- Q. Can I use laminated veneer lumber for stair carriage material? Since it doesn’t shrink, it seems it would solve many of the problems associated with the shrinkage of sawn lumber stringers.
A.Curtis Eck, P.E., responds: LVL should work fine for stair carriages in most cases, but you should check with the manufacturer before cutting. Because LVL is intended primarily for use as a beam, manufacturers often warn against notching. Otherwise, it has not only the advantage you mention, but also superior strength. And because LVL is available in wider sizes than dimensional lumber, it may be useful, if sized correctly, for longer stair spans than sawn stringers can safely handle.
The engineered lumber manufacturer can help you select the best product for a stair application. For example, in addition to Microllam LVL, my company, Trus Joist MacMillan, also makes Timberstrand LSL (laminated strand lumber). LSL is less expensive than LVL, is easy to cut, and has great resistance to nail splitting. To assist builders, Trus Joist MacMillan has just introduced a stringer sizing chart that specifies minimum throat depths and allowable stair spans for Timberstrand stringers. For a copy, call 800/628-3997.
Curtis Eck is a Seattle-based technical representative for Trus Joist MacMillan.
