Paint failure is almost always a system problem rather than a product
problem. The wrong coating on the right wall, or the right coating over the wrong
preparation, fails at the same rate either way. This page sets out what goes where.
Preparation decides the interval
A correctly prepared exterior in the Western Cape gives five to eight years depending on
exposure. The same paint over an unprepared surface can start lifting inside a season. The
sequence that matters is: wash down, kill any mould or lichen with a fungicidal wash, open
and fill cracks, sand back failing edges, prime bare or porous areas, then topcoat.
Matching the system to the wall
- Coastal elevations — salt-laden air off the Atlantic or False Bay
attacks a standard coating. A coastal-grade acrylic, and often a third coat on the seaward
side, is the difference between three years and six. - Old lime plaster — common in Woodstock, the City Bowl, Stellenbosch and
Paarl. Lime has to breathe. Sealing it with a modern impermeable acrylic traps moisture in
the wall and the paint comes off in sheets, usually within a season. - Hot inland walls — thermal movement opens plaster cracks. A rigid
coating cracks again along the same line, so a flexible or crack-bridging system is the
right answer rather than a harder one. - Damp walls — no coating fixes damp. Rising damp, penetrating damp and
condensation look alike and need different remedies, and all three need diagnosing before
any paint is specified. - Roofs — a different substrate and a different product. Tile needs
sealing where it has gone porous; metal needs rust treatment first; both need moss and
lichen removed rather than coated over.
Coats and coverage
Two coats over a prepared surface is standard. Three is normal for a strong colour change
or an exposed exterior. Coverage runs at roughly 6 to 8 square metres per litre per coat on
smooth plaster, dropping to about 4 on bare plaster that has never been sealed. Between
coats, allow 4 to 6 hours in summer and longer in winter; a full cure takes about seven days
before the surface is properly hard.
Where this applies to your property
What a wall actually faces changes across the metro — salt and wind on the
Atlantic Seaboard, over a metre of rain a year
in the southern suburbs, and summers over 35
degrees in the Cape Winelands. Each of those pages
sets out the local version. For a price, send the quote form and we will specify the system
against your actual walls.