Refinishing Outdoor Wood

Lets Stain that Deck!

By Lawrence Winterburn

When you call paint contractors for a price to stain your deck often they won’t call back.  A wise painter knows what kind of jobs to stay away from. How-to instructions all give different advice, so who whould you trust? Just choosing the right stain is often the most daunting task. The EPA has banned a few chemicals in the last 3 years that has American stain companies scrambling for solutions. (no pun intended). They are looking for more appealing… options.

There are 4 types of stain formulations in solid or Semi-Transparent products. Solid stain looks like paint but shows some grain texture. Semi-transparent is more like a sealer with some colour that allows tonal differences in the grain to show through. Paint is thicker than stain and lays on the surface. Stain tends to penetrate into the grain. Why not use paint? Wood expands when it becomes wet and contracts when dry. Since what you are trying to coat changes shape constantly, paint tends to loosen and peel off in sheets.  Alkyd—Oil Based, you will need paint thinner to clean up your brushes, and don’t spill this stain on concrete—it is hard to remove. We get 5-7 years of durability on vertical structures using solid, and 2-3 years on horizontal surfaces using semi-transparent.

Use oil based product to stain materials prior to building your outdoor project—all 6 sides.  Expect less durability if you apply this product to an existing deck.  Oil based stain is known for being durable. Latex, has only been available for a decade and is appealing due to water clean up. Durability is still in question for most brands. The stain companies are telling us that this finish should be a match for oil in durability.  Use Latex stain if you are new to painting since it cleans up with water. If you are able to stain all 6 sides of the wood prior to installation this product will work better. If the wood is damp or has already been built you may find it last longer than oil.

Emulsions are combination of latex and oil stains. These products are often pricey and rumored to be the future for exterior coatings. Manufacturers are boasting more durability. I have had wildly varying results with these products so get names of people who have used it so that you can check durability before you buy. These products are often suitable for wet materials—check with the manufacturer.

Silicone sealers will penetrate slightly and are designed to be applied yearly. These are the products that you see water beading up on in commercials.   Silicone products will give best results when applied to dry wood. Keep in mind the finish will deteriorate quickly, but you can give it another coat anytime to make it look good again. Try this product when you are staining near a pool or spa. Pool chemicals are hard on most finishes.

For Cedar dry materials will accept stain better. It takes about 2 weeks for cedar lumber to dry and P.T. materials normally 3 weeks. If the pores of the wood are full of water the stain simply cannot get in.  If you have patience and a garage you could stack the material with thin strips of wood between layers, boards spaced an inch apart. Prop the garage door open slightly and place a fan so that air circulates between each board. If you’re worried about theft you can lock most doors with vice grips on the door track.  In a couple weeks you are ready to stain.

To dry a deck already in place—no sprinklers, water fights or rain for 2 or 3 weeks. In fact you are waiting for a drought. It happens rarely, however it is worth the wait.

Sand the wood with a random orbital sander loaded with 80 grit sand paper to open up the pores. This will enable the stain to penetrate more deeply and last longer. Always wear a mask to avoid being poisoned or becoming impotent. Red cedar contains natural preservatives that are toxic to insects and humans. Pressure treated lumber contains numerous chemicals known to cause cancer. Wear a respirator and do all sanding outdoors. It won’t really make you impotent, but wear a mask!

Use a roller or brush to apply stain. Brushing in both directions after laying on the stain will help force it into the pores and bring up the grain. A good quality brush that is suitable for the product will make the job easier with less mess. Why is it that a professional painter can load up a brush and rarely spill a drop? The reason—mainly technique, the other half of the story is the brush. Ask your stain retailer to recommend a good one. (Normally about $30.00)

For Pressure Treated projects, formulations have changed in the pressure treating process. Specially formulated stain designed for P.T. materials may not be compatible with this new P.T. formula.  It may take a while for products to develop that work well.  Try a silicone-based product or call the manufacturer to ask whether it is compatible with the new P.T. material.

But I already have stain on my deck!

When the stain is peeling—short of waiting for all the stain to flake off or chemically stripping you don’t have many options. Removing loose stain and giving the deck another coat of the same type of stain is best. Try to make sure the deck is dry, sand the bare spots and give it another go. Most products bind well to themselves, but not to other products.

Using 2 colours will save you work later! Use 2 colours—semi on the horizontals and solid colour for the verticals. When it comes time to re-stain you may only have to redo the decking and handrail caps.

Sunlight is the Enemy of Stain Application. Wet down a deck on a sunny day. Within minutes the surface of the deck is dry again. The heat created by wet stain heated by sunlight will actually separate the ingredients that make up the stain. You will have wasted time staining, and also the time it will take to remove it next year. Stain on an overcast day.

Have you have ever wondered why some company hasn’t created the perfect stain?  With so many ways the application can go wrong—doing a better job applying your finish may be more important than how much you spend on stain.

This is a brief version of our article: Exterior Stain

Lawrence Winterburn is the President of and has been involved in the woodwork/contracting/design business for 30 years. His work and writing has been showcased in numerous magazines newspaper and television venues in North America. DIY and Professional Woodwork Plans are available for purchase from this website. He also designs and installs outdoor woodwork features across Ontario through the “Builder Group” licensing program.