I regularly get questions about staining pressure treated lumber so here are some answers to as many of those questions as I can think of now. Before you read on, understand that staining or painting pressure treated lumber is just like staining untreated lumber. The main thing is that the wood needs to be clean and dry.

Can I stain pressure treated lumber?
Yes. You can stain pressure treated lumber as long as the wood is dry.

Why do I have to wait before staining pressure treated lumber?
The pressure treating process involves using a water-based solution to carry the treatment chemicals into the fibers of the lumber while under pressure. The process leaves the wood wet. If you want wood that is already dry, purchase KDAT lumber (KDAT = Kiln Dried After Treatment). KDAT is usually #1 and, yes, it costs more.

What are the consequences of staining pressure treated wood before it’s dry?
The stain or paint will probably bubble a little AND locking moisture into the wood might create a great place for fungus or rot to take hold and destroy some boards.

How long should I wait (allow the wood to dry) before staining pressure treated lumber?
It depends (of course). In a sunny, hot, and windy climate where it never rains your pressure treated lumber will probably be dry in a few weeks. In a cold and muggy climate (Seattle, for instance) it will take months for your wood to dry.

Some professionals recommend building whatever you are building and waiting about six months before staining pressure treated lumber. Then, stain the lumber after a few weeks of warm sunny weather. This is long enough for the wood to stabilize and for the water from treatment to evaporate. Remember to sweep and/or dust before applying the stain or paint.

Read further to learn about drying lumber yourself…

What kind of stain should I use for pressure treated lumber?
There are many stains and paints on the market. My favorites are based on working with lumber yards and seeing results from Consumer Reports. So, I like Cabot and Wolman brands. Many people thing Thompsons is the best because their marketing is the best. Many professionals completely disagree with the idea that Thompsons is any good at all. I am not saying anything about it – I’m just sayin’. The choice between water-based and oil-based stains is up to you. Read the backs of the cans. Back to staining pressure treated wood…

How should I stain pressure treated lumber? Or, how should I apply the stain?
Read the can because it varies with some stains but most stains can be applied with a brush, sprayer, or sponge. You will probably find a sprayer to be the easiest method.

How can I speed up the lumber drying process and stain my lumber sooner?
The best way is to buy kiln dried lumber (KDAT) in the first place. If you don’t want to do that…

You can dry lumber yourself but you need to be concerned about warping.

Ideally, you should stack the lumber on “sticks”, in the same way wood is stacked for kiln drying, and then strap the bundle to keep in straight. To do this, place a few small (1×1 or 2×2) sticks between each layer of lumber (perpendicular to the lumber and spaced about 3 feet apart) allowing for air flow between the layers. Then wrap a few straps around the lumber and make them tight. This allows air to reach all sides of the lumber while applying pressure to the lumber and minimizing the chance of warping. Warping is caused by the movement of moisture in and out of wood. You need to stabilize/support the wood while it dries. To take it to another level, point a box fan (or two) at the side of the bundle to speed up the flow of air across the lumber. If you set this up in your garage or some dry covered area your lumber will probably be adequately dry in a few weeks.

Should I stain pressure treated lumber yearly?
The answer is simple and goes something like this. If you want your deck/gazebo/arbor/whatever to look better for longer you should stain it on a yearly, or regular, basis. Of course, putting a protective stain or other coating on wood will make it last longer and look better while it lasts.

Staining pressure treated lumber is not rocket science. In fact, there is nothing remotely complicated about it but it does take time and if you don’t do it properly, you’ll mess it all up. If I did not make this point obvious enough above then let me say it again here:

Treated wood must be dry before you stain or paint it.

Enjoy your project. Wear gloves. Wear goggles. Be careful with tools. Work in ventilated areas.

Ipe (aka Brazilian hardwood, ironwood, and others) has become exceptionally popular as deck lumber in recent years – so much so that I have seen ipe deck lumber prices as high as $10 per board foot during short term ipe shortages.

The advantages of ipe deck lumber are clear and include:

• Excellent fire-resistance rating (A1, the same as concrete)
• Naturally high decay and insect resistance (basically, it’s a non-issue)
• Beautiful dark wood
• Hardness rating is about 3 times red oak
• Easily lasts 25 years as decking

When exposed to sun over time, Ipe deck lumber develops a silver-gray tone but its original dark color can be renewed with a pressure washer.

Working with Ipe Deck Lumber

Because of its hardness, ipe decking requires a few extra drill bits, saw blades, and time. Pre-drill all holes and keep your saw blades sharp to avoid damaging the wood while cutting. Prepare to kill a few drill bits and blades.

There are a few deck clip options you can use if you buy ipe deck lumber with grooves cut on the edges.? This allows you to build your ipe deck without having visible screws on top.

Ipe does not easily accept stains or protective treatments but most people buy largely for the color and its natural resistance is so excellent it usually does not need protection anyway.

Ipe Deck Lumber is NOT for Hippies

Ipe wood comes mostly from forests ranging from Mexico to Northern Argentina and many of the trees logged for ipe lumber are probably taken illegally.? Fortunately, most of the ipe lumber now used comes from cultivated trees.? If you are concerned about the social and environmental issues around using imported wood, check that your ipe deck lumber is FSC certified.? Although, FSC certifications have been forged before, you can generally rest assured that FSC certified ipe deck lumber comes from legitimate forests, conscientious timber companies, and responsible lumber dealers. Of course, responsibility might cost more.