process. The automation of information transfer from external data sources to BIM
is one of the current challenges that BIM-LCA integration has to face.
Ongoing research shows that ventilation systems can contribute significantly to
increase GHGs emissions, especially considering that these systems do not always
work properly from the start, and faulty equipment must be replaced, thus generating additional emissions through materials and labour. The presentation showed
that, given the role they play in buildings performances, embodied impacts of
ventilation systems should be reduced, via increased recycled and recyclable
materials content, and taking into account also alternative ventilation methods like
hybrid natural ventilation.
The “early BIM” approach presented by Alexander Hollberg raised a lot of
interest in the audience. A question was asked about the comparison between the
impacts of a building where environmentally sound decisions are taken at the early
stage and one where these decisions are taken only at later stages of the design. The
comparison has not been done so far by the authors, but the same systems
boundaries were used in the early stages as they would apply to later stages. As
pointed out by one of the attendees, the approach presented is similar to the one
taken by other tools used for LCA in building design, especially Tally
TM . However,
as Alexander Hollberg highlighted, the main difference lays in the full integration
into the design process. Their approach provides instant feedback while changing
parameters, which is a unique feature in the current state of the art. Furthermore,
they combine operational energy demand calculation and the embodied impact
calculation in one method. This kind of approach appeared slightly different from a
“conventional” BIM approach. The authors call it “early BIM”, because they link
information to the geometric 3D model. Conventional BIM, such as Revit models,
contain more detailed information stored in the 3D model. This results in a more
complex model which cannot be adapted as quickly as simple 3D models.
Therefore, they use the simple models in early stages, which can then ideally be
enriched with detailed information throughout the design process.
The topics discussed by Adélaïde Mailhac gave an interesting overview of the
potential of BIM use in an LCA framework, explaining that BIM can be used in
every phase of the LCA, not just in the early conception stage. However, data
availability in the right format (e.g. CityGML compliant data) still remains a
problem, since data is not provided easily by every actor, public or private.
Finally, the approach presented by Özge Yılmaz intrigued the audience due to its
modular structure, which integrates different approaches. It also raised concerns
about the seamless incorporation of ABM, which is a dynamic simulation tool, with
a rather static LCA approach. The presenter recognized that LCA provides a
snap-shot of environmental impacts over a given period of time and a shift from
static LCA to more dynamic LCA is certainly necessary for successful integration
of ABM and LCA. A second observation concerned the suggestion to include not
only the behavioural patterns, but also consumption patterns in the ABM simulations. This aspect will be taken into account in conjunction with an urban metabolism approach within the Nature4Cities project.
LCM at the Urban Scale: BIM and Nature Based Solutions
265
is one of the current challenges that BIM-LCA integration has to face.
Ongoing research shows that ventilation systems can contribute significantly to
increase GHGs emissions, especially considering that these systems do not always
work properly from the start, and faulty equipment must be replaced, thus generating additional emissions through materials and labour. The presentation showed
that, given the role they play in buildings performances, embodied impacts of
ventilation systems should be reduced, via increased recycled and recyclable
materials content, and taking into account also alternative ventilation methods like
hybrid natural ventilation.
The “early BIM” approach presented by Alexander Hollberg raised a lot of
interest in the audience. A question was asked about the comparison between the
impacts of a building where environmentally sound decisions are taken at the early
stage and one where these decisions are taken only at later stages of the design. The
comparison has not been done so far by the authors, but the same systems
boundaries were used in the early stages as they would apply to later stages. As
pointed out by one of the attendees, the approach presented is similar to the one
taken by other tools used for LCA in building design, especially Tally
TM . However,
as Alexander Hollberg highlighted, the main difference lays in the full integration
into the design process. Their approach provides instant feedback while changing
parameters, which is a unique feature in the current state of the art. Furthermore,
they combine operational energy demand calculation and the embodied impact
calculation in one method. This kind of approach appeared slightly different from a
“conventional” BIM approach. The authors call it “early BIM”, because they link
information to the geometric 3D model. Conventional BIM, such as Revit models,
contain more detailed information stored in the 3D model. This results in a more
complex model which cannot be adapted as quickly as simple 3D models.
Therefore, they use the simple models in early stages, which can then ideally be
enriched with detailed information throughout the design process.
The topics discussed by Adélaïde Mailhac gave an interesting overview of the
potential of BIM use in an LCA framework, explaining that BIM can be used in
every phase of the LCA, not just in the early conception stage. However, data
availability in the right format (e.g. CityGML compliant data) still remains a
problem, since data is not provided easily by every actor, public or private.
Finally, the approach presented by Özge Yılmaz intrigued the audience due to its
modular structure, which integrates different approaches. It also raised concerns
about the seamless incorporation of ABM, which is a dynamic simulation tool, with
a rather static LCA approach. The presenter recognized that LCA provides a
snap-shot of environmental impacts over a given period of time and a shift from
static LCA to more dynamic LCA is certainly necessary for successful integration
of ABM and LCA. A second observation concerned the suggestion to include not
only the behavioural patterns, but also consumption patterns in the ABM simulations. This aspect will be taken into account in conjunction with an urban metabolism approach within the Nature4Cities project.
LCM at the Urban Scale: BIM and Nature Based Solutions
265