1. Cavity Wall TiesCavity Wall Ties
There are a variety of wall ties on the market. Most are
made from steel, either galvanised or stainless.
Some ties are made from plastic (right). All ties
incorporate drips to prevent water crossing the cavity.
They are available in various lengths to suit different
cavity widths.

2. Spacing of Wall TiesSpacing of Wall Ties
• The spacing of the tiesThe spacing of the ties
should be 900mmshould be 900mm
horizontally and 450mmhorizontally and 450mm
vertically.vertically.
• Additional ties are requiredAdditional ties are required
within 225mm (Code ofwithin 225mm (Code of
Practice - B. Regs requiresPractice - B. Regs requires
150mm but will soon be150mm but will soon be
altered) of the jambs of anyaltered) of the jambs of any
openings.openings.
• They should be no more thanThey should be no more than
300mm apart vertically300mm apart vertically
which effectively meanswhich effectively means
every three courses ofevery three courses of
brickwork (1 course ofbrickwork (1 course of
blockwork). Extra ties mayblockwork). Extra ties may
be required to supportbe required to support
insulation boards. insulation boards.

3. Ties spacing’s for gablesTies spacing’s for gables

5. The ties should ideally slope slightly outwards to help preventThe ties should ideally slope slightly outwards to help prevent
water reaching the inner leaf. Where partial cavity fill is specifiedwater reaching the inner leaf. Where partial cavity fill is specified
a special tie incorporating a large plastic retaining washer should bea special tie incorporating a large plastic retaining washer should be
used.used.

6. The ties should ideally slope slightly outwards to help prevent waterThe ties should ideally slope slightly outwards to help prevent water
reaching the inner leaf.reaching the inner leaf.
Where partial cavity fill is specified a special tie incorporating a largeWhere partial cavity fill is specified a special tie incorporating a large
plastic retaining washer should be used.plastic retaining washer should be used.
It is preferable to leave a cavity of 50mm although 25mm may beIt is preferable to leave a cavity of 50mm although 25mm may be
acceptable in sheltered situations.acceptable in sheltered situations.

7. Remember: ties sloping inwards may encourage water penetration,
and mortar droppings may also be a problem. Good practice should
avoid both these potential defects but they are not uncommon. Poor
work can be expensive to resolve.

8. These photos show partial insulation. On the left the ties has
been positioned but not the retaining washer - this can be seen
on the right. When using partial insulation extra ties are
required to support the boards.

9. Method of keeping cavity cleanMethod of keeping cavity clean
Bad positioning of DPC into theBad positioning of DPC into the
cavity may result in a build up ofcavity may result in a build up of
mortar droppingsmortar droppings