How to prepare Radiata timber for staining?

Tiger202011

Hi there,

We’ll be building a low-level deck in the next couple of weeks using radiata pine timber. I wanted to check whether this would require tannin removal. I’ve found mixed information online — some sources say yes, others no. My understanding is that since radiata pine is a softwood with low tannin, it should only need a deck cleaner solution before applying stain which will be water based. 

Any advice would be greatly appreciated.

Thank you.

MitchellMc

Hi @Tiger202011,

When preparing radiata pine for staining, you do not need to remove tannins. Tannin removal is typically only necessary for tannin-rich timbers, such as Merbau, where the tannins can interfere with finishes. For radiata pine, a softwood with low tannin content, you can proceed to staining after giving the timber a thorough clean with a deck cleaner. But, even that isn't entirely necessary.

Water-based stains will penetrate the timber and allow any small amount of resin in knots to escape, so there is no risk of trapped resin causing issues. If you were painting instead of staining, it is advisable to let the timber weather for a few weeks first. This allows any trapped resins in the knots to naturally exude, preventing potential bubbling or staining under an impermeable paint coating. For a stained deck, simply cleaning the timber well is sufficient preparation before applying your water-based stain.

Please let me know if you have any questions.

Mitchell