Decks and porches built in the front, side or back of homes often serve as an extension of indoor living space, providing a flat, comfortable place to spend time with family and friends. Decks are usually built right up against the side of a home so that they can easily be used for socializing, relaxing, dining and more. Decks make excellent outdoor party spaces. Depending on what they’re made of and how they’re built, decks do require maintenance and repair every so often.

As with most other residential repairs, the cost to repair a deck depends on the extent of the problem, the cost of materials needed and how long it takes a contractor or handyman to do the work. Some contractors charge by the square foot, and others create custom estimates after visiting the site to inspect the damage. Some deck repair project costs are based on how many workers are needed to finish the job in the amount of time agreed upon between the customer and the service provider. Most contractors charge 15–$25 per square foot for a deck made of pressure-treated wood. Installation of a 16x20-foot wooden deck costs $4,800–$8,000 on average.

Estimates

Joe Hernandez, owner of V&G Enterprises, in Hamden, Connecticut, always provides an estimate for the total project cost of any deck repair or construction job based on the deck size (how much needs to be repaired) and the type of repair needed. In his area, Hernandez sees wood rot fairly often because snow buildup during the winter, followed by spring melt-off, can cause damage to homeowners’ decks—especially if they were not built using pressure-treated wood or sound construction practices. Hernandez charges $40 per hour if he can manage a job by himself, but the hourly rate increases if he needs more workers to complete a job in the desired time frame or if it’s too much work to do alone. Hernandez warranties all decks he builds for five years and recommends staining decks rather than painting them. He procures all materials needed for a project without an "upcharge"—meaning, he does not charge customers more for materials than what he pays for them. He does, however, charge clients $50 to cover the lumber delivery fee.

Extent of repairs

Deck repairs can include patching or replacing areas where the deck material (usually wood) has rotted, twisted, warped, become loose or shrunk over time to create gaps between boards that are unsightly or hazardous. Contractors can repair most of these issue by replacing damaged boards with new material. Larger areas that need to be replaced will cost more than small areas.

Deck materials

Larry Skolkin of LMS Handy Services, in Hobe Sound, Florida, charges $12–$14 per square foot to repair an existing deck or install a new one. This price includes materials costs for pressure-treated wood decking (Skolkin’s top choice for deck material), galvanized steel hardware and a coat of Thompson’s WaterSeal waterproofing stain.

Skolkin says it’s not uncommon to get calls from customers who need him to repair a deck that was improperly installed—with nails instead of screws, for example—or using wood that is not treated to stand up to the moist air of Florida. If a customer wants a different type of decking material, such as a composite, the job could cost more. For example, composite decking material costs about 30 percent more than pressure-treated yellow pine. Some contractors recommend using harder wood, such as cedar or redwood, which also costs more than pine.

Site elevation

When having a new deck installed, the ground may first need to be leveled or, in some cases, the deck will need to be elevated to meet the door threshold of the house. In both situations, contractors will need to pour concrete footings for the deck to rest on, and this job will add to the overall cost. Adding skirting to conceal the area between the deck and the ground will also cost more in materials and labor, depending on the materials and design of the skirting. A solid board skirting and short brick walls typically cost more than wood lattice, for example.

Stairs and railings

Damage to deck railings, stairs, landings or built-in features such as benches can cost more to repair than the decking because of the additional time required to match the existing design and materials. If deck stairs are loose, a contractor can usually fix the problem by securing the loose stair tread with screws. This job can add a few hundred dollars to the overall cost, depending on how many stairs need to be fixed. Some contractors charge more to repair railings than to fix deck boards because of the extra effort required to match the original railing design.

Mildew

If a wood deck has succumbed to mildew, some contractors can pressure wash it and restain it for $250–$450, depending on the total square footage and extent of mildew buildup.

Termite damage

If a wood deck has been damaged by termites or the presence of termites is suspected, a pest management service may be needed to assess the extent of the infestation and exterminate the termites.