This 1970’s purpose built block of flats recently developed cracking in the external skin of the traditional cavity constructed walls. The property owners, a social housing provider, called in Protectahome to establish the cause and to provide an appropriate repair solution. After a detailed survey of the entire building, the cracking was attributed to thermal movement due to the lack of any movement joints in the large panels of brickwork. Cracking at high level on the gable elevations was caused by an insufficient number of wall ties employed in the original construction.

A detailed specification for the installation of full height movement joints at six metre intervals was provided. Helifix DryFix ties were installed adjacent to the movement joints to tie together the two skins of cavity brickwork. A twin bladed diamond cutter was then used to form chases for the debond sleeves and 6mm Helibar set in Polyplus resin. Crack repairs were completed using 6mm Helibar and Helibond Grout. Additional DryFix wall ties were installed at high level in the gable walls. The work, completed by our own technicians, benefits from the provision of a Protectahome Long term Guarantee.