Deck Railing Height Requirements
All decks greater than 30" above grade must have a guardrail. If you choose to install a guardrail on a deck lower than 30", you must still meet code requirements. Decks attached to single-family detached homes are regulated under the rules of the International Residential Code (IRC). The IRC requires guardrails to be at least 36" in height measured from the deck surface to the top of the rail. Commercial decks attached to multifamily buildings, such as apartment buildings or businesses, are regulated under the Internation Building Code (IBC). The IBC requires 42" high guardrails. In either case, you are allowed to build taller guardrails as long as they conform to all other requirements stated in the code. Most building departments in Canada require 42" high guardrails.
Measure from the deck floor to the top of the rail between posts. This must be at least 36" high to meet IRC requirements. Make sure your sweep space and all infill openings will not allow a 4" sphere to pass through.
Sweep Space Bottom Deck Rails

This popular rail style leaves a 4” space below the bottom rail to allow for snow and debris to be swept off the deck surface. Rail posts are attached to the deck frame and support the infill sections. Rail posts need to be properly fastened and should not be spaced more than about 6 feet apart to prevent a saggy or bouncy rail.
Many builders run a 2x6 top cap continuously over the top of the posts and top rail to provide a clean finished edge and the practical purpose of providing a surface to set glasses, etc. The pickets can be considerably shorter because they don’t need to be individually attached to the deck rim and they are raised off the floor. Most deck builders prefer this rail type for is simplicity and functionality above all others for wood rail construction.
Glass Rails
Installing glass rails will usually require you to build the rail frame first and take precise measurements to custom order the tempered safety glass...
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Railing planters are an easy way to add some color to your deck without taking up space. Follow these simple steps and get started on your railing planters today.
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Skirting can be an attractive feature that can be added to any low-level deck.
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Outdoor rugs are a great way to add additional style and protection to your deck or patio. Check out our recommendations for the best outdoor rugs.
Best Outdoor Kitchen Design Ideas For 2023
Make your backyard kitchen the place to be this year. Find unique outdoor kitchen ideas for summer BBQs, grilling, and outdoor parties at decks.com.
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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
Deck Railing Height Requirements
All decks greater than 30" above grade must have a guardrail. If you choose to install a guardrail on a deck lower than 30", you must still meet code requirements. Decks attached to single-family detached homes are regulated under the rules of the International Residential Code (IRC). The IRC requires guardrails to be at least 36" in height measured from the deck surface to the top of the rail. Commercial decks attached to multifamily buildings, such as apartment buildings or businesses, are regulated under the Internation Building Code (IBC). The IBC requires 42" high guardrails. In either case, you are allowed to build taller guardrails as long as they conform to all other requirements stated in the code. Most building departments in Canada require 42" high guardrails.
Measure from the deck floor to the top of the rail between posts. This must be at least 36" high to meet IRC requirements. Make sure your sweep space and all infill openings will not allow a 4" sphere to pass through.
Sweep Space Bottom Deck Rails

This popular rail style leaves a 4” space below the bottom rail to allow for snow and debris to be swept off the deck surface. Rail posts are attached to the deck frame and support the infill sections. Rail posts need to be properly fastened and should not be spaced more than about 6 feet apart to prevent a saggy or bouncy rail.
Many builders run a 2x6 top cap continuously over the top of the posts and top rail to provide a clean finished edge and the practical purpose of providing a surface to set glasses, etc. The pickets can be considerably shorter because they don’t need to be individually attached to the deck rim and they are raised off the floor. Most deck builders prefer this rail type for is simplicity and functionality above all others for wood rail construction.
Glass Rails
Installing glass rails will usually require you to build the rail frame first and take precise measurements to custom order the tempered safety glass...
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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