Brick includes brick clad timber frame and rendered blockwork. A brick house partly clad in timber could also be classed under brick.
Stone includes rubble wall, ashlar, knapped flint and the like. No allowance has been made for carved work.
Timber construction, such as log cabins or timber framed and clad houses, are not covered by the calculator.
Where a house has been constructed using a system, such as pre-cast concrete panels, it is most likely that it would be rebuilt using brick or rendered blockwork construction. Provided that it would be possible to rebuild the house in brick and that the layout is not unusual for an equivalent house in standard construction then the rebuilding cost for brick walls can be taken.