How to Design a Deck
Not only does a new deck add to the value of your home, but they also provide the perfect space to enjoy the great outdoors with your family and friends. Before building a deck, you’ll want to carefully design it to include features that match your lifestyle and complement the look of your home. Use this guide to ensure you thoroughly plan both the design and execution of your new space. Before you plan out the logistics for building your deck, like its height and railing type, you should first consider these general questions.
The most important consideration in deck design is how you will use it. Do you entertain frequently, and if so, how large of a group will you need space for? What kind of seating will you need; would you or your guests be more comfortable on built-in benches or patio furniture? Do you want the space arranged to accommodate conversations between small groups, or in one large common area? Will you need adequate lighting to entertain at night?
Try to imagine all the ways you'd like to use your deck because most design elements will be based on your answers to these questions.
The size and orientation of your property and house might limit you to one or two deck locations. However, this still leaves you with plenty of design options. You may be able to add a door, build a walkway, or incorporate a privacy screen. Also, consider which view you would prefer out of your choices.
You may be able to avoid prevailing winds by locating your deck where the house will provide some protection. Likewise, careful placement can minimize traffic noise, eliminate unwanted views, and provide additional privacy. Privacy considerations could be especially important if you want to incorporate a hot tub or swimming pool on your deck.
The climate in your area is a major factor when deciding where to place your deck. A north-side deck will likely be the coolest location. Southern or western orientations may be too warm in the middle of the summer unless you include an overhead screen or build the deck around an existing shady tree.
Before you begin designing your deck, you should first check your local zoning ordinances. These ordinances will limit the overall size of your deck, height of any privacy screens, and the minimum distance from your deck to your lot lines. Neighborhood or subdivision covenants may restrict the appearance of the structure, and you'll have to get approval for your design.
Also, check with the local building department to find out whether you'll be required to have a building permit, including what kind of plans you will have to submit. Finally, be sure to check with your local utility companies to properly locate buried pipes and utility lines before building.
Deck materials must not only be resistant to decay and insect damage but also withstand the effects of water and sun. Standard construction lumber such as fir, pine, or spruce may be treated to protect it from rot, but it won't hold up under extreme weather conditions or the ultraviolet rays in sunlight.
Pressure-treated pine, redwood, or cedar offer better durability and are eco-friendly. Pressure-treated material is the least expensive, and it can be stained to nearly any color you want. Redwood and cedar offer an added advantage in that they are soft, fine-grained woods that will resist splintering. If you use redwood or cedar, remember that only the heartwood, the reddish-colored portion of redwood or the dark brownish-orange part of the cedar board, is decay-resistant. The lighter-colored sapwood will deteriorate just as quickly as pine or spruce.
Planning Your Deck
Shape and Decking Pattern
Once you’ve decided on how large you want your deck, you can measure the size you want your deck to be on your lawn. Drive 4-foot stakes at the approximate corners and then tie a string between them at about the height of the railings. If possible, size your deck in 2-foot or 4-foot increments. You'll have to buy standard lumber lengths anyway, so it’s smarter to have a larger deck, if you want one, instead of wasting material and money.
A deck can be any shape you want, and in fact, simple changes like an angled corner or a 45-degree decking pattern can dress up a house with a long, plain wall. You can also add visual interest by wrapping the deck around a corner, adding built-in benches, integrating a fence or screen on one side, or even adding an overhead screen.
Usually, the decking should come to within 2-inches of the bottom of the access door from the house, with steps leading from the deck to the ground. On sloped ground, you may want to build your deck in multiple levels to follow the slope. Typically, wherever the deck is more than 48-inches off the ground, codes require that the posts be braced to prevent swaying and racking. However, you should check with your area’s codes for specifics.
A spa or hot tub can be set on the deck if the structure is reinforced to carry the weight of the water, or it can be set directly on a concrete slab on the ground, with the deck built around it. Existing trees and rocks can also be integrated into the deck by framing your deck around them; to do this, either cap the ends of the decking or contour the decking to the shape of the obstacle. If you work around a tree, leave at least 3-inches on all sides to allow for growth. Around a stationary object, such as a boulder, you must leave about 1/4 inch so the decking can expand and contract with temperature and moisture changes.
Railings are the most prominent visual element in a deck, and you can get as creative as you want with the design. They may be fastened to posts that run all the way to the ground, along the sides of the rim joists, or attached to the decking itself. They may be made of or include wood, metal, or even rope as long as the material satisfies structural requirements.
Your railing design will be limited primarily by building code regulations that are designed to ensure safety. Typically, those codes state that support posts may be no more than 6-feet apart and that the railing may have no spaces larger than 4-by-4 inches. Also keep in mind that the ends of the railing posts should be covered or cut at an angle to shed water, to minimize cracking, and splitting.
Steps and Stairs
Step and stair construction is closely regulated by building codes, just as railings are. As a rule, steps and stairs should be at least 36-inches wide. The rise, or the vertical distance between steps, should be no more than 7 1/2 inches and the width of a tread at least 10 inches. The slope should not be too steep; a 7-inch riser with a 10 1/2 inch tread is a common combination. Building codes will also govern how the stair is supported and attached and whether you need a railing.
Additional Structural Components
There are a few other structural components you should consider when planning your deck. Vertical posts are set in concrete or on piers set on a concrete footing. They are typically spaced 4-8 feet apart. Horizontal beams are set on the posts parallel to the decking to carry the weight of the deck.
Joists are run between the beams, typically 16-inches or 24-inches apart. They distribute the weight of the deck and allow you to use decking boards that wouldn't be strong enough to span the distance between the beams. Decking is laid over the joists to form the "floor" of the deck.
Railings are usually 36-42-inches high, and they should be designed so that no spaces between balusters are greater than 4 inches.
Final Design Sketching
Once you have a rough idea of what you want, draw two sketches: one of your lot, showing the deck as part of your landscaping plan, and one of your design. Use graph paper, making each square equal a given dimension to get all the components roughly to scale. For example, each square may equal 1 foot on your lot plan or 3 inches on your design. Take the sketch to your local home center or lumberyard, and ask a salesperson to estimate and price the materials you will need before you begin building your own deck.