Civil Engineering Reference
In-Depth Information
Chapter 10.1
Tiling
The Building Research Station
received a large number of enquiries
in the 1930s about the failure, in
particular detachment, of wall tiling.
One characteristic of this type of
failure, common to both wall and
floor tiling, is that the tiles usually
came away very cleanly from the
mortar bed indicating that it could be
difficult to obtain adequate adhesion
between tiles and mortar. Things
have improved considerably since
then, although failure to observe the
recommendations in British
Standards still leads to problems.
The larger the tile, the more likely
it was to distort slightly in the firing
process; therefore the more difficult
to lay to an acceptable finish.
However, modern manufacturing
techniques have largely overcome
this problem, and tiles of
comparatively large sizes are now
available. Any very slight size
discrepancies can be accommodated
in the joint.
See BS 6431
(266)
†
for further
information.
Joints
Tiles need to be laid to accurate joint
widths, and spacer lugs are provided
on some tiles to facilitate control of
joint width. Joints are commonly
filled with a proprietary grout, some
of which can be on the soft side.
Epoxy and polyester resin cements
give good waterproof joints since
adhesion to the tiles is good.
Movement joints should be filled
with a non rigid non hardening
material, for example silicone.
Characteristic details
Basic structure
Ceramic tiles have been made for
many years from a mixture of clays
and other materials, for example
crushed flints, which are then ground
and pressed in a semi-dry state into
the shape and size required. After the
first firing, the colouring and glaze is
then added to the biscuit, to produce
the finished products.
Ceramic tiles used to be available
in an enormous variety of sizes and
colours and it is impractical to list
these here. Most manufacturers
produced a range of standard sizes
designed to fit awkward spaces, and
to form rounded external and re-
entrant corners, coves and upstands,
a few of which are shown in Figure
10.2. The portfolios of different
sizes, shapes and colours of tiles
have, however, been further extended
since the 1980s, and now include
many imports; replacements for old
patterns may be very difficult or
impossible now to locate.
Main performance
requirements and defects
Strength and stability
Ceramic tiles are by nature brittle.
Impact resistance is likely to be the
main problem where there is a risk of
the wall being bumped (eg by sharp
edged trolleys). Where bedding is
inadequately spread over the whole
surface of the tile/substrate joint, the
risk of damage is compounded.
Figure 10.2
Rounded edge and bead fittings for wall
tiling
† BS 6431 was being revised at the time of publication. It
is intended that an ISO standard and a BS EN standard will
be issued in due course.
