Wall Ties / Stitching Bars

 

Over time, however, the process of corrosion of mild steel cavity wall ties causes expansion of the cavity wall ties because the metallic oxide occupies a greater volume than the pure metal. This expansion has the effect of forcing apart the bricks above and below the bed joints in which the ties are laid, producing a pattern of horizontal cracks coinciding with the tie positions approximately every six courses. The corrosion of the cavity wall ties or the lack of sufficient cavity wall ties used in the original construction means that many properties require either further remedial wall ties to be inserted or the original cavity wall ties replaced.

The remedy for cavity wall tie corrosion is a straight forward procedure, identify the positions of existing cavity wall ties; install remedial wall ties in positions staggered from the original cavity wall ties. Wall tie replacement should be carried out in a uniform spacing pattern: a diamond formation with remedial wall ties at 900mm centres in courses set 450mm apart. At door and window openings the spacing is reduced to 300mm vertically.

The original cavity wall ties need to be isolated to prevent further damage to the cavity wall. Isolation of the cavity wall ties can be achieved by fitting Clan Sleeves around the external end of the cavity wall tie or complete removal of the cavity wall tie.

We have a range of stainless steel remedial wall ties to suit most situations as well as other types of stainless steel restraints, stitching bars and anchors to deal with the problems caused when buildings deteriorate and are no longer structurally sound. We have several products within our range which are patented, are unique to ourselves and may be the perfect solution to a problem you have.

In addition to our large range of remedial wall ties and restraint products our technical staff are able to advise you on all aspects of wall tie replacement for any job large or small.  Whether you need a specialist installer in your area or help with a specification our technical advisors are here to help. Simply call us on 01179 381 596.