It might sound like a few weeks’ worth of labor to build a deck for your house, but it’s actually much easier than it sounds. If everything is planned out appropriately, it is possible, and the first step in preparing is acquiring knowledge.
Statutes at the state and local levels control the majority of components of deck design in order to make sure that users of decks and the decks themselves are safe. If you have a solid understanding of these requirements, you will be able to expedite the permitting process, prevent unpleasant surprises during construction, and build a deck that is both secure and long-lasting.
Before you can file for a building permit, the majority of planning agencies require that they first allow your deck. Even though the zoning standards for building a deck may be different in different jurisdictions, in general, they are as follows:
- Decks that are attached to a home are required to have setback requirements that are equivalent to those of the home itself.
- Decks that are freestanding are required to comply with the setback requirements for accessory structures.
2. Deck Foundation
Foundations support decks by transferring loads to the ground. The system includes footings made from concrete, deck posts, anchors, and post caps.
The normal depth of a footing is 12 inches. In some locations, they extend deeper due to frost lines or steep grades. Before excavating, it is essential to have a structural engineer design the size and placement of these foundations and ensure that they do not interfere with existing utilities. The sizes of your deck’s footings correspond to the joist and beam spans, therefore larger decks require larger footings.
A deck’s framework resembles that of a floor. It consists primarily of deck boards, joists, rim joists, and beams.
Deck boards compose the patio’s usable surface. They are the most apparent and most exposed aspect of the structure to the elements. The boards are supported by joists that run perpendicular to them and carry the weight of persons and objects between them. The deck boards are supported by the deck joists. Longer spans and broader spacing necessitate deeper boards. Joists may rest atop beams or suspend from their sides. Their ends are either connected to the house, attached to rim joists for lateral support, or capped with guardrail connectors.
4. Connection to Home – Know Your Options
Decks can either be detached or attached to the residence. By opting for a freestanding deck, you will protect your home’s envelope from the additional weight. Adding footings and framework to a structure incurs additional expenses.
Should you choose to join the deck to your home, the deck and home structures will need to connect. To accomplish this, you must identify the home’s rim joist, remove the nearby external finish, and install a ledger board. To prevent water from contacting the rim joist, the ledger must be covered with corrosion-resistant flashing. Deck joists can then be attached to the ledger by means of joist hangers.
5. Guardrail Requirements
Decks having an elevation greater than 30 inches above the ground must be equipped with guardrails along their open sides and at the stairs. Guardrails often include guard posts, balusters, bottom, and top railings. The system should satisfy the following criteria:
- The top rail must extend at least 42 inches above the deck surface or 34 inches above the stair steps.
- The bottom rail should not extend more than four inches above the deck surface.
- The supporting guard posts should be at least 4 × 4 and not more than 6 feet apart.
- Guard posts that run parallel to the joists may be attached to the rim joist, while those that run perpendicular may be attached to the exterior joist.
- The normally 2 × 2 balusters should be spaced fewer than 4 inches apart.
- Guardrails must be able to sustain a single 200-pound focused load in any direction at any position along the top rail.
If you are uncertain as to whether your guardrail system meets the aforementioned specifications, you should consult an expert before making a purchase.
Stairs allow access from your home to your deck and from your deck to your yard. The components of a set of deck stairs are treads, risers, stringers, footings, connections, and handrails.
Treads are the horizontal elements upon which individuals ascend and descend steps. They must be at least 10 inches deep and 36 inches long, which corresponds to a minimum stair width of 3 feet.
The vertical parts positioned between each tread are known as risers. The maximum riser height is 7 3/4 inches, and it might vary by up to 3/8 of an inch if identical risers cannot be used. If you choose not to use risers between treads, the tread-to-tread distance must be less than 4 inches.
The stringers are the slanted planks that support the treads, risers, and handrail, as well as the weight of stair users. If your stairs run to the backyard, the stringers will carry loads to a concrete footing at the base of the stairs. Cut stringers have notches that correspond to the stair’s contour, but solid stringers do not. Solid stringers are more durable and span greater distances.
7. Hardware and Lumber – Corrosion and Moisture Prevention
The enemy of structures is moisture. It leads to wood decay and metal rusting. Decks are particularly susceptible to water damage due to their exposure to the weather.
All of your deck’s framework members must be pressure-treated to prevent moisture-related concerns. Chemical preservatives are infused into the pores of pressure-treated wood, rendering it resistant to fungi, germs, and insects. Typically, local building rules demand that structural elements within 12 to 18 inches of exposed soil be pressure-treated, but it is wise to check with your local building official.
8. Seismic Requirements
If you are building a deck attached to your home, it must be secured against lateral loads with at least two hold-downs or other certified tension devices. Decks that stand-alone require bracing to remain upright in the event of an earthquake.
All elevated decks must have diagonal knee bracing between the posts and beams or posts and joists. Alternatively, sway-resistant connectors could be utilized. Cross bracing between pillars may also be required for elevated decks.
A construction permit is required for all decks that are attached to a residence and those that are 30 inches or taller. If your deck fits among these categories, submit a permit application as you would for any other construction project.
Some governing authorities provide standard, pre-approved deck designs. These accelerate the permit application process. If you wish to differ from a conventional design, you will require the following documentation to support your application for a deck permit:
- Plot plan
- Foundation plan
- Framing plan
10. Getting a Permit for a Previously Unpermitted Deck
The process for legalizing unpermitted work may vary depending on the authority holding jurisdiction, but it normally consists of the steps outlined below.
Consult with an architect and structural engineer to evaluate if the deck conforms with local and international code requirements, such as setback requirements, structural stability, and arrangement. If everything checks out, you should be able to file for a permit as you would for a brand-new project and proceed with little difficulty.