You’ve already picked the stain color. You know exactly where the grill is going. But when it comes to the actual footprint of your new deck, most Portland homeowners hit a wall at one question: how big should a deck be? 10×12? 16×20? Something bigger?
Getting the size right the first time saves you from either an elbow-to-elbow gathering space or a chunk of decking you paid for and never use.
Learn how to think through different deck sizes, uses for each, and what different codes and setbacks might mean for your deck size before you begin your build.
Table of Contents
- How Big Should a Deck Be?
- 3 Uses To Consider When Deciding on Deck Size
- Standard Deck Sizes and What Each One Fits
- What Portland Codes and Setbacks Mean for Your Deck Size
- Frequently Asked Questions To Help Determine Ideal Deck Size
- Ready To Build the Right-Size Deck? Contact Three Rivers Custom Decks
How Big Should a Deck Be?
There’s no one-size-fits-all answer to how big a deck should be. The ideal size depends on:
- How you plan to use the space
- The size and layout of your yard
- Your budget
As a general rule, a deck should be large enough to comfortably accommodate your furniture and activities without overwhelming your home or yard. For example, a smaller deck may work well for a grill and a few chairs, while a larger entertaining space may need room for dining furniture, seating, and other outdoor features.
Because every property and lifestyle is different, working with an experienced deck builder can help you find the right balance of size, function, and design. For homeowners in the Portland area, a Portland deck contractor can help you design a custom deck tailored to your space, needs, and budget.
3 Uses To Consider When Deciding on Deck Size
The right deck size depends heavily on how you plan to use the space. A deck built mainly for morning coffee or relaxing with a book will have very different space requirements than one designed for family dinners, grilling, or larger gatherings. Before settling on dimensions, think about the activities and features you want your deck to accommodate and how much room each one will need.
#1: Dining and Entertaining
A dining area can take up more deck space than you might expect once you account for the table, seating, and enough room for guests to move around comfortably. When planning for dining and entertaining, consider:
- A round table seating four typically needs about 144 square feet once you account for chairs pulling back and someone walking behind a seated guest.
- Sit-down groups of 10–12 push that closer to 288 square feet.
- Chairs scooted back from the table can require another 2–3 feet.
#2: Lounging and Relaxing
Not every deck needs to host a crowd. If you’re hoping to use your deck space for relaxing, here’s what you should know:
- Lounging works fine on footprints as small as 8×10 to 10×12.
- A relaxing area might be best suited as a secondary deck off a bedroom.
- Smaller decks won’t leave room for a second function like dining once furniture’s in place.
#3: Grilling and Multi-Zone Living
This is where the square footage adds up fast:
- Budget roughly 15–20 square feet per person for standing or entertaining near the grill.
- A four-person hot tub alone can need 150–200 square feet of deck space once you add proper walkway clearance around it.
- Multi-zone decks hold up better with layered deck lighting ideas that visually define the grill station from the lounge area once the sun goes down.
Not sure your backyard can fit the deck you’re picturing? Request a free quote, and we’ll help you figure out what’s possible.
Standard Deck Sizes and What Each One Fits
Once you know your use case, these three size categories are a good starting benchmark for the Portland Metro area.
Small Deck (8×10 to 10×12)
These smaller footprints show up most on condos, townhomes, and narrow city lots. A smaller deck:
- Fits a bistro table or a couple of lounge chairs without trouble.
- Won’t comfortably fit a full dining set once chairs are added.
- Allows for low-maintenance materials if you keep expectations aligned with the square footage.
Medium Deck (12×16 to 14×20)
Many Portland-area homeowners find that a medium-sized deck offers enough room for everyday use without overwhelming the backyard. This range also falls within the national average deck size of roughly 200–400 square feet.
A medium deck can comfortably accommodate one primary use, such as a grill and a six-person dining table. If you want separate areas for dining, cooking, and lounging, however, the space can start to feel crowded quickly.
Large Deck (16×20 and Up)
A 16×20 deck or larger offers plenty of room for bigger gatherings, with enough space for 12 to 16 people to move around comfortably. At this size, you also have more flexibility to create distinct areas for dining, lounging, grilling, or a fire feature without making the deck feel crowded.
What Portland Codes and Setbacks Mean for Your Deck Size
Before finalizing your deck size, it’s important to consider local permitting requirements and any restrictions that apply to your property. Most attached decks in the Portland Metro area require residential deck permits, regardless of square footage.
Property line setbacks can also affect how much of your yard is available for a deck. Depending on your zoning and property, required setbacks may limit the dimensions or placement of the deck, particularly on smaller lots. If you belong to a Homeowners Association (HOA), additional rules may apply to the deck’s size, placement, materials, or design.
At Three Rivers Custom Decks, we account for these requirements as part of the planning process. That helps us recommend deck dimensions that work for your property and plans while meeting applicable permitting and zoning requirements.
Frequently Asked Questions To Help Determine Ideal Deck Size
Is a 12×12 Deck Too Small?
A 12×12 deck isn’t necessarily too small. At 144 square feet, it can comfortably accommodate four to six people for dining or a small seating area. However, space becomes limited if you want to combine multiple uses, such as dining, grilling, and lounging.
Before choosing a 12×12 deck, consider not only how many people will typically use it but also the furniture and features you want to include. If you entertain regularly or want room for more than one activity, a larger deck may be a better fit.
Is a 20×20 Deck Large?
Yes. At 400 square feet, a 20×20 deck is considered a large deck and provides enough space for several different uses. You can typically accommodate a dining area, lounge seating, and a grill while still leaving room for people to move comfortably.
For many Portland-area homes, a deck this size provides ample outdoor living space while still leaving plenty of usable yard. Whether 20×20 is appropriate for your property will ultimately depend on the size and layout of your home and lot, as well as how you plan to use the deck.
How Big Should a Deck Be for a Table?
When planning deck space for a table, account for the chairs and surrounding walking space as well as the table itself. A four-person round table may need roughly 144 square feet once you allow enough room to pull out chairs and move comfortably behind seated guests. A six- or eight-person rectangular table may require 200 square feet or more.
Measure your table and chairs together, then allow additional clearance between the dining area and railings, walls, or other deck features. This will give guests enough room to sit down, get up, and move around the table comfortably.
Ready To Build the Right-Size Deck? Contact Three Rivers Custom Decks
Guessing at deck size leads to one of two outcomes: a cramped space you outgrow in a year, or square footage you paid for and never use.
Our design team walks every Portland Metro homeowner through their use case, local code requirements, and furniture layout to help determine the perfect size deck for your home. We’ve built custom decks throughout the Greater Portland area for more than 25 years, and we’ll revise the design until you’re genuinely happy with it.
Request your free, no-obligation consultation today, and let’s figure out the right size for your backyard!