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.
Building a Deck Around a Tree
Learn how to build a deck around a tree to allow the tree to grow and not damage its root system while digging footings.
Engineered Deck Beam
Use treated engineered deck beams for long spans with fewer posts and footings. Engineered beams can be designed and specially ordered from your lumberyard.
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.
Tile decking
Installing tile over a standard deck frame in an exterior environment is a recipe for trouble.
Picture Frame Decking
Install a picture frame or perimeter board to finish the edge of your deck with style.
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Railings
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Ledger
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Care
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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.
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Learn how to build a deck to properly support a hot tub or spa. Hot tubs are very heavy. Never place a hot tub on a deck that wasn't designed for the additional load.
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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
Tile decking
Installing tile over a standard deck frame in an exterior environment is a recipe for trouble.
How to Demolish & Remove a Deck
At some point, it might become necessary to remove an old deck, due to age or condition. Learn more about what's involved in a deck demolition and removal project.
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