Civil Engineering Reference
In-Depth Information
Cavity wall in field stones
The cavity is filled with small
stones in mortar, clay, perlite,
loose expanded clay or kieselguhr.
On the outer leaf the stones lean
outwards so that water runs off.
On top of the wall there are large
stones or a lime mortar. Good
insulation and windproof as a
sheltering wall.
Solid wall in field stones
Can be rendered stable. Requires
a lot of insulation as house wall.
Best as foundation wall, or foun-
dation to plinths.
Solid wall in cut stone
Can be rendered, very stable.
Requires a lot of insulation as
house wall. Best as foundation
wall or foundation to plinths.
Figure 13.9: Dry-stone walling techniques.
Masonry
When building with stone particular care needs to be taken with the corners of a
wall. In many examples, a larger squared stone is placed on the corner, while the
rest of the wall consists of smaller worked quarry stones or rubble.
Dry-stone walling
This technique demands great accuracy and contact between the stones. The stones
have to be placed tightly against each other vertically and through the depth of the
wall. Small flat angular stones can be put into the joints to fix the stones against
each other. A quarter of the area should have bonders (or through stones) that go
through the whole thickness of the wall between the inner and outer leaf.
Dry-stone walling is particularly appropriate for foundation walls as they
have the function of stopping any capillary action from occurring - no water can
be forced upwards in such a construction. This form of wall is not particularly
windproof. One way of working is to have two parallel walls with earth or
another fill between them. Better wind-proofing is achieved, but it has to be well
drained to avoid expansion and splitting due to frost.
Walls bonded with mortar
Many different mortars can be used for masonry (see 'Mortars'). Generally, lime
mortar and cement-lime mortar are the most suitable. The important properties
are elasticity and low resistance to moisture penetration, because stone itself is so
