<b><b>Changes to the way we build houses could prove to be a boost for the cement market. Allison Heller reports</b></b><br><b>Cement has a strong hold on the mortar market, and according to the British Cement Association (BCA) just under a million tonnes of it was produced last year for this purpose alone. But the traditional hydraulic lime-based mortar niche is growing.</b><br><b><b>Mortars</b></b><br> Lime-based mortar is preferred by some for its flexibility and strength, which eliminates the need for expansion joints. It is increasingly used in the conservation of historic buildings to provide visual continuity where the original mortar would have been lime-based, and for developments where a historic appearance is desired.<p></p><p>There are also hybrid mortars, such as Buxton Lime Industries&amp;’ Limebond, which is a pre-mixed lime based masonry cement, approved by the NHBC and English Heritage. It has recently been used at a Victorian conversion and development of a number of dwellings on the site of the former Herne Hospital outside Canterbury. </p><p> &amp;“Limebond has proved popular with the brickwork subcontractor who finds it is nice and &amp;‘fatty&amp;’ on the trowel and therefore easy to use,&amp;” says Colin Lowe, site manager with developer, Saxon.</p><p>Chief buyer, Mark Thompson, had similar praise: &amp;“Limebond has …