The walls of t he Lisbon Ismaili Centre take the form of a composite lattice of granite members and steel tubes: for the large volume of the Prayer Hall, the lattice is doubled and braced by stainless-steel tie rods, while the limestone domical vaults of its roof are supported on similar tubular trusses.
Rather like Viollet-le-Duc, whose designs for iron tension-strutted masonry domes share an unexpected similarity with the domical vaults in the Lisbon Ismaili Centre and the New Delhi Parliamentary Library (as pointed out by Peter Davey in AR October 2002), Rewal's passage a l'acte sometimes lacks a certain lightness of touch.