Ask The Builder: Nothing beats built-in deck bench seating

DEAR TIM: Last weekend I was at a party and sat on a bench that was built into the deck. It was such a clever idea, and it had handy armrests that were perfect to set food plates or drinks on. I want to build bench seating on my deck. What are the most important things to consider? Although I’m not a great do-it-yourselfer, I can follow directions. I want it to be strong and durable. – Aimee P., Carbondale, Ill.

DEAR AIMEE: I’m a big fan of deck bench seating. A few years ago my wife bought a free-standing teak bench that was seven feet long and about 24 inches wide. It came with a cushion. I loved laying down on that bench in the warm sun like a lizard on a rock.

Last year I completely remodeled two decks on my home and built a new deck that attached to the posts that support my upper deck. I knew when I was planning this new deck that I wanted to put in a new built-in bench, as the teak bench had seen better days.

I used the teak bench dimensions as a basis for my plan, but I ended up altering it to a degree to fit bench cushions we could find online that were a standard size. You don’t have to have cushions to sit on, but I recommend it. Find the cushions you like at an affordable price and then size the bench seat to fit the cushions. If you order custom-sized cushions made to fit a bench you make, the price might take your breath away.

Benches are just very wide chairs in my opinion. I don’t like hoping something is going to work so I always look at existing things and take measurements. I’m sure you have a favorite chair in your home that’s extremely comfortable. Measure how high off the floor the top of the seat is and how deep the seat is from front to back.

My guess is you’ll discover the seat is usually about 19 inches up off the floor. The front-to-back measurement will be about 22 inches. If you build a bench too high, your legs dangle. If it’s too low, you end up squatting uncomfortably. The front-to-back dimension is also critical so you don’t end up leaning back too far.

I built my bench with a 90-degree orientation to the seat and the back. The reason is the back of my bench does double duty as a wall that supports a long shelf my wife wanted me to make for potted plants.

If you’ve ever sat in an Adirondack chair, you may want to mimic this design for your bench. It’s more work to create the angled back and seat, but the long-term comfort of sitting on the bench may be worth it. The only disadvantage to this design is you can’t lay horizontally on the bench without getting jammed into the corner where the seat meets the back of the bench.

The other issue with the Adirondack style is the armrests on the typical chair help you get up out of the low chair. People sitting on a bench would not have these and it could be problematic for older folks to get up. Just keep that in mind as you plan.

I built the framework for my deck bench in less than an hour. If you looked at the different components after they were built, I just had four small rectangles that were various lengths and widths.

One of the rectangles formed the seat; I screwed the long edge into the tall vertical wall that forms the back of the bench. You might end up screwing your seat to your deck railing posts or to the wall of your home.

I built a low, long wall that was the same length as the seat. This wall was inset from the front of the bench about 5 inches. This wall provided plenty of support so the seat would never collapse. The inset is easier on your legs as some people tend to tuck their legs back a bit when sitting in a chair or on a bench.

At each end of the bench I had small walls that were the same height off the deck as the arms on several chairs I measured around my house. Once again, don’t guess. Find chairs that have arms on them and decide which height is the most comfortable, and make your end walls that high.

I capped my end walls with 1-by-6 material so it would serve as a great place to put smaller dessert plates and glasses or mugs. So far it’s been perfect.

I’d avoid using any nails when assembling all the components for this bench. You can buy wonderful coated timber screws that take the place of regular 16d nails. All the framing lumber should be treated to resist rot.

Be sure to purchase treated lumber that’s nice and straight. Store it inside in the shade if you can’t use it right away. You need all the pieces to be nice and straight as you go to assemble all the parts.