If you do only one thing to look after your log home, look after the exterior finish. The stain on your logs is the sunscreen and raincoat that protects the wood underneath. Keep it healthy and your logs can last for generations; let it fail and you invite UV greying, water soaking in, and eventually rot. The work is not hard, but it runs on a cycle, and knowing that cycle saves you money and trouble.
Why the finish matters most
Two forces age exterior wood: ultraviolet light from the sun and water. UV breaks down the surface fibres and bleaches out colour, while water that soaks in feeds mould, rot, and movement. A quality penetrating stain blocks UV with pigment and sheds water, and a clear topcoat adds a sacrificial layer of weather resistance. The finish wears out before the wood does, which is exactly the point.
The wash-and-refresh cycle
Think of finish care as a rhythm rather than a one-time job. Inspect every year, wash as needed, and apply a light refresh coat every three to seven years. The range is wide because exposure varies wildly across one house.
South- and west-facing walls take the brunt of the sun and may need a refresh every three to four years. Sheltered north walls and anything under a deep overhang can go much longer. Treat each elevation on its own schedule instead of doing the whole house only when the worst wall fails.
How to test whether it is time
- Water test: spray a wall with a hose. If water beads and runs off, the finish is working. If it soaks in and darkens the wood, it is time to refresh.
- Colour: noticeable fading or a chalky, dull look means the pigment is spent.
- Greying: a silver-grey cast is UV damage to bare wood and a sign you have waited a little too long.
Choosing the right products
Stick with products made for log and timber homes and keep the system consistent. A typical system has three parts:
- Borate pre-treatment on bare or new wood, which guards against insects and fungal decay before you seal it in.
- A penetrating stain that carries the pigment and soaks into the wood rather than forming a brittle film.
- A clear topcoat that adds water repellency and gloss and takes the weathering so the stain lasts longer.
Avoid mixing brands or switching from a penetrating stain to a film-forming paint, which can peel and trap moisture. When in doubt, match what your builder originally applied.
Re-coating a wall, step by step
- Clean: wash the wall with a log-home cleaner and a soft brush or gentle pressure, then let it dry fully for a few dry days.
- Repair: spot-treat any grey or worn patches, re-apply borate to bare spots, and check that checks and joints are sealed.
- Mask: cover windows, trim, roofing, and plants you do not want stained.
- Apply: work in the shade, out of direct sun and not in the heat of the day, brushing or spraying-and-back-brushing with the grain, log by log, keeping a wet edge.
- Recoat: add the topcoat or a second stain coat per the manufacturer’s recoat window, then remove masking and inspect once dry.
Key takeaways
- The exterior finish is your logs’ main defence against UV and water; protect it first.
- Inspect yearly and refresh every three to seven years, sun-exposed walls more often.
- Use the water-bead test, plus fading and greying, to decide when to re-coat.
- Keep a consistent system: borate, penetrating stain, and a clear topcoat from one product line.
- Clean and dry the wall first, work in the shade, and follow the recoat window for a lasting result.