What does building a deck involve?

Building a deck in Virginia is a small construction project with a permit, a plan the county reviews, and inspections at set stages. Virginia's building code says a permit is needed before the construction of a building or structure, and for installations or alterations involving any structural component.^[1] A deck has footings, posts, beams, joists and usually a ledger bolted to the house, so every part of it is structural. Here is what the job involves, in the order it happens, so you know what you are paying for and what to ask a builder.

Design and the permit

The work starts on paper. A builder settles the size, height, shape, stairs and railing style, then sizes the framing for the loads. For scale, Fairfax County's typical deck details are designed for a 40 pound per square foot live load and a 10 pound per square foot dead load.^[4] Hot tubs, roofs and privacy walls add load, which is why they change the design.

Counties ask for two kinds of drawing. Loudoun County says a building permit and a zoning permit are required for all decks.^[2] York County asks for a plot plan showing the setbacks from the closest point of the deck to each property line, and construction plans that include the details of the deck's attachment to the house and the guard rail and picket framing.^[3] York also says a deck that will hold a hot tub needs a design sealed by a Registered Design Professional.^[3] For the permit itself, see do you need a permit to build a deck in Virginia.

Materials

Fairfax's details call for preservative-treated southern pine, grade #2 or better, for the frame. Under those details, lumber that touches the ground has to be rated for ground contact, and not all treated lumber is.^[4] Metal parts are specified too: joist hangers and post anchors have to be stainless steel or carry a G-185 galvanized coating.^[4] Composite or PVC boards are often used for the decking and railings over a wood frame; a good quote names the exact product.

Locating utilities and digging footings

Before anyone digs, the buried lines get marked. Virginia law says no one may begin any excavation without first submitting a locate request to the notification center,^[5] which is Miss Utility at 811, and Loudoun tells owners to call at least 48 hours before excavating.^[2]

Footings carry the deck's weight into the ground. Both Fairfax and Loudoun set footings at least 24 inches below grade, bearing on solid soil,^[4][2] and Fairfax's drawings mark 24 inches as the frost depth.^[4] Next to the house there is an extra rule: under the Fairfax details, a footing closer than 5 feet to the house wall has to bear at the same elevation as the house's own footings.^[4] The footing holes are inspected before concrete goes in.

Framing: posts, beams and joists

Posts stand on the footings and carry beams, and joists span from the beam to the house or to a second beam. Posts are 6x6 under the Fairfax details, with 4x4 allowed only for posts 2.5 feet tall or less.^[4] Joist size depends on the span and spacing, which is why county span tables exist. Connections are made with rated hangers, bolts and brackets rather than nails alone.

The ledger: where most failures start

An attached deck hangs one side on a ledger board fastened to the house's band board. This is the most demanding part of the build. Under the Fairfax details, the siding has to come off where the ledger goes, and continuous flashing is required where it meets wood framing.^[4] Attaching a ledger through brick veneer is prohibited,^[4] and if the band board's ability to carry the deck cannot be verified, a free-standing deck or an engineered design is required.^[4] Loudoun inspectors may ask for access inside the house to verify the ledger is solidly attached.^[2] If you are worried about an existing deck, see how to know if a deck ledger board is failing.

Decking, guards, stairs and lighting

With the frame inspected, the boards go on. Under the Fairfax details, each decking board must bear on at least three joists.^[4] Guards, handrails and stairs follow, with stair rise and run held to tight limits. Power is part of the job too: Fairfax's details require at least one electrical receptacle along the deck's perimeter and a light source for each stairway,^[4] and Loudoun says an electrical permit may be needed for stairway lighting, hot tubs or spas.^[2] Have that work done by a qualified electrician.

The inspections

Loudoun requires three inspections: the footing holes before concrete is placed, the joists, beams, connections and mechanical attachments before the decking goes down, and a final inspection.^[2] Loudoun also says the approved plans or typical deck detail must be on the job site or no inspection will be performed.^[2]

Loudoun lists the most common reasons a deck fails inspection: fasteners that are not corrosion resistant in pressure-treated lumber, a ledger not attached to approved material on the house wall, ledger bolts or flashing that do not comply, and stair risers that vary more than the code allows.^[2] They are good questions to ask a builder before you sign.

When to call a licensed pro

For a new deck, that is from the start. Virginia licenses contractors by the size of the job: a Class C licence covers a single contract over $1,000 but less than $30,000, Class B covers $30,000 up to $150,000, and Class A covers $150,000 and more.^[6] The licence class on the builder's record should cover your contract price. Virginia's Board for Contractors says the contractor should apply for and obtain the permits, and the contract should say so.^[7] Be careful with a builder who asks you to take out the permit yourself: the permit holder becomes the general contractor and assumes responsibility for the overall job.^[7]

Before you sign, check the builder's licence and read what a deck costs to build in Virginia so you can compare quotes on the same terms.

Find a deck builder on Loclis

Loclis lists licensed businesses from Virginia's DPOR register, with each one's licence number and class. Browse deck building, see more exterior answers, look up exterior contractors in Blacksburg, or describe your deck once and local builders quote it.