Finishing Indoor Wood

Q: I’m about to install a lot of tongue and groove hardwood on some walls and a ceiling, and I’d like your recommendation on how to finish it. I’ve been told to use two coats of sealer on the surface, sanding lightly between coats, followed by a single coat on the back of each board before installation. Is this a good game plan?

A: Yes, this sounds like a fine plan, though the difference between a great finish and a mediocre one depends in part on the specific finishing product you choose. My favourite oil-based urethane is Canadian Tire's own brand, Armor Coat, in a satin finish. It dries hard and offers excellent protection, though it does impart a yellowish hue to the wood. If you want a completely non-yellow look, choose a waterbased urethane. ICI Quick Drying Varnish (available at Glidden paint outlets) is an excellent waterbased formulation, with the Flecto product a close second. I mention these two items specifically because every other brand of waterbased urethane I’ve tried dries too quickly, leaving hardened air bubbles and brush marks behind. I don't usually find that a back coat is necessary on interior wood, though many experts recommend it. Either way, use 240-grit paper on a 1/4-sheet finishing sander to smooth the wood between coats. Two coats or urethane are a minimum, with better protection offered by three.