quambi house - Great Lakes Council

7Figure 13: Almost all the factors leadingto salt damage of brickwork are presentin this location: cement mortar, close andhigh paving, defective drainage, internalimpervious coating and splashing froman overflowing gutter. A redesign of allexternal drainage and paving at this site isstrongly recommended.Figure 14: Paving along the side of thebuilding is too high and would not complyto the Building Code of Australia orother requirements. The paving needsto be lowered and underfloor ventilationinstalled.3 RECOMMENDATIONS3.1 Salt removalAll three buildings have a damaging salt accumulation in the masonry walls, and all will benefit from removal of thesalt. Failure to remove the salt will lead to accelerating masonry damage. Again, details of the mechanisms and removalprocesses can be found in the technical guide.Of all the salt removal methods mentioned in the technical guide, the poultice method using “Cocoon” manufacturedby Westox Building Products appears to give the best results. Observations at all the buildings suggest that applicationwill only be required in the lower parts of the walls, up to about 1.5 m above ground level, except where imperviouscoatings have forced the salt further up the wall.3.2 Control of rising dampRising damp provides one of the vehicles for salt in masonry to be deposited near the surface and cause damage whenthe moisture evaporates. If this occurs low down in the building, then floors, wall plaster and internal timberwork willnot be damaged. If, in the other hand, the moisture evaporation level is forced higher up the wall then the vulnerableelements will be damaged.May 2010Masonry damageCouncil–owned buildings in Stroud