This article applies equally well to drying timber prior to consolidating it with a hardening agent, glueing it or applying a surface finish (paint, varnish or similar). It’s an important topic because no glue will adhere to wet wood, no paint will stick properly and you won’t even get Smiths CPES into the timber cells to harden them if those same cells are full of water! It exists as an article because it’s a question we are regularly asked, so it’s worth writing the answer down. Drying wood out isn’t hard, and it has to be done.
Drying wood out needs bare timber surfaces
Strip the paint or any other surface coating that may be on the wood. Paints are designed to stop water migrating through them – so please remove them first if they are present. This should at the bare minimum be done around the saturated areas, but please be aware that water will migrate through timber, so a larger bare area may yield faster results.
Dry wood using moving air
Once you have exposed the surface of the timber, just moving air over it will allow the trapped water to evaporate off the large surface area of the bare timber. Please note that:
- The air does not have to be hot. Using hair dryers etc. is unnecessary and potentially very dangerous.
- Ambient air, even near 100% humidity, will still carry off moisture.
- Keep the air moving, as if it reaches 100% humidity (locally near the surface of the wood) – it won’t carry any more water.
Depending on the season, you may have free moving air. If not provide for a fan to keep the air moving over the timber.
Drying timber out involves stopping it getting wet
If the wood is outside, and the weather is against you then you will have to provide some protection from the rain. Polythene sheet, a temporary construction, you have many choices – but please stop more water falling on your drying timber.
Wait for the wood to fully dry
It’s cheap, as you don’t need heat, and once you have your cover and moving air over your bare timber – nothing else needs to be done.
Don’t rush it, depending on the section of the timber and how wet it is, you may have to wait a week or even a month for a large rotten section. Use a moisture meter if you have one, or if you are going to be consolidating the rotten timber with Smiths Clear Penetrating Epoxy Sealer once dry, consider drilling a hole to pour it into and check the drill dust is dry.
