How Washington State Deck Railing Codes Work

An Overview of the Washington State Building Codes

Building codes are an important aspect of any construction project, ensuring that buildings and other structures are safe and accessible. They are updated and enforced at the local level, and are often part of the State Building Code Council (SBCC), an entity created by the State Legislature. The 2015 Washington State Building Code is a collection of codes for all types of structures, including commercial and multifamily buildings, single-family residences and townhouses.
Because the State adopts the International Building Code (IBC) with some state- or local-specific amendments, residents can usually find familiar requirements not only in Washington’s building code but in other states’ as well . Most code requirements apply to new constructions, but there are often exemptions for items like small outdoor buildings or fences.
The IBC is centered on public safety, and the requirements it outlines ensure that buildings are structurally safe, protect from the elements, and are energy- and water-efficient. The IBC addresses safety features such as exit accessibility, structural integrity, storm protection, and fire hazard mitigation.
Washington’s building code is enforced by local authorities. Seattle, for example, has adopted amendment codes to the IBC, which are available online. The Building Code and Design Commission reviews proposed amendments for new codes, and evaluates the impacts that a building code change might have on the environment, property values, infrastructure, and other aspects of the community.

Deck Railing Specifications

In accordance with the Washington State Building Code Standards (RCW 19-27.031) and the International Residential Code Guidelines (IRC R311.7), deck railings are required by law in all locations that deck floor levels have a vertical drop greater than 30 inches. RCW requirements state that "open sides of stairways, landings and porches, except for those which cannot be entered unassisted from ground level, shall be provided with railings and the open sides of stairways shall have handrails". There is also no distinction between new and pre-used buildings regarding these regulations.
RAILINGS
Height: Railings must be at least 36 inches above the floor surface of the deck.
Spindle width: A maximum of 4 inches between spindles is allowed.
Swinging gates may be installed if they are capable of being secured in the closed position when not in use and have a self-closing mechanism. The safety of small children shouldn’t be compromised by railings that have the potential for large gaps or climbing features.

Permits & Inspections

When it comes to deck building or upgrading in Washington State, the process typically begins with obtaining the proper permits. The permitting process will ensure that the project complies with the state’s building code. Here we’ll look at this process, and the purpose of the deck railing inspection.
The first step to building or replacing the deck on your home is obtaining the proper permits. The permit process is used to confirm that the project follows Washington’s building code. If you’re working with a general contractor, they will be able to help you obtain the proper permits from the Department of Building and Safety for the area, or find a licensed contractor who will.
The purpose of MA Building Code Inspection is to verify that the deck railing structure complies with the code requirements. Inspectors are looking for certain structural components, including rail post connection details, top and bottom rail connection details, baluster connection details, guardrail and intermediate railing height criteria, and other similar criteria.
Once the deck install and structural framing is completed, the inspector will conduct an in-process inspection to verify that the correct structural framing is being installed. Now that the state has its own building code (WABO), there are additional inspections to ensure public safety. The inspectors offer pre-inspection consultations, which can aid in clarifying the requirements of the code before the build starts.

Safety Concerns

Safety is a primary concern when it comes to deck railing. This is especially true when you consider that as the rails break down, they are far more likely to fail, presenting a major injury risk. The National Association of Certified Home Inspectors warns that "the most common collapse [is] the railing sliding out of the end of the joist it was attached to," but they also note that it’s common for lateral pressure to cause "fence style" railings to buckle out.
Washington state code requires that the top rail be at least 36 inches above the deck surface. The top rail must have a minimum 4-inch vertical height. You may not have an opening greater than 4 inches across. Both requirements are structured to prevent a child from rolling under or over the top rail. Most states and building codes take a similar approach to deck railings over 30 inches in height.
Beyond just the height requirements of Washington state deck railing code , there are numerous structural requirements to ensure that the railing is sturdy and applicable to what you want. For instance, the guard post connection must be capable of resisting a horizontal force of at least 200 pounds applied at any point along the top rail. All of the pickets must be fastened securely and no more than 4 inches apart to help prevent children from slipping through.
Interestingly, while pool alarms are actually required in many areas, an alarm system is not required on your deck railing. Standard warnings on the railing aren’t sufficient for the Washington state code, which does require a sign that reads: "Keep Children Off This Deck or Balcony. The Wall or Railing is Not a Barrier. Do Not Climb." This has to be affixed at a point the public can easily see where the public can do the most harm, such as on the front edge of an upper deck or balcony.

Common Errors in Deck Railing Construction

The most common mistake that homeowners make is to assume that because their deck is only one foot off the ground, it does not require a railing. The dimension of distance above grade is irrelevant to the code. If "any portion of an elevated walking surface" is more than 30 inches above grade, a guard is required. Put another way, if any part of your walking surface is higher than 30 inches, the same requirements apply as would if your deck were a foot in the air, or even ten feet. There are some exceptions to this rule, and some cities may allow a guard to be omitted on stairs, for example, but it is always better to assume the guard is required, and then move on from there.
Another mistake that homeowners make is not to pay attention to how the guard is installed. There are several proper manners to install guards, and several improper manners. First, what the code does not require is the guard to be mounted to the top of the deck joists. In fact, anytime you can avoid mounting a deck onto joists the better. Of course, mounting to the band above is one way to minimize problems with the joists themselves over time. In addition, the code provides: "Guards and handrails shall not project into stairways more than 41/2 inches." The key word here is "more," so there is no restriction at all on projection into a stairway unless you have a handrail and a guard both projecting into the stairs, in which case the combined projection into the stairs cannot exceed 41/2 inches. So if you have a guard only, and it projects into the stairway 12 inches, there is no violation.
And finally, a common mistake when hardiplank is used on a home. It is possible, and the codes suggest, that a guard can act as the attachment for the hardiplank. If the guard is fastened along the vertical section above the rim joist, however, the rim joist will rot out in short order, resulting in an expensive repair scenario. You will want again to attach directly to the band above, to avoid the same issue you would have with joists.

Resources for Homeowners and Builders

Owners and builders seeking additional resources for deck railing code requirements can visit the Washington State Building Code Council website for in-depth information on all statewide building codes, including decks and other structural elements. Alternatively, homeowners may consult local building department websites for more information on their local decks and rails code requirements . Both state and local websites include valuable resources, including pre-application checklists, the opportunity to sign up for email alerts, and lists of contacts at local departments. Finally, homeowners may find it prudent to consult a licensed contractor for a full assessment of deck railing code requirements.