.
In the RTB bricks are placed on edge in 1:6 cement mortar as shown in the picture. With this technique there is reduction in cost of the wall by 25% as with conventional English bond (9’’thk wall) 350 bricks are required per cu. m whereas in Rat-trap bond only 280 bricks are required and also the reduced number of joints reduces the mortar consumption. No plastering of the outside face is required and the wall usually is quite aesthetically pleasing and the air gaps created within the wall help make the house thermally comfortable. In summer the temperature inside the house is usually atleast 5 degrees lower that the outside ambient temperature and vice versa in winter.
Thus the main advantages of using Rat trap bond are:
· Reduction in cost of the wall by 25%.
· The reduction in number of joints, reduces mortar.
· 25% less dead weight, 18% savings in bricks and 54% savings in cement mortar
· Thermally comfortable & Aesthetically pleasing.