How to Prepare and Paint Exterior Wood
Proper preparation is the key to exterior wood paint lasting for years rather than months.
This guide explains how to prepare exterior wood correctly, when to paint, and how to apply wood paint so it adheres properly and protects timber long-term.
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Why preparation matters
Exterior wood is constantly exposed to moisture, sunlight and temperature changes. Proper preparation removes dirt, loose coatings and surface defects, allowing the paint to bond evenly and perform as intended over time.
Surface preparation for exterior wood for painting
Before painting, exterior wood should be clean, dry and sound. Taking time to prepare the surface helps prevent peeling, blistering and premature wear.
- Remove loose or flaking paint
- Clean the surface to remove dirt, algae or grease
- Allow the wood to dry fully
- Lightly sand rough or uneven areas
- Repair any cracks or damage
When is the best time to paint exterior wood?
Exterior wood should be painted in dry conditions when temperatures are mild and humidity is low. Avoid painting in direct rain, frost or very strong sunlight, as these conditions can affect how the paint dries and performs.
How to paint exterior wood
Exterior wood paint should be applied in even coats using a brush or roller suitable for the surface. Applying multiple thin coats rather than one thick coat helps achieve better coverage and durability.
- Stir paint thoroughly before use
- Apply along the grain of the wood
- Allow recommended drying time between coats
- Avoid overworking the paint
How to maintain painted exterior wood
Regular inspection and light maintenance can significantly extend the life of painted exterior wood. Cleaning surfaces occasionally and touching up worn areas early helps prevent more extensive repairs later.
Choosing the right exterior wood paint
Choosing a high-quality exterior wood paint helps ensure long-term protection and a consistent finish. Paints designed specifically for outdoor timber are formulated to be durable, flexible and breathable, supporting the natural movement of wood.
Frequently asked questions
Exterior wood must have a clean, dry sound surface for painting. This will need preparation and will depend on whether the timber is new, bare or previously painted.
Light sanding helps remove rough areas and improves paint adhesion, especially on weathered or previously painted timber.
Priming depends on the paint and timber condition. Bare or highly absorbent wood may benefit from a primer.
Two or more thin coats are usually recommended for best durability and coverage.
Painting should be avoided in cold, damp, or rainy conditions as this can affect drying and adhesion. Thorndown can be used in very low temperatures – but be careful it doesn’t freeze.
Wood should be completely dry before painting, particularly after cleaning or wet weather.
Dry weather is essential. It helps to be warm and a breeze is welcome. Extreme weather is best avoided.