Don’t overlook wood doors as there are quite a few credits that can be had if you specify the proper material. Here’s a brief overview of materials and their corresponding credit:
- Particleboard core: the standard solid-core material offers MR4, and can provide credit for MR5 if your project is within 500 miles of the door manufacturer. Specifying UF-free particleboard will lend to EQ4.4 in addition to MR4. FSC-certified particleboard offers MR7 credit in addition to MR4 and EQ4.4, while being a lower-cost alternative to glued-block cores (which are the other means of reaching MR7).
- Structural Composite Lumber (SCL): flush door manufacturers moved to SCL (think Timberstrand®) material in the 90’s as an alternative to glued-block cores. This core will also provide more capability in offering warranties with lite cutouts due to its strength (which, in addition to the material’s stability, was the initial reason for incorporating SCL into door cores). Since this material is made from virgin material, SCL does not offer MR credits, but does offer EQ4.4 due to the use of MDI (diphenylmethane diisocyanate) resins, which do not off gas formaldehyde or other contaminants, despite the scariness of the name.
- Agrifiber: a relative newcomer to door cores, this core can be made from wheatstraw, soybean stalks, or other agricultural waste as the name implies. In addition to being strong and meeting Grade 1 LD-2 standards, Agrifiber contributes to MR4, and EQ4.4 credits. Agrifiber contributes to MR6 Rapidly Renewable Material, a difficult credit to achieve.
- Stave Lumber: prior to the advent of SCL cores, stave lumber cores or SLC (don’t confuse the two!) was the “heavy duty” core and the choice of many institutional users. Today, with the development of more engineered lumber choices, this core has all but gone by the wayside, unless you are attempting to meet MR7 Certified Wood credits, as FSC chain of custody can be provided on stave lumber material. For a list of FSC Chain of Custody members, click here. SLC doesn’t emit any contaminants, so this core meets EQ4.4.
Of course, what good would a discussion on wood door comparisons be without some pricing guidelines? Using particleboard as a baseline, here are the pricing comparisons:
- Particleboard
- UF-free particleboard + 15%
- FSC certified particleboard +20%
- Agrifiber +25%
- Structural Composite Lumber (SCL) +30%
- FSC certified Stave Lumber Core (SLC) +45%
One point of caution: to get the coveted MR6 Rapidly Renewable credit, materials meeting this criteria must be 2.5% of the value of all building materials in your project to get the credit. We would like to see this threshold modified lower to make this credit reachable, but that’s another discussion. Still, the Agrifiber product offers plenty to consider on your next project, be it in doors or cabinetry. Hopefully, this discussion will help you get the most “bang for your buck” when considering LEED credits, at least as doors are concerned. Please feel free to contact us to discuss further!
Doors & Door Hardware 