Building Codes for Decks

Whether your clients are looking to upgrade the value of their homes or want a spot to relish the outdoors with family and friends, decks are an excellent choice. They elevate the appearance of a house and make for great relaxation spots where people can entertain guests and enjoy beautiful views of their property. Building a deck requires more than wood and tools — you must comply with specific building codes to ensure safety and quality.

This guide outlines the resources you need to learn about deck building codes and how to ensure your client gets the deck of their dreams.

What Are Building Codes, and Why Do They Exist?

Building codes are regulations by standard developing organizations (SDOs) to guide the design, construction, alteration and maintenance of buildings and structures like decks. Building codes aim to guarantee the safety, health and quality of life of building users. Failure to comply with these codes can result in you building a deck susceptible to structural failures.

It’s in your best interest to comply with building codes for the following reasons:

• Safety and protection: Poorly constructed decks pose a safety concern that puts people at risk. The last thing you want to build is a deck that can collapse anytime, causing serious injuries and death. Instead, you want one that is sturdy and safe to enjoy, and deck code compliance ensures that.
• Property value preservation: Decks add value to a property. But for a deck to qualify as value-adding, it must go beyond aesthetic appeal. Building a deck to code is one way to assure future buyers that structures on a property are safe and durable.
• Legal compliance requirements: Noncompliance with building code regulations can lead to several legal consequences, including fines and penalties. The appropriate authorities may also order defaulters to take their decks down or modify them, which will incur additional costs.

What Building Codes Apply to Decks?

Your local jurisdiction determines what building codes apply when constructing decks. Typically, states adopt and amend model codes such as the International Residential Code (IRC) and the International Building Code (IBC). Cities, counties and municipalities may add or adjust these requirements.

How to Find Local Building Codes

To find your local building codes, visit your city or county government’s building department. You can also visit their website or contact them by phone or in person to request deck building regulations for your project. Certain online tools may collate state building codes, but it’s always good practice to verify these against the government source.

Permit Requirements — When and How to Apply

One crucial thing you want to do before designing, constructing or repairing a deck is to confirm whether your client needs a building or zoning permit. This step will protect them from the legal consequences of building a deck without permits, where it’s mandatory.

The following details are deciding factors guiding building permit requirements for decks:

• Deck height thresholds: States may require a building or zoning permit for deck thresholds above or below a specific measurement.
• Attachment to building: In most cases, if your proposed deck will be attached to a building, you’ll require a permit for construction. On the other hand, a freestanding deck may not need a permit.
• Size limitations: Your building codes may allow you to construct a deck without a permit if it is within a certain size limit.

Permit Application Process

If your deck meets any of the criteria for mandatory permits, you’ll have to go through the following application process on behalf of your client:

1. Create a detailed plan with relevant drawings, components and dimensions for the deck.
2. Gather required documentation, including site plans outlining the property’s layout and where you plan to build the deck.
3. Submit your application to your local building authority.
4. Pay the application fee.

While these are general guidelines, be sure to consult your state or municipality’s rules regarding requesting and applying for building permits.

Deck Safety Codes — What Are the Requirements?

Particular specifications are required for different elements when building decks. Before starting your exciting new project, you should research the relevant residential deck construction requirements based on the location of the jobsite.

Foundation and Structural Requirements 

The foundation of your deck can make or break its structure. Take note of the following specifications for building a stable deck foundation resistant to shifting or collapse:

• Footing specifications: The thickness of your deck footing will depend on details like soil bearing capacity.
• Deck load capacity: Several factors impact a deck’s load capacity, including size and layout. The load capacity for residential decks is measured in pounds per square foot (psf) and factors in both the dead load — the weight of the deck itself — and live load — temporary weight additions like people or furniture.
• Framing requirements: Proper framing, joint spacing and beam sizing are essential for structural integrity.

Safety and Railing Requirements

Depending on the size and height of the deck, railings may be mandatory. Even if they are not required by law, these safety features are vital to prevent injury. The following factors influence deck railing codes:

• Guardrail height
• Stair handrail requirements
• Baluster spacing codes
• Stair riser and tread specifications

Material and Design Code Requirements

Not every material meets the regulations for building decks. The building code will outline specific requirements for deck materials and design that may include hardware and fastener standards, pressure-treated lumber or composite decking. For enhanced protection, use weatherproof and UV-resistant materials to keep the deck looking its best.

 Deck Inspection Process and Timeline

There will be three inspections during and after your deck building process to ensure you follow the proper standards. The inspection stages are as follows:

• Footing inspection: Before pouring in the concrete, an inspector will review and verify details like location, depth, dimensions and soil conditions.
• Framing inspection: An inspector will verify structural details like ledger boards to confirm proper installation during construction.
• Final inspection: After you complete your deck, an inspector will conduct a final inspection to confirm it is fit for use.

What Inspectors Look For

You want to ace every stage of the inspection process, and one way to do that is to learn what inspectors look for. The three main categories inspectors pay attention to are:

• Structural support
• Railing safety
• Material quality

Your goal should be to pass the inspection the first time. To do so, be mindful of these common reasons for inspection failures:

• Material restrictions
• Insufficient footing depth
• Incorrect ledger board installation
• Inadequate snow or wind load requirements
• Improper spacing of components like posts, joists and beams
• Unsafe handrails and stairs
• Inadequate post connections

Get Your Deck Right Every Time

At Wolf Home Products, we want to support and equip you to deliver the best solutions for your clients. We provide training and certification for our Wolf PRO contractors to enable them to be their best. In addition to training, we offer our contractors extra support and incentives to help them succeed. Review our selection of premium decking and porch products, or learn more about becoming a Wolf Pro today.