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.
![Octagon](/media/kklhztet/octagon.jpg?format=webp)
The 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.
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.
How to Use Steel Metal Deck Support Posts and Columns
Steel deck posts with base plates can be used as an alternative to wood posts for supporting your deck.
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.
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
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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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Multi-level decks are very popular. Learn how to build a deck that steps up or down using shared posts and footing connections.
How to Install and Fasten Deck Fascia
Installing deck fascia can be easy if you have the proper tools, fasteners, and practical information that you’ll find right here.
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
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Learn about how to install composite decking. Topics include expansion and contraction issues and hidden fastener systems.
Explore Articles by Topic
![Footings](/media/3vsas025/all-articles_footings-2x.png?format=webpg&quality=80)
Footings
Information related to installing frost footings for decks
![Framing](/media/5wrarsgy/all-articles_framing-2x.png?format=webpg&quality=80)
Framing
Learn structural framing methods
![Decking](/media/meljt4np/all-articles_decking-2x.png?format=webpg&quality=80)
Decking
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Features
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![Design](/media/3bvpzvtz/all-articles_design-2x.png?format=webpg&quality=80)
Design
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![Planning](/media/qdenqrqv/all-articles_planning-2x.png?format=webpg&quality=80)
Planning
Learn about permits and working with contractors
![Porches and Patios](/media/sg5bst1z/all-articles_porches-and-patios-2x.png?format=webpg&quality=80)
Porches & Patios
Build a covered deck to enjoy all seasons
![Ledger](/media/0htjl4uu/all-articles_ledger-2x.png?format=webpg&quality=80)
Ledger
Proper attachment techniques
![Care](/media/qdpnwkry/all-articles_care-2x.png?format=webpg&quality=80)
Care
Maintain your deck to maintain your investment
![Materials](/media/zqfflkeo/all-articles_materials-2x.png?format=webpg&quality=80)
Materials
An overview on water drainage, benches, planters and lights