Decking Projects And Concrete: Everything You Wanted To Know

Without a doubt, the most important material consideration you need to make when planning a decking project is what kind of decking planks you'll use. Aside from that, however, you'll need to give a lot of thought, time and energy to concrete. Will you mix your own, or have it delivered? How will you pour the footers? Are you ready for this kind of responsibility?

OK, that last one is a trick question. Of course you are.

Concrete is the foundation of your decking project -- and therefore one of the most vital aspects of its construction. Poorly mixed or poured concrete can make for a bad decking experience overall, so it's important to make the right decisions here, and to pay careful attention when pouring your decks' footings.

Here are three things to pay attention to when planning your decking project.

Mixing it yourself.
Mixing concrete by hand is pretty easy -- it's simply a matter of adding water to dry mix, inside a wheelbarrow bed or masonry tub. A "high strength" label will likely give you the strongest piers and footings; if you're serious about your decking project, this isn't the place to skimp. Be sure to follow the instructions on the bag, and wear a mask and goggles -- concrete dust is a strong irritant.

Don't add too much water, or you'll weaken the mix. Aim for a consistency that holds its shape when you pick it up with a trowel.

Having it delivered.
Many contractors will deliver concrete by the yard (27 square feet), but some will deliver in smaller amounts as well. If you need more than about 20 cubic feet of concrete, it might be more cost-effective to hire a truck to deliver it to your home.

Pouring the Footings and Piers.
Since concrete sets so quickly, you'll need to pour quickly. Digging your footing holes ahead of time is common sense, but you might also want to think about preparing any concrete tube forms you'll be using. These sturdy cardboard tubes make excellent guides for pouring concrete, and they allow you to create piers that jut from the ground as much as you need. They're a decking contractor's best friend.

Depending on the decking project, you may use tube forms for the entire pier or only the top couple of feet. When measuring and cutting your tube forms, remember that there may be some settling.

Once you've filled the footer hole with concrete and tamped it down, you can set your tube form in the hole. Use a level to check that the form is level at the top. After this, you can fill the tube, using a rebar or other metal rod to mix out any air bubbles. Local building regulations may require you to use rebar to reinforce the concrete as well. After the tube is full, level the surface and tamp it down.

The Calculations.
If you're mixing concrete yourself, you'll need to do a bit of math to determine how much you'll need.

A 60-pound bag of dry-mix concrete will yield about half a cubic foot of concrete, and fill anywhere from nine to 20 inches of footing, depending on its width:

But there's a quick formula for determining how much concrete your footing will need: multiply the radius of the hole, squared, by the depth of the footer hole, and multiply it again by pi (3.14). The answer will be the number of cubic inches of concrete you'll need. To convert this to cubic feet, divide the number by 1,728. The final answer, multiplied by the number of footer holes you've dug, will give you the exact square footage you'll need to complete your deck.

Sequoia Supply, located in Warminster, PA, is the premier destination for decks and decking material. With a wide selection of wood and composite materials, decking accessories and other supplies, it's a one-stop shop for contractors and do-it-yourselfers alike.