How many ties do I need & what wall tie spacing is recommended?
Provided that your walls are of a typical masonry cavity wall make-up, with each leaf being at least 90mm in thickness, you will need to install the remedial tying system at the rate of 2.5 wall ties per m2. Wall tie spacing should be at 900mm centres vertically by 450mm centres horizontally, in a staggered ‘domino 5’ pattern. An additional vertical row of wall ties should be inserted at open reveals (gable apexes, windows, door openings, etc.) so that there is 1 wall tie per 300mm (height) of wall. In the unlikely event that either wall is less than 90mm thick, wall tie spacing should increase from 2.5 ties / sq. metre to 5 ties per m2 (450 x 450mm). For wall tie replacement in brick clad timber frame construction wall tie installation should be spaced at 4.4 wall ties / m2.
