Walls

Question 1

The commonest type of loadbearing wall

Answer 1

Brick

Question 2

Cavity walls are

Answer 2

Cavity walls are used mainly as external walls in
buildings particularly exposed to weather. The
object of the cavity is to prevent rain penetrating to
the inside face of the wall.

Question 3

Another type of construction, which uses brick as
the “outer skin”, is that of modern timber-framed
construction

Answer 3

Here the main structure is of timber
with the frame clad internally and externally with
building board usually of an insulating type

the outside of this, with a small gap, is laid a conventional
brick “skin”. A membrane of either plastic
or bitumenized paper is placed between the
inner and outer skins. In order to prevent firespread
in the cavity a system of fire stopping is
placed at appropriate spots in the cavity

Question 4

With a fire that has involved the cavity of a timber framed wall what may firefighters have to do

Answer 4

Even if construction is carried out to a good standard, firefighters may have to penetrate the inner skin to locate, and extinguish, a fire in the cavity.

Question 5

The stability of a brick or stone wall depends,

amongst other things on:

Answer 5

(a) Its thickness in relation to its height;
sufficient headers to tie the wall together);
and
(c) To some extent on its age;
(d) On any horizontal pressure or levering effect
which may be exerted on it.
I (b) On proper bonding (in particular on the use of

Question 6

A brick or stone wall, though capable of supporting

a considerable vertical load, can only

Answer 6

can only withstand
a comparatively small sideways or lateral pressure
and, for stability, the loading of a wall must be centred
within the middle third (Figure 5.33).
Provision is usually made in the design of the
structure to withstand any normal lateral pressure,
either by making the walls themselves thick
enough for the purpose, or by the erection of transverse
walls or buttresses.

Question 7

TF walls may allow fire spread due to

Answer 7

Poor workmanship in fire barriers
DIY
Age
Wear and tear

Question 8

TF walls/buildings under construction can

Answer 8

Rapid fire spread
Large amount exposed combustible sources
Large radiated heat ( protect nearby buildings )
Early structural collapse