Ask An Expert

Home » Expert Advice » Ask An Expert

Can I undercoat new spotted gum pallings or should we wait. What is the best undercoat? Oil or acrylic?

Woodsolutions Answer +

The major paint companies market products described as ‘3 in 1’ (primer-sealer-undercoat). We suggest one of these products, followed by two acrylic top coats. It doesn’t matter greatly whether the 3 in 1 prep coat is oil or acrylic, but acrylic top coats give best service on timber, so perhaps go with an acrylic prep coat for best compatibility. You will need to wait until the timber is dry before painting - this applies to unseasoned timber containing natural moisture and/or timber wet from rain. It is possible to paint damp wood but you risk blistering if the sun hits it later and draws moisture to the surface which is unable to escape through the paint film.

Paint, fence

My benchtop has osmo oil and around the sink and in areas of high use, the finish is coming away. We have reapplied the oil, we have sanded and reapplied the oil and lastly throughly cleaned (with osmo cleaner), sanded and reapplied. Although the oil appears to be absorbed, almost immediately, it returns to the previous state. Any ideas?

Woodsolutions Answer +

It’s not possible for us to have a detailed understanding of all the finishes on the market. We don’t carry out our own tests and we are not familiar with Osmo Polyx. If you are not satisfied with its performance perhaps it’s something to take up with the supplier. Osmo Polyx appears to be an oil-based finish. As a general rule we don’t recommend oils or waxes for areas where contact with water is likely. In our opinion the most satisfactory treatment for timber benchtops adjacent to sinks is polyurethane, applied to all surfaces including the edges of cutouts and the underside of the bench, ie. a complete envelope. Polyurethane forms a barrier against water and liquid spills, can be wiped clean easily, and is resistant to heat. However, if you intend to switch to polyurethane, note that any residual wax or oil may interfere with its curing, so all traces of the previous coating must be removed.


We have merbau outdoor wood garden furniture and decking. How often should this be stained or treated to maintain durability of 25 - 40 years?

Woodsolutions Answer +

Merbau is rated Durability Class 1 outdoors, out of contact with the ground, so it would have a probable life of 40+ years without any coating at all – unless you are in a particularly high rainfall area, or the decking is in the path of a watering system. Regular wetting will shorten the life of most timbers. If you leave it without a coating it will turn driftwood grey so you may wish to oil or stain it to keep a more natural colour. While not strictly necessary from a durability point of view, a finish will help to prevent weathering effects such as fine surface cracks or ‘checks’. Any of the products marketed as garden furniture oil or decking oil are suitable. How often you re-coat depends on the level of exposure. A simple test is to sprinkle some water on the timber. If it forms droplets the finish is still doing its job. If it soaks in it’s time to re-coat. However, the timber might start to look ‘hungry’ before you reach that stage.

Sign up or Login to continue reading the answer.

Displaying 0/0

Show me 10 /20 /30

Haven't found what you're looking for?

If you have not found the answer for your question in the Search results, please  send us an email for a prompt response.


Are you looking for a supplier?

Social Media Feeds