How To Build an Octagon Deck
The most important thing to be concerned with while building an octagon deck is to keep it level and square. We recommend to start by setting the prenotched posts at each corner positioned at a 22.5 degree angle. Between each of these posts, you will install double flush beams. Make sure each beam is the same length and equidistant to the opposite side.
SaveThe perimeter framing will be flexible for you to adjust before adding additional framing. Use temporary supports to stabilize the frame while working. Once the deck perimeter is square and level, install joists using angled joist hangers to strengthen the octagon frame. Avoid installing joists to the corner intersections to prevent interfering with the post beam notch connections. Adding decking and bracing will improve the strength and structural stability of the octagon.
If you are planning on installing a gazebo on top of the octagon, make sure your footings are sized to support the extra weight of the roof and that the gazebo is properly attached to the frame.
How to Decorate Deck Support Columns
Browse some examples of decorative deck support posts for tall decks.
How to Size a Deck Beam
Learn about how to choose the correct size beam for your deck. We discuss engineered beams and "sandwiched" style beams.
Reinforcing Deck Rim or Band Joists
Learn a technique to strengthen your guard rails by installing a double rim joist and adding structural blocking to reduce bounce.
Decking Patterns
Installing your decking at a 45-degree angle is a popular style for decks. This can be done to reduce decking seams or just for appearance.
6 Best Alternatives to Wooden Decking
While wood decking was previously considered the standard material for building a deck, that’s changed. Homeowners have been exploring and embracing different types of materials, and the availability of alternative decking materials has grown significantly.
Best Hidden Fasteners for Decking
Hidden fasteners create a clean deck surface and can be used with composite, wood and other materials. Learn about hidden deck fasteners at Decks.com.
More Helpful Resources
Explore Articles by Topic
Footings
Information related to installing frost footings for decks
Framing
Learn structural framing methods
Decking
Learn about wood and composite decking materials
Stairs
An in-depth look at the complex issue of how to build stairs
Railings
How to install guardrails and handrails to meet IRC code
Features
An overview on water drainage, benches, planters and lights
Design
The basics of deck design
Planning
Learn about permits and working with contractors
Porches & Patios
Build a covered deck to enjoy all seasons
Ledger
Proper attachment techniques
Care
Maintain your deck to maintain your investment
Materials
An overview on water drainage, benches, planters and lights
Why is Joist Protection so Important for Your Deck?
If you’ve ever seen a piece of wood left out in the weather for any period of time, you know what happens: decay. Whether through wet rot, insect damage, or mildew, the fibers begin to break down.
Reinforcing Deck Rim or Band Joists
Learn a technique to strengthen your guard rails by installing a double rim joist and adding structural blocking to reduce bounce.
Beam Span Chart
Learn how to size your deck beam using this easy-to-use span table. Just cross-reference the post spacing and joist length to determine the beam size.
Building an Outdoor Space with James DeSantis
Composite decking can not be placed directly on concrete. But a substructure can solve for this. Explore this deck project with James DeSantis
Best Hidden Fasteners for Decking
Hidden fasteners create a clean deck surface and can be used with composite, wood and other materials. Learn about hidden deck fasteners at Decks.com.
Picture Frame Decking
Install a picture frame or perimeter board to finish the edge of your deck with style.
Explore Articles by Topic
Footings
Information related to installing frost footings for decks
Framing
Learn structural framing methods
Decking
Learn about wood and composite decking materials
Stairs
An in-depth look at the complex issue of how to build stairs
Railings
How to install guardrails and handrails to meet IRC code
Features
An overview on water drainage, benches, planters and lights
Design
The basics of deck design
Planning
Learn about permits and working with contractors
Porches & Patios
Build a covered deck to enjoy all seasons
Ledger
Proper attachment techniques
Care
Maintain your deck to maintain your investment
Materials
An overview on water drainage, benches, planters and lights