1. The development of wall structures After the foundations have been completed the external walls are set out and construction commenced. There are many methods of construction which have developed over the last century. The following slides feature some of these.

2. Stone walls Traditional walls of dwellings and Industrial buildings were constructed from stone which were found locally. If you look carefully at the picture shown above you will see that the larger stones were built in courses with small stones inter spaced. The walls were usually very thick at about 400 to 700mm in width. Most had no damp proof course included. Lime mortar was used to bind these stones together. Some of these stone walls were built with lime or more recently with sand and cement. Stone wall with lime plaster. Stone wall

3. One brick walls One brick thick walls were commonly used to build rows of red brick terrace houses in close proximity to mills. These houses were constructed cheaply by mill owners from brick which were usually made locally. These bricks were often constructed in English Bond creating a solid wall. The solid wall allowed moisture to travel from the outside of the wall to the inside causing damp patches on the wall inside the house. Damp proof courses were included in some of the one brick walls. Header course Stretcher course Damp proof course A section through a one brick wall in English Bond.

4. Cavity walls in block construction The first development to prevent the spread of damp into the inside of buildings was the cavity wall. These walls were constructed from two skins of brick or block joined together by twisted galvanized steel wall ties. The twist was constructed into the wall ties so that any moisture which tried to move across the cavity would drop off. Wall ties spaced at 450mm vertically D.P.C.

5. Cavity walls in brick construction with insulation This wall is similar in construction to the first cavity wall, the only exception being the inclusion of insulation. Wall ties are now manufactured from stainless steel. When cavity walls are used as part of a cellular structure they provide buildings which are structurally sound. Some of their other advantages are the prevention of damp penetrating to the inside of the building, fairly good thermal insulation properties and a cost efficient method of construction. 60mm thick insulation Plaster

6. Walls of the future Current cavity wall construction will be have to be improved over the next few years if a reduction in heat loss is to be achieved. This reduction is necessary in order to reduce the energy demands of our nation which will ultimately reduce green house gasses. The futuristic wall structure shown here may be one possible way of achieving a reduction in heat loss. Plaster stud wall Insulation

7. Timber frame walls Timber framed walls differ from those constructed of traditional brick and block work because the structural frame members are fabricated from wood. They transmit their loads onto the foundation through a common sole or base plate. Timber frame structures must comply with the building regulations in every aspect including resistance to fire.

8. Curtain wall for Industrial and commercial structures The photograph shows curtain walling which is cladding a leisure centre. Mullion Transom Glass curtain walling Composite panels for curtain walling

9. Curtain wall structures Curtain wall structures are a composite of mullion, transoms and infill panels which may be glass or an opaque material. Curtain walling is often used with rectangular framed structures. There is often an inner skin of block work. Glass infill panels represented in green Opaque infill panels represented in blue