Exterior wall

[edit] Introduction

An exterior wall typically forms part of a building envelope, separating the accommodation inside from that outside. Its functions include:

• Environmental control – mediating between indoor and outdoor conditions.
• Security.
• Privacy.
• Fire control.
• Aesthetics.

It may include openings allowing access and ventilation and glazing to allow light in and views out. In loadbearing construction such as masonry, the exterior wall may also provide support to the combined dead, imposed and wind loads of the roof and floor construction and convey them to the foundations.

In a framed structure, the external walls may be non-loadbearing and are therefore relieved of any upper floor and roof loadings. However, they are normally self-supporting and are designed to resist wind loads, prevent the spread of fire and accommodate thermal movements.

Joints accommodating thermal movements may be required if long, uninterrupted wall lengths are involved.

[edit] Materials

Exterior walls can be made from a wide variety of materials either singly or in combination with other materials. These can include:

• Masonry such as stone, brick and block.
• Concrete.
• Timber.
• Metal cladding.
• Glass, metal or timber panels.
• GRP/GRC cladding.
• Terracotta.

For more information see: Types of wall and Cladding.

[edit] Construction systems used to build exterior walls

Various construction systems can be used to build external walls, including:

• Loadbearing – using stone, bricks and blocks, or reinforced concrete. Timber is used for log cabin construction.
• Framed – the exterior wall can be located around the structure, inside (thereby exposing the structure) or as infill panels located within the depth of the frame itself. Irrespective of the plane it is in, the exterior wall in these situations is usually referred to as ‘cladding’. These types of exterior wall wrap around the building’s structure, are typically non-loadbearing and serve as an aesthetic and climatic component. Tied back to the structure, they can be made of facing bricks, concrete blocks, timber panels, glass, plastic and other lightweight materials. For more information see: Cladding.
• Rainscreen – a thin façade made of metal, terracotta or other panel type is attached to a lightweight frame which is itself bolted to the building structure. In appearance, it is not usually possible to tell that the result is a façade of relatively little thickness. There is usually a ventilation gap between the back of the facing panel and the face (or inner wall) of the building. Rainscreens provide an opportunity to retrofit insulation to existing buildings. For more information see: Rainscreen.

[edit] Related articles on Designing Buildings Wiki

• Barrier wall system.
• Building fabric.
• Cladding.
• Crosswall construction.
• Curtain wall.
• Façade.
• Infill panel walls.
• Load-bearing wall.
• Masonry.
• Partition wall.
• Party wall.
• Rainscreen.
• Rubble masonry.
• Stud.
• Trombe wall.
• Types of wall.