by A J Newman (01-Jan-1988)
Please note that this is a scanned copy of a paper originally published in 1988, so the text is not as clear as in documents created as pdf files.
The most satisfactory solution to rain penetration of a wall is to identify and correct the underlying defect. But in cases where dampness is widespread and correction is difficult it may be better to improve the water resistance of the outer leaf. Available methods are repointing, application of a masonry waterproofer, painting, rendering, cladding and tile hanging. For cavity walls filled with insulation, diagnosis and correction is usually more difficult than for empty cavities, so protection of the outer leaf may be necessary if rain penetration occurs.
The purpose of this report is to describe methods for tracing the causes of dampness and to discuss the relative merits of the various remedial options. Somewhat greater emphasis is given to waterproofing treatments, but this is only because the other possibilities are already quite well documented elsewhere. Most of the discussion is in the context of cavity construction although much of it is also relevant to solid walls.