How to repair flaking and cracking weatherboards?

djclloyd

I'm in a 6 year old townhouse. Some of our weatherboards have minor paint cracking & flaking. What is the best way of repairing this? Do I need to sand back the entire areas or just the affected areas?

There are also some small cracks between the weatherboard & aluminium joinery, including a large piece of degradation. Do I just reseal the cracks or do I need to do anything else?

MitchellMc

Welcome to the Bunnings Workshop community @djclloyd. It's terrific to have you join us and many thanks for your question on exterior painting.

The cracking and flaking you’re seeing is usually caused by moisture getting in behind the paint film. Once the painted coating is breached, even in a tiny spot, water can enter the timber and the pressure from that moisture will eventually push the paint off. You’re on the right track with your approach. You only need to sand and scrape the affected areas and the immediate surroundings, going back until you reach solid, well‑bound paint that isn’t lifting or chalky. After that, prime the bare timber properly, then re‑coat with good exterior paint. Once the paint has dried, go back with a flexible exterior filler and seal any gaps where water could get in, no matter how small. For the small cracks between the weatherboards and the aluminium joinery, the same flexible exterior filler is suitable. You shouldn’t need to do anything more there, just make sure the gap is properly sealed to stop water from penetrating behind the boards.

Please let me know if you have any questions.

Mitchell