This question refers to the materials of which the outer walls of the housing unit are made. Although this may be completed from your own observation, you may in some instances need to enquire from the householder whether or not the walls are reinforced.

Concrete and blocks: Include here walls of concrete blocks with steel reinforcement but not nogging. Include units made of "prefabricated" material in this category.

Stone and brick: This applies where walls are made of stone or of red bricks, made by a kiln-burning process.

Nog: include here units where the walls are of concrete but without steel reinforcement (e.g., walls reinforced by wooden frames with concrete filling).

Wattle/adobe: This applies where the walls are some kind of wattle structure (e.g., pure wattle walls, wattle and thatch walls, and wattle daubed with earth plaster. Wattle is comprised of sticks inter-woven into a network.

Wood: This applies if the walls are made solely of wood.

Wood and concrete: This applies if both wood and concrete as described above are used.

Wood and brick: Score this for housing units where the materials used are both wood and brick (as described above).

Other: Include here all other types of wall construction material not described above.