Decomposed granite and "party in your bare feet" are not two phrases that go together. Despite some nice plants, lots of mulch, and two amazing giant sequoia trees, the primary space of our backyard has been a broad expanse of the aforementioned, unusable crushed-up rock since we moved in. My visceral hatred of this stuff knows no bounds; it’s like the geological equivalent of cockroaches. It sticks in your shoes, scratches the floors when you track it in the house, collects leaves and can’t be swept, and is a perfect substrate for tiny grasses and weeds that have to be painstakingly pulled by hand. It’s also not really amenable to furniture, since you can’t slide chairs on it, and it’s not level. In other words, it sucks, and it was rendering a good chunk of our yard functionally useless.
After three years, we finally decided to change this sad state of affairs and build a deck. Or rather, have a deck built by someone who actually knows what they’re doing with power tools (i.e., not me). Not only will we be able to dine al fresco, but we’ll never track those little Satan-spawned rocks into the house again.
Over the coming days, I’ll be documenting the construction project with photos and exciting color commentary. Come back often to check out the story!
In true information-design-geek fashion, I made a schematic of the yard to help with the design process (shown above, click to enlarge). The area containing the decomposed granite (DG) is a long “U” on the east side of our house. The center of the U holds a small landing with two stairs that lead down to the DG area. Ten square paving stones live in the DG right in front of the steps, and essentially can’t be removed because they are embedded in concrete. The area outside the DG is a mix of plants, shrubs and trees, with a carpet of fir bark mulch beneath. Redwood 2x4s are used as a barrier between the DG and the mulch around the yard.
Backyard: After (sans accoutrements)
Our deck is really for two things: to create an outdoor space where we can entertain and eat outside, and to offer an area where we can chill out in our bare feet in the sun (e.g., reading, playing with pooch). Given these goals, we had to figure out what we wanted to do…Cover all the DG with deck? Or maybe only part of it?
Our neighbors in the compound (who share similarly designed homes) built decks over some of their DG, then had the rest hauled away. Our yard is one of the largest, so covering all of the DG with deck would be pretty expensive. On top of that, we’d lose landscape space….Covering part of the DG was the right option, but the question was, which part?
After going back and forth a bit, we finally opted for a deck that would cover the bulk of the DG and all of the paving stones, then wrap around the landing (diagram above, click to enlarge). The landing will stay in the same spot (since we’re not moving our double doors), and we’ll raise the deck so that it’s flush with what’s currently the last step down to the DG. The wrap-around area on the south side of the deck will be flush with the house, and is just the right size for our BBQ. The small strip of mulch on the northwest side of the deck will be replaced with a planter bed where we can grow herbs and veggies. About 60 square feet of the DG won’t be covered by the deck, so we’ll haul that crap away or shovel it up and hide it under the deck.
Both of our neighbors with decks went with a gorgeous Brazilian hardwood called Ipe (pronounced ee-pay). It’s a nearly perfect decking material: very hard, weather resistant, highly resistant to rot and fungi, and with a fire rating that matches that of concrete and steel. We’ll use 3/4″ x 5 1/2″ boards of various lengths (roughly $4 a linear foot), and we’ll clad the stairs and exterior face of the deck to provide a nice finished look.
The last detail worth mentioning is a miter joint we decided to create. Rather than have all of the boards run the same way, we decided that the wrap-around would look better with boards running east-west, while the rest of the deck ran north-south. This meant we needed a miter joint to connect the boards on one side of the deck with the other. Easy to draw, harder to plan and optimize in terms of materials.
So there you have it…A pretty basic deck. But what will it take to build?
Efficiency was one of our significant goals for the project. We wanted to minimize the amount of Ipe we used, both for cost and environmental reasons. Boards come in fixed lengths (from 8 to 20 ft in variable increments, depending on where you buy it). Rather than try to do the math, I decided to plan visually, so I measured the deck dimensions, and then laid things out in Omnigraffle as shown in the diagram below (click to enlarge):
The miter joint is the only thing that complicates things a little. If we had done boards the same direction for the entire deck, then it would have been easy. The miter joint meant we needed to have a mix of board lengths to minimize waste, along with an underlying diagonal support beam. The end result was a mix of board lengths from 8 to 20 ft, with placement dependent on geometry of the deck. The distribution of boards across the deck as a function of length is shown below (click to enlarge):
The structural plan (i.e., footings, joists, support structure) was put together by our carpenter, based on his previous experience building decks for our neighbors (and others). We’ll have 15 footings and a support structure made of pressure-treated lumber, with joists spaced 16″ on-center, and other reinforcements wherever they’re needed.
One last design detail: ventilation. All of my research indicated that one way to minimize cupping is to provide adequate cross ventilation under the deck, since cupping is caused by a moisture differential between the top and bottom of deck boards. Air flow is particularly important for decks that are low to the ground (like ours). After discussing things with the carpenter, we’ve decided we’ll do a few things:
- Excavate 3-4″ trenches underneath all of the joists (i.e., so they don’t touch the ground)
- Dig channels between the paving stones
- Place small circular vents on the sides of the deck
- Drill a number of 1/2″ holes in faces of the joists
The deck is being built by Anderson Moraes Carpentry in El Cerrito. Anderson is not only a knowledgeable and experienced carpenter; he’s also a great and funny guy with a very gentle demeanor. He and his colleague Roberto will be running the show, and I’ll be pitching in wherever I can. Charlie the wonder dog will be honorary foreman, overseeing all aspects of the project with his keen and curious eyes. Finally, Elaine will bring her great design and construction sensibilities, adding her thoughts as the project unfolds.
And so after all of the planning, it came time to break ground. The first big construction project at our house kicked off with a bang on June 22. Spades hit the soil, hands picked up hammers, and minds turned to measurements. If all goes well, in three weeks, we’ll have a new deck, a nifty planter box, and a blessed lack of DG in our yard.
Stay tuned for the next installment, coming soon!
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