#How to do a ledger board code#

But our testing has shown even more compelling reasons to not permit 2x2 ledger strips outdoors.

#How to do a ledger board code#

In a nutshell, a code requirement for a product that is not (apparently) available in at least one region of the country is not a good situation for DIYers and contractors. Nonetheless, these untreated surfaces along the ripped edges are a durability concern and still may require treatment per the manufacturerвЂ™s product warranty. While the 2015 IRC and earlier editions require field-cut ends, notches, and drilled holes of preservative-treated wood to be treated in the field in accordance with AWPA M4 (2015 IRC R317.1.1), the language does not cite вЂњedgesвЂќ for field treatment. The second problem is that ripping treated lumber exposes at least one and in some cases two largely untreated surfaces. As anyone who has ever shattered a baseball bat can tell you, localized grain deviations are hard to detect and can greatly impact strength. Stress-grading is more than just the number and size of the knots it also takes into consideration other factors, such as slope of grain. For example, if three 2x2 pieces are made from a 2ењ† and regraded by an experienced grader, one 2x2 might be graded as вЂњcull,вЂќ the next as No. 2, does not carry over to the individual pieces that result from ripping. The first problem is that the grade of a piece of lumber, such as a 2ењ† No. Neither the measured nor the tag dimensions conform to the nominal dimensions of a 2x2 specified in the 2015 IRC. Typical of commercially available stress-rated pressure-treated 2x2 southern pine, this nominal 2x2 purchased at a lumberyard measures 1вЂ‰3/8 inches by 1вЂ‰3/8 inches, while the treatment tag reads 1.3125 inches by 1.3125 inches. 2 SP) to the correct 2x2 dimension, but ripping creates two technical problems. One solution is to rip larger sizes of treated 2-by stress-rated material (such as PT No. Thus, under the previous IRC editions, contractors were faced with a supply issue. But according to information from three SP lumber inspection agencies- Southern Pine Inspection Bureau, Timber Products, and RRA/Southeastern Lumber ManufacturerвЂ™s Association-as well as our own observations at big-box lumber outlets, stress-rated nominal 2x2 pressure-treated (PT) lumber has not been available in the marketplace for a number of years. Practical IssuesДЄs a practical matter, ledger strips used outdoors are required to be pressure treated, typically southern pine (SP) in the mid-Atlantic and Southeast. But now builders commonly use joist hangers, and while ledger strips are still OK to use in interior applications, the 2018 edition of the IRC no longer permits their use on exterior decks (2018 IRC R507.6.1). Before joist hangers became widely available, ledger strips were commonly used to help support toe-nailed joists, whether the joists were hung from an interior rim joist or flush beam or from an exterior deck ledger.