Follow these steps to build the perfect deck for your cabin.
The difference between a deck that will serve you well for a decade and one that will last at least twice that long could be only a few hundred dollars in better materials and supplies. Trust me. I’ve been there. I can tell you from experience that sitting in the boat fishing is a much more pleasant way to spend a summer evening than fixing a deck.
Since rebuilding a tired old deck is the last thing you’ll want to do during precious time at the cabin, start planning your new deck with the most durable materials and construction techniques in mind.
Follow these tips to get the optimum life out of your new deck:
1. Choose Long-lasting Decking
Everybody loves the look and aesthetics of a wood deck. If it’s well cared for and you start with quality, knot-free boards, a wood deck will last a long, long time. That goes for decks made of modern types of treated pine as well as the most expensive redwood and Brazilian hardwood, ipe (pronounced EE-pay).
And composite decking – many made from a blend of wood and plastic fibers – is another choice for decks that promises to last generations. Composite decking maintains its shape, doesn’t warp, shrink or expand, and is dimensionally consistent from board to board. It has no knotholes, will not rot and requires little maintenance. The downside is the up-front expense. While it costs more than wood, you may save money and frustration by never having to replace it or treat it with preservatives. But whatever material you choose, the next step is to build it right.
2. Get the Right Fasteners
While you may use nails on the deck’s substructure – for joist hangers and inside corner supports, for instance – you shouldn’t have a hammer anywhere near the job site when you’re adding the top deck boards. Nails as deck fasteners will loosen, pop, look sloppy and promote warping. They don’t hold up well in weather, tend to leave rust stains and won’t come out easily when you need to replace a board. So use screws instead.
Because of environmental and health concerns, most treated wood decking now utilizes an arsenic-free preservative. The new ACQ and TK treatments are more corrosive to metal screws, so you must pair the treated wood with fasteners promoted as ACQ-approved. It’s not enough nowadays to buy one-size-fits-all galvanized screws designed for decks. Match your screws precisely to the decking.
The same rule goes for composite decking. The manufacturer will recommend a fastener by head size and shape, shank width and a material that best suits the decking. The recommendation is often for a ceramic-coated screw that is color matched to the deck and resists rusting.
You can use galvanized screws on a more expensive cedar, redwood or ipe deck, but that’s kind of like putting cheap hubcaps on a Jaguar. If you can afford to double your budget for fasteners, go with stainless steel deck screws for the more expensive natural decking materials. They’ll hold better, last longer and look great throughout the life of your deck.
For an even better look using finer deck materials, choose a blind fastening system, which uses clips attached to the deck joists so you can secure the deck boards without drilling holes topside.
3. Beef Up the Base
While basic construction tenets recommend spacing deck joists 16 inches on center, there’s no rule that says you can’t bring that down to 12 inches on center to create a sturdier structure. In fact, deck-planning experts say you should reduce the joist spacing if you put the deck boards on a diagonal. Minimizing the spacing will increase rigidity and reduce flexing under loading. If you want to stick to the 16-inch on center spacing, you can add rigidity by doubling up on the center joist or those that make a greater span from end to end.
A second way to add bulk to the base is to overbuild the size of the structural supports. If you follow a deck plan that calls for 2x6-inch frame and joists, spend a little more to go with 2x8-inch lumber. If the design calls for 2x8-inch lumber, jump up to 2x10-inch stock. You may be surprised at the minimal added cost to over-build the standard deck design. A recent estimate for materials for the structure of a 12x20-foot treated wood deck was $450 using 2x8-inch lumber and $525 using 2x10-inch lumber. The added $75 is cheap insurance for a longer-lasting deck and will definitely give you a more solid, quality feel underfoot.
4. Supersize the Footings
In many parts of the country, deck life can be drastically reduced due to frost heaving. If you don’t build footings below the frost line for your area, you might as well count on throwing the deck out of level in a few, short seasons. When in the planning stage, call your local building inspector and ask about the frost line for your area. Deck flexing due to frost heave will loosen critical connections over the years and weaken the structure.
Inadequate footings in areas where soil stability is an issue can cause the same problems. If you have shifting sand or a rocky base to your deck, make sure you run footings deep enough to reduce the chances of shifting.
Some may be tempted to build a deck on concrete blocks placed on the ground or create other makeshift supports under a number of deck posts to hasten the process. But inadequate infrastructure means you’ll be tearing the deck down and replacing it sooner than you would have to otherwise. A proven, deeply dug concrete footing is your best bet for a structure that will last for a generation.
5. Make the Deck Breathe
A deck that breathes is a deck that lasts. Ample air circulation will protect your wood decking and under-structure from rot, warping and mildew.
Ensure at least a 1/8-inch gap between deck boards. A good way to achieve the proper spacing between boards is to place large nails (16d will do the trick) in the gap between the boards before fastening. Repeat using the same spacers as you finish installing the deck for uniform gaps.
Also make sure air can circulate under the deck. A deck frame that sits on the ground will wick up harmful moisture. Bring the bottom up a few inches off the ground at minimum. Decorative skirting around the outside of the deck inhibits air movement. If you want to create a barrier to critters taking up residence under the deck, use a wire mesh to skirt it.
6. Seal Early and Often
This applies to decks with natural wood decking boards, though durable ipe wood needs no preservatives. Exposed to the elements, an outdoor deck takes more of an environmental beating than any wood surface. Continual soakings, snow and ice, and the sun’s rays sap your deck of life. Frequent cleaning and sealing of the horizontal decking boards will help you wring the most years out of your deck.
Generally speaking, you’ll need to clean and seal your deck every two to three years, tending toward more frequent intervals in harsh northern climates. Allow your new wood deck to weather at least a few months before sealing for the first time to make sure boards are thoroughly dry.
When the deck begins to take on a faded or gray appearance, first clean it with a power washer on a light spray setting. You want to remove debris and provide a rough surface to take the sealer, but you don’t want to hit it hard enough to upbraid the wood grain. Allow the deck to dry for a day or two, then apply a light coat of sealer. If sealer is applied too heavily, it may flake off and require you to start the process over. And no one wants to do work twice – especially at the cabin.
Jim Kneiszel has learned the dos and don’ts of deck construction by building – and rebuilding – several of his own.