There's no universally best exterior paint. There's a right one for your wall, and working out which it is takes about five minutes at the property and saves a great deal of money later.
The three things a Costa Blanca exterior has to survive
Ultraviolet. Six months of very high UV breaks down the resin binder that holds a paint film together. As it degrades, pigment is released as fine powder — which is what "chalking" is, and why a wall leaves white dust on your hand.
Salt. Carried inland on the wind further than most people assume. It's hygroscopic, meaning it pulls moisture out of the air and holds it against the surface.
Thermal movement. A south-facing wall can swing dramatically in surface temperature between mid-afternoon and dawn, every day, all summer. The wall expands and contracts, and the coating on it has to move too or crack.
The main coating types
Standard acrylic masonry paint. Water-based, widely available, inexpensive. Fine on a sheltered, sound, modern render. It's the default in Spanish merchants and it's perfectly adequate in the right place — which is not a south-facing seafront elevation.
Elastomeric (flexible) coatings. Built to stretch, so they bridge fine cracks rather than splitting along them. Genuinely useful on render that's already crazing. The trade-off is that the thick, rubbery film is less breathable, so it's a poor choice on a wall with any moisture problem — it can trap water and blister.
Siloxane / silicone-resin masonry paint. The best all-round answer for most Spanish villas, and worth the extra cost. It's highly water-repellent on the surface while remaining vapour- permeable — so rain runs off but moisture inside the wall can still escape. It also holds colour well under UV and stays cleaner, because dirt doesn't bond to it as readily.
Mineral / silicate paints. Chemically bond into mineral substrates and are extremely breathable. The correct choice on traditional lime render, which is found on older village property inland. Limited colour range and less tolerant of what's already on the wall.
Breathability — the part that catches people out
Older Spanish construction, and anything built with lime render, is designed to breathe. Moisture moves through the masonry and evaporates from the surface. That's how the wall stays dry.
Seal that surface with a modern impermeable coating and the moisture has nowhere to go. It gathers behind the film, and eventually pushes it off — often taking render with it, and often a year or two later.
If your property is older, or the existing coating looks like a traditional lime wash, this matters more than anything else on this page.
What makes a repaint fail early
- Painting onto a chalking surface. The new coat bonds to loose powder, not to the wall. Chalky render needs a stabilising primer first, without exception.
- Not repairing the render. Painting over an open crack just paints the crack.
- Skipping the wash-down. Dust, salt and algae under a fresh coat guarantee poor adhesion.
- Very dark colours on hot elevations. They absorb far more heat, move more, and fade faster.
- Painting in the wrong conditions. Too hot and the film dries before it can form properly; too windy and airborne dust settles into it.
What we do
Every exterior job starts with establishing what's on the wall, whether it's still bonded, whether it's chalking and whether it needs to breathe. Only then does anything get specified.