Outdoor Wood Furniture Sealer
Outdoor Wood Furniture Sealer TIPS
- Water causes outdoor lumber to crack
- Clean outdoor wood with Stain Solver oxygen bleach
- WATCH videos below for tips
- Use a synthetic-resin pigmented sealer for best results
- CLICK HERE to Get Tim's FREE & FUNNY Newsletter!
DEAR TIM: My outdoor wood furniture has weathered to a mottled gray and there is mildew covering it. My wife has informed me that I must make it look like new.
If I do a good enough job, I've been told I can then refinish the kid's play set. What's the best way to get the wood looking like new?
How should I clean it? What's the best sealer to use?
If you were doing this job, what secret tips can you offer to get the best results in the shortest amount of time? Steve P., Mannassas, VA
DEAR STEVE: It's just as important to keep your better half happy as it is to clean and protect outdoor wood furniture.
I urge you to maintain a positive attitude through this entire project. I've been married since 1974 to the same wonderful woman and have discovered that keeping her happy completing projects is some of the glue that holds our marriage together.
Outdoor Wood All The Same
Cleaning and sealing any outdoor wood is not much different than doing the same thing for a wood deck. Outdoor wood tables, chairs, fencing, wood play sets, arbors, etc. all take the same abuse from Mother Nature.
No Care = Cracks & Rot
If you fail to maintain outdoor wood it will eventually rot and crack to pieces. Chemically treated lumber used to be marketed saying it would resist rot for decades. It turns out this is not true.
Some wood like redwood, cedar, teak and other hardwoods contain varying degrees of natural wood preservatives. But water that soaks into all these wood species will cause them to crack and rot over time.
The cracks start out as tiny checking cracks. Water entering the wood causes it to expand. As it dries, it contracts.
This movement creates the tiny cracks. If water gets into the cracks, it soaks deeper into the wood causing even greater expansion and contraction forces that cause the cracks to get deeper and wider.
Stop Water - Stop Cracks
You can see why it's important to treat all wood with a water repellent on a regular basis to prevent water from getting into the wood. Do this every other year or so and your outdoor furniture and play set will look fantastic instead of resembling a 50-year-old fishing pier.
Clean With Stain Solver
I prefer to clean outdoor wood with Stain Solver certified organic oxygen bleach.
Stain Solver is made in the USA with USA ingredients. The active ingredient, sodium percarbonate, is made with food-grade-quality ingredients.
You mix the pure powder with warm water, stir until its dissolved and then brush or spray it onto the outdoor wood. It will begin to bubble and foam as the oxygen ions attack mold, mildew, algae, sun-damage old sealers and dirt.
It's best to work in the shade and keep the wood wet with the solution for 15-30 minutes. After that lightly scrub, rinse with clear water and the wood will look like new.
Don't use oxygen bleach on redwood as it can darken this wood species. Use oxalic acid to clean redwood.
Pressure Washers DESTROY Wood
Do not use a pressure washer to clean outdoor wood. It absolutely will damage the wood. The high-pressure stream of water erodes the softer lighter colored bands of spring wood that are found between the darker bands of summer wood grain.
Sand Raised Grain
Allow the wood to dry well after it's clean. The washing process almost always raises the grain of the wood.
This means you'll have to sand it to get it back to that smooth furniture finish. Don't skip this important step.
A palm sander works great for this project. This is an affordable power tool that works similar to a vibrating hair trimmer a barber might use to cut your hair.
Use a medium aluminum oxide sandpaper. This paper self sharpens itself as it's being used.
Synthetic Resin Sealer
Once the wood is sanded, you should seal it with a pigmented synthetic resin water repellent. Don't use an oil-based product.
Most oil-based sealers are food for mildew and algae. The manufacturers place mildewcides and algecides in the products to slow down the growth, but water and sun break down these chemicals.
Outdoor Wood Sealer Test Results
I did an extended test on many outdoor wood sealers and water repellents. The results were shocking. CLICK HERE to get the results of the test showing which sealer performed the BEST.
Colored Pigment = Sun Screen
The pigmented, or colored sealers, will keep the furniture looking spectacular. The pigment acts as a sun screen blocking the sun's ultraviolet (UV) light from turning the wood gray. Clear sealers will gray rapidly.
IMPORTANT TIP: I urge you to work in the shade when applying the sealers. Some sealers require you to apply two coats within 15 minutes of each other to get maximum protection.
Shade = Best Results
Working in direct sunlight can shorten this time dramatically leading to ugly spotting and overlaps.
Working in the shade is easier on you, the wood and the sealer. If you can move the furniture inside your garage or other covered work area, do so.
I realize this is impossible for the play set, so choose to work on an overcast day if possible.
Staining and sealing outdoor furniture is quite different than sealing a deck. It requires a fine touch so your brush strokes are not seen and you don't create any overlap marks.
Wet Edge Is Everything
You have to maintain a wet edge with the sealer. This means you stain each individual piece of wood completely never stopping until you reach the end of that piece of wood or it intersects with another piece of wood.
Failure to do this can result in very unattractive overlaps where the color of the sealer seems darker at the overlap area. If you allow the sealer to dry and then coat over it with a second coat, you get double the color pigment in the overlap area.
Applying Wood Sealers Video
Watch this quick video to see how I applied different wood sealers to start my first independent test years ago. I did a second more detailed test a few years after making this video. I was working in the sun here, but it's okay because I knew I'd have different sealers on the same piece of wood.