177
provide results for this stage, Athena has the option to include them, and Tally automatically adds them in. However, they are not frequently included in LCA studies
due to the lack of consensus on how to calculate and integrate the results to the study
(De Wolf et al. 2017).
9.1.1 Functionality of LCIA Tools
In order to best understand the trends in the results, LCA studies were carried out
for discrete components of the MIA and compared at the level of a single building
construction rather than a whole building. The structure, roof construction, exterior
wall, and interior wall finishes were all analyzed separately, with different material
choices, to compare results. The three structural systems studied were a concrete
frame, a steel frame, and a wood frame. The concrete structure includes six concrete
footings, a concrete slab on grade, six 8″ square concrete columns, and two 12″
concrete floor slabs. The steel structure includes six concrete footings, a concrete
slab on grade, six W10×33 steel columns, 14 W12×26 steel beams, and two floor
slabs made up of a 2″ concrete slab over 3″ metal decking. The wood structure
includes six concrete footings, a concrete slab on grade, six 6.75″ × 7.5″ glulam
columns, 14 6.75″ × 7.5″ glulam beams, and two floor slabs made up of a 2″ concrete topping over 5″ CLT plank.
Seven different exterior wall constructions were studied, all with differing
R-values. The FU for the wall study was 147′ × 22′, or 3234 sf, of wall. The wall
constructions tested are a CMU wall, a precast concrete wall, a masonry wall, brick
cladding over a metal stud wall, steel panels over a metal stud wall, brick cladding
on a CMU wall, and wood siding on a wood stud wall. Five different interior wall
finishes were studied. They were painted gypsum, painted gypsum with furring
channels, wall tiles, wall tiles over furring channels, and plaster over metal lath.
This study looked at the trends between different material choices for one building
construction using Athena, Tally, and One Click LCA.
Based on the nature of the way that Athena collects information about the project
materials being used, it is not possible to fully isolate these studies. Athena uses the
major assembly groups to input information about a project and hosts secondary
information within them. To get information on just the roof construction and wall
finishes from Athena, a model with the host component, either the roof slab or wall,
was used. Results were calculated with and without the added “envelope” construction in each case, and the difference in the results reveals the impacts of just the
envelope component. Tally and One Click LCA have more flexibility to isolate individual components and run an LCA study on a discrete part. Anything that can be
modeled in Revit can be the object of study in Tally and One Click LCA. The roof
construction and wall finishes were modeled as independent families, and the study
was conducted on the isolated construction.
9.1 The MIA
provide results for this stage, Athena has the option to include them, and Tally automatically adds them in. However, they are not frequently included in LCA studies
due to the lack of consensus on how to calculate and integrate the results to the study
(De Wolf et al. 2017).
9.1.1 Functionality of LCIA Tools
In order to best understand the trends in the results, LCA studies were carried out
for discrete components of the MIA and compared at the level of a single building
construction rather than a whole building. The structure, roof construction, exterior
wall, and interior wall finishes were all analyzed separately, with different material
choices, to compare results. The three structural systems studied were a concrete
frame, a steel frame, and a wood frame. The concrete structure includes six concrete
footings, a concrete slab on grade, six 8″ square concrete columns, and two 12″
concrete floor slabs. The steel structure includes six concrete footings, a concrete
slab on grade, six W10×33 steel columns, 14 W12×26 steel beams, and two floor
slabs made up of a 2″ concrete slab over 3″ metal decking. The wood structure
includes six concrete footings, a concrete slab on grade, six 6.75″ × 7.5″ glulam
columns, 14 6.75″ × 7.5″ glulam beams, and two floor slabs made up of a 2″ concrete topping over 5″ CLT plank.
Seven different exterior wall constructions were studied, all with differing
R-values. The FU for the wall study was 147′ × 22′, or 3234 sf, of wall. The wall
constructions tested are a CMU wall, a precast concrete wall, a masonry wall, brick
cladding over a metal stud wall, steel panels over a metal stud wall, brick cladding
on a CMU wall, and wood siding on a wood stud wall. Five different interior wall
finishes were studied. They were painted gypsum, painted gypsum with furring
channels, wall tiles, wall tiles over furring channels, and plaster over metal lath.
This study looked at the trends between different material choices for one building
construction using Athena, Tally, and One Click LCA.
Based on the nature of the way that Athena collects information about the project
materials being used, it is not possible to fully isolate these studies. Athena uses the
major assembly groups to input information about a project and hosts secondary
information within them. To get information on just the roof construction and wall
finishes from Athena, a model with the host component, either the roof slab or wall,
was used. Results were calculated with and without the added “envelope” construction in each case, and the difference in the results reveals the impacts of just the
envelope component. Tally and One Click LCA have more flexibility to isolate individual components and run an LCA study on a discrete part. Anything that can be
modeled in Revit can be the object of study in Tally and One Click LCA. The roof
construction and wall finishes were modeled as independent families, and the study
was conducted on the isolated construction.
9.1 The MIA