Q: I have been contemplating redoing my ancient deck and decided to solicit your comments and advice.
I laid this deck down about 40 years ago over a concrete slab at my home in Sunnyvale, Calif. The deck is approximately 30 feet long by 10 feet deep, consisting of extremely straight and relatively knot-free redwood 2-by-4s. I laid “sleepers” about three feet apart to keep the deck off the concrete and provide air space and support.
The deck is the usual weathered redwood color, and I like the appearance. However, over the years the sleepers have deteriorated, giving a rather springy feel to the deck, as well as allowing the nail heads to protrude, creating a potential walking hazard. I would like to remedy the situation next spring when the weather is better.
In addition, because of my inexperience, I spaced the 2-by-4s approximately 1/8 inch apart, so that when the boards shrank over the next 40 or so years, they allowed an enormous amount of debris to filter down onto the concrete, providing me with a potential harvest of rich compost when I remove the deck.
I intend to remove the existing decking and replace the sleepers with pressure-treated lumber to prevent, or at least slow, deterioration.
I then want to reuse the old decking materials, but I will place them as close together as I can, since I feel that they have shrunk to the maximum and certainly will not swell appreciably in the future.
It should give me and my family a smoother, less bouncy surface to walk on, and will make it much easier to sweep and keep clean.
I would also like to consider turning all the planks over and, if they look better, use the underside for the top surface. I would appreciate your comments and suggestions.
A: What a trip down memory lane. We did the exact same thing to a second-story deck on Bill’s triplex in Alameda.
He had an old roof that leaked. We removed the deck, replaced the roof and installed new sleepers. Then we flipped the decking over to give the deck a new look.
Your plans to rebuild your 40-year-old wonder are right on. We think we’ve got a couple of suggestions to enhance your plan and give you an even better result.
After four decades of wear and tear, the rotten sleepers probably look like Swiss cheese. This accounts for their spongy feel. Replacement is the only option. Your plan to use pressure-treated material is right. But there are two types of pressure-treated lumber. One is used for installation aboveground, the other for installation in the ground.
Even though your deck is aboveground, we recommend you use material meant for contact with the soil. The new sleepers won’t get a lot of air flow and will be in close proximity to moist concrete for a large portion of the year. The extra protection of the upgraded material will help ensure that the sleepers outlast all of us.
We also recommend that you place the sleepers on 24-inch centers rather than 3-foot centers. We know that most deck plans call for floor joists spaced at 36 inches for nominal 2-inch-thick decking. But we’ve found over the years that 24-inch spacing produces a much more solid-feeling deck. And it’s only a few more sticks of lumber.
Now for the decking. Remove it carefully and pull all the old nails. Once you’ve cleaned the patio, harvested your compost and installed the new sleepers, install the old decking with the bottom side up.
Use deck screws, not nails. Coated deck screws won’t stain the wood and they won’t work loose, creating a hazard. We don’t recommend that you butt the decking together. Rather, we suggest you leave a small space, 1/16 inch or so, to allow for expansion and contraction.
When you installed the original material 40 years ago, it was probably relatively green wood containing a fair amount of moisture. When it was exposed to the sun and wind it shrank. The 1/8-inch gap grew to 1/4 inch or more.
Now that the wood has acclimated, the natural expansion and contraction has stabilized. A small gap is OK, but butting the boards together risks warping during the rainy season.
One final thing: Consider treating the decking before installation. Saturate all sides of the decking with a clear, water-repellent sealer. This will prolong the life of the decking but will not affect the weathered look of the wood.
Before screwing down the decking, build yourself a dipping tank so that all four sides of each board can be treated. Take six pieces of decking. Stack three each in two piles about a foot apart. Place sheet plastic (minimum 6 mm) over the stacks and elevate the ends so a trough is formed between the stacks.
Fill the trough with about three inches of wood preservative and dip the decking, one board at a time. Remove the boards and stack them with spacers between each board and allow them to air-dry for a couple of days. Once dry, you’re ready to install them and complete your project. We’re confident you’ll be happy with the results.