A deck is one of the best value outdoor projects in Maryland, and one of the most common questions we get is simple: how much does it cost to build a deck, and should it be composite or wood? This guide answers both with real regional data and what we see on projects in Frederick, Hagerstown and Montgomery County.
Key takeaways
- A wood deck addition averaged about $18,400 and a composite deck about $24,350 in the South Atlantic region in 2025.
- Composite costs more up front but needs far less maintenance over 20 or more years.
- The framing underneath is pressure treated lumber either way, so footings and framing quality matter for both.
- Most decks in Frederick County need a permit. Read our deck permit guide.
How much does a new deck cost?
The 2025 Cost vs. Value report prices a 16 by 20 foot deck with stairs and railings. Here is how the two main options compared:
| Deck addition (16 x 20 ft) | South Atlantic average | National average | Cost recouped (South Atlantic) |
|---|---|---|---|
| Pressure treated wood | $18,397 | $18,263 | 82.9% |
| Composite | $24,347 | $25,096 | 87.3% |
Larger decks, second story decks, multi level designs, built in benches, lighting and upgraded railings all add cost. Very small ground level platforms cost less.
Composite vs wood: side by side
| Pressure treated wood | Composite | |
|---|---|---|
| Up front cost | Lower | Roughly 30 to 40 percent higher |
| Typical lifespan | 15 to 20 years with care | 25 to 30+ years; many carry 25 year or longer warranties |
| Maintenance | Clean and seal or stain every 2 to 3 years | Wash once or twice a year |
| Splinters and rot | Possible as boards age | No splinters, will not rot |
| Heat in summer | Stays cooler | Darker colors get hot in full sun |
| Look | Natural wood, can be stained any color | Consistent color and grain, many styles |
The real cost over 20 years
Wood looks cheaper, but staining or sealing every few years, replacing cupped and cracked boards and the occasional rail repair add up. Many Maryland homeowners find that composite costs about the same over the life of the deck, without spending spring weekends with a pressure washer and a stain brush. If you plan to sell in the next few years, wood still makes sense and recoups well.
Not sure which is right for your yard? We will price both options side by side on the same design.
What else affects deck cost
- Height: second story decks need taller posts, beams, stairs and more railing.
- Footings: footings must reach below the local frost depth set by your county building code. Rocky or clay soil adds labor.
- Ledger attachment: a deck attached to the house needs proper flashing and lag or through bolt connections. This is where poorly built decks fail.
- Railings: wood, composite, vinyl, aluminum and cable rail vary widely in price.
- Stairs and landings: each run of stairs adds materials and labor.
- Demolition: removing an old deck adds tear out and dumpster costs.
Repair, resurface or replace?
If the framing is sound and properly attached, you can often resurface an old deck by replacing the boards and railings with composite at lower cost than a new deck. If posts are rotted, the ledger was never flashed or the footings are shallow, it is time to rebuild from the ground up. We inspect the framing on every resurfacing job before quoting.
Permits and inspections
In Frederick County, most attached decks and decks above a certain height need a building permit with footing, framing and final inspections. Permits protect you when you sell, because unpermitted decks often show up in home inspections. We handle the drawings and permit process for every deck we build.
Frequently asked questions
How much does it cost to build a deck in Maryland?
A 16 by 20 foot deck averaged about $18,400 in pressure treated wood and about $24,350 in composite in the South Atlantic region, according to the 2025 Cost vs. Value report. Size, height, railings and stairs change the price.
Is a composite deck worth the extra cost?
For most homeowners staying more than five to seven years, yes. Composite needs little maintenance and lasts longer, so the total cost over time is often similar to wood.
How long does it take to build a deck?
Most residential decks take one to two weeks of construction once permits are approved, depending on size and inspections.
Do I need a permit for a deck in Frederick County?
Most attached decks and raised decks require a building permit and inspections in Frederick County. Read our deck permit guide for details, or let us handle it.
Get a deck estimate
We design and build wood and composite decks across Frederick County and nearby Maryland. Request your free deck estimate or call (240) 875-4120. Planning a patio too? See our patio construction page.