Page 248 - The Engineering Guide to LEED-New Construction Sustainable Construction for Engineers

LEED Materials and Resour ces 221

(such as a steel beam) or an assembly (such as a prebuilt window unit). The value
determination is made on a mass percent basis. So for any item the following can be defined:
MASS Mass (weight) of the regional portion of unit i
REGi
MASS Total mass (weight) of unit i
UNITi
MATL$ Total cost of unit i
UNITi
MATL$ Value of the regional portions of unit i
REGi
The value of the regional portions for each individual unit i can be determined from the
following:

MATL$ = MATL$ (MASS )/MASS (5.5.3)
REGi UNITi REGi UNITi
And, in a similar manner, the total values of the regional portions needed in Eqs. (5.5.1)
and (5.5.2) can be determined from the summation of the individual unit contributions
as follows:
MATL$ =∑ MATL$ over all units i (5.5.4)
REG REGi
Special Circumstances and Exemplary Performance (LEED 2009 MRc5)
Since it is usually not certain during the design phase of the exact amounts of regional
items or content that might be purchased, this subcategory is listed as a construction
phase submittal. The contractor should keep records of the locations of extraction,
processing, and manufacturing.
Any materials used for obtaining the points in this category can also be used for MR
subcategories 3 (Materials Reuse), 4 (Recycled Content), 6 (Rapidly Renewable Materials),
and 7 (Certified Wood).
An additional EP point can be earned for regional content if the following is true:
100(MATL$ )/MATL$ ≥ 40 (5.5.5)
REG T
The equations for this credit subcategory are summarized in Tables 5.5.1 and 5.5.2.

Regional Content Value Total Regional Content
of Unit i (MATL$ ) Value (MATL$ )
REGi REG
Equations MATL$ (MASS )/MASS ∑MATL$ over all units i
UNITi REGi UNITi REGi
TABLE 5.5.1 Summary of Regional Materials Value Equations

Worth Criterion
MRc5 (MRc5.1 in LEED 2.2) 1 point 100(MATL$ )/MATL$ ≥ 10
REG T
MRc5 (MRc5.2 in LEED 2.2) 1 additional point 100(MATL$ )/MATL$ ≥ 20
REG T
Exemplary performance 1 point in addition to MRc5 100(MATL$ )/MATL$ ≥ 30 ∗
REG T
∗ LEED 2.2 had 40 percent compliance for the EP point.

TABLE 5.5.2 Regional Materials Compliance Equation Summary LEED 2009