How to Prepare Walls for Painting on a Big Bay Coastal Home

Preparation is critical for any paint job but is especially important on coastal properties where the conditions are more demanding and any weakness in preparation is quickly exposed. This guide covers the specific preparation requirements for exterior walls on Big Bay and West Coast homes.

Salt Removal: The Critical First Step

Before any other preparation on a coastal property, salt deposits must be removed from all exterior surfaces. A thorough high-pressure wash is the starting point — use clean water and work methodically from the top down. On properties very close to the ocean, a second rinse after the initial wash helps ensure all salt residue is removed. Salt left on the surface under new paint will attract moisture and cause blistering and adhesion failure.

Treating Algae and Biological Growth

Coastal humidity in Big Bay creates ideal conditions for algae, mould and lichen on exterior walls — particularly on shaded elevations. After washing, treat any biological growth with a proprietary fungicidal solution. Allow the solution to dwell on the surface for the manufacturer-recommended time before rinsing. Never paint over live biological growth — it will grow back through new paint within months and cause early failure.

Crack Repair and Priming

Thermal cycling and wind movement cause hairline cracking in plaster and render on West Coast homes. Fill all cracks with flexible acrylic exterior filler — rigidity is the enemy in a coastal environment that experiences temperature and wind movement. Apply an appropriate primer to all repaired and bare areas before the topcoat. On coastal properties, a penetrating primer that seals porous substrate is particularly valuable in preventing moisture ingress. See our guide to salt air and paint for product recommendations.

Big Bay Painters prepares every surface correctly before painting. We never cut corners on preparation — because in coastal conditions, it makes all the difference.