What is a Cavity Wall Tie?
A cavity wall tie is a reinforcement that is used in a cavity wall construction that ties the inner leaf to the external leaf of bricks/blocks or masonry. They are used to stabilise the wall construction and to stop the separate skins of the wall from moving away from each other.
The ends of the ties are designed to “lock” into the cement bed of the mortar joints in each skin. There is also a design element in the tie ( usually a twist or drip ) that stops the transfer of moisture from the outer leaf to the inner leaf of the wall construction.
Cavity walls usually now have insulation within the cavity that has been incorporated into the design of the wall construction or retrofitted with blown or foam insulation.
They usually take the form of galvanised fishtail types in the earlier years and later they then were constructed from galvanised twist wire and more recently stainless steel
Wall ties were introduced in the latter years of the 1900’s and become used widespread as virtually standard in the construction industry throughout the building boom of the 1920’s, 30’s and 40’s.
Walls that are of solid construction ( don’t have a cavity ) will not have cavity walls ties within their construction as a general rule although there are some exceptions where flat steel plates have been used in solid construction walls.