Q I work in Texas, and we’ve had to change the way we build decks around pools and spas. What’s up?
A Contributing editor and code official Glenn Mathewson responds: The International Code Council released a new model code this year, the 2012 International Swimming Pool and Spa Code. Many requirements related to pools and spas have long been in the codes, such as those regarding electrical bonding and nearby glazing. Never has code extended, however, to the properties and geometry of the walking surfaces surrounding pools and spas — until now. In the new code, section 306 specifically addresses deck surfaces adjacent to “aquatic vessels,” as the code refers to them; the section’s provisions aim at reducing the hazard of slipping and falling due to the wet environment around a pool or spa. In-ground, above-ground, portable, permanent — if a vessel holds more than 12 inches of water and is intended for recreation, it falls under this section.
The first provision in section 306 applies to the slip resistance of the decking material itself. All decking materials are required to be “slip resistant,” which is defined in chapter two of the code as a surface that has been so treated or constructed to significantly reduce the chance of a user slipping. The surface shall not be an abrasive hazard.
This provides about as much guidance as a speed limit sign stating that you “shall go slow enough to reduce the chance of an accident.” Who decides that, and how will you know you’re not exceeding the limits of the law? There is no standard that defines when something is or isn’t slip resistant, and the code provision doesn’t look for a test standard. I think the question to be answered is whether or not the decking is “treated or constructed to significantly reduce slipping.” There must be something obvious about the material’s surface that’s intended to prevent slipping. For unaltered wood decking, the answer, I guess, might be no; it’s just wood. For some man-made products, however, if the texture on the surface has been designed to “significantly reduce slipping,” that might satisfy some building officials.
Slope the Deck
Section 306.4 addresses the slope of a deck adjacent to a pool or spa. The idea is to pitch such decks so that water will drain off, thus reducing the slipping hazard. The code requires that water on the deck be no greater than 1/8 inch in depth 20 minutes after water ceases to be added. For reference, when water beads up on an oiled wood deck, it ponds to nearly 1/8 inch in depth. The code section goes on to require that wood and wood-plastic-composite decks be sloped at least 1/8 inch, but not more than 1/4 inch, in 12 inches.
Unfortunately, there is no language in this provision that defines the limits of its application. Does a spa in the corner of a large deck require the entire deck to slope, or just the area near the spa? What if a spa is placed on or adjacent to an existing deck? The provision offers no exceptions, so these questions will have to be answered by each individual inspector — much like having a speed limit sign that tells you to ask the officer with the radar gun for information.
Gap the Deck Boards
Section 306.5 requires gaps between the deck boards. While the intention is to provide drainage, the provision specifically requires “gaps,” thus various tongue-and-groove products might not be allowed. While many of those products do have drainage openings, they don’t have “gaps between deck boards,” so if you want to use them, you may have to convince the inspector that you’re meeting the intent and purpose of the provision through another means.
In case gapped, sloped, and slip-resistant deck boards still result in a fall, there is one more provision intended to provide for safety. Section 306.7 requires the following: The edges of all decks shall be radiused, tapered, or otherwise designed to eliminate sharp corners. If a fall occurs — despite the previously described provisions — any corners or edges of material will be a little kinder to our heads or bodies upon impact.
This code is brand-new and so far has been adopted as a local ordinance in only a handful of locations, including the state of Texas. The 2012 edition of this code will be revised next year in preparation for the 2015 edition. If you’d like to propose any changes to it, do so before the ICC’s deadline of January 3, 2013.
Contributing editor Glenn Mathewson is a building official in Westminster, Colo.