IMPACT OF BUILDING'S LIFESPAN ON THE LIFE CYCLE ASSESSMENT Karel STRUHALA, Zuzana STRÁNSKÁ Faculty of Civil Engineering, Brno University of Technology, struhala.k@fce.vutbr.cz

Introduction - Objectives Objectives of the assessment Evaluation of environmental impacts of selected building‘s life cycle Comparison of results in regard to varying service life lengths (50-100 years) 5-year steps Total results and annual results per per 1m2 of building‘s area Comparison of four service life scenarios Three scenarios include repairs and renovations One scenario with varying occupancy

Introduction – Assessed Building General information Two-storey detached house without basement Net floor area 105.55 m2 Four tenants (according to designs) Building site located in Eastern Bohemia Structures Reinforced concrete foundations insulated with XPS External Walls and roof made of SIPs (Structural Insulated Panels) insulated with mineral wool Interior walls made of SIPs with plasterboard cladding Floor made of timber beams and OSB boards with plasterboard cladding Plastic doors and windows with double or triple glazing

Introduction – Assessed Building Equipment Heating and DHW – gas fireplace/boiler Mechanical ventilation – central ventilation unit, plastic ducts Sanitary equipment – common equipment (shower, bathtub, sink, etc.); no water conservation measures No renewable energy sources Designed annual energy and water consumption and waste production (4 tenants) 70.0 GJ of natural gas 5.76 GJ of electric energy 58.4 m3 of water 790 kg of municipal waste

Methodology and Tools Life Cycle Assessment (LCA) System boundaries Based on ISO 14040 and following standards (especially EN 15978) The EN 15978 divides a building’s life cycle into four stages and 16 modules: Product stage – modules A1 to A3 Construction stage – modules A4 and A5 Use stage – modules B1 to B7 End of life stage – modules C1 to C4 System boundaries Cradle-to-Grave system boundaries – modules A1 to C4 according to EN 15978, excluding module B5 Refurbishment The amounts of materials, energy, etc. are based on the design documentation Only the building and processes directly connected with it and its use are included in the assessment – e.g. the landscaping is not included

Methodology and Tools Characterization model The results are calculated using CML2001 (version November 2010) characterization factors Normalization CML 2001 EU 25 (version November 2010) is used to simplify the comparison of results of individual scenarios Results in seven out of 12 available impact categories are presented – those required by EN 15978: Abiotic depletion (ADP elements) Abiotic depletion (ADP fossil) Acidification Potential (AP) Eutrophication Potential (EP) Global Warming Potential (GWP) Ozone Layer Depletion Potential (ODP) Photochemical Ozone Creation Potential (POCP)

Methodology and Tools Tools and databases GaBi 4 tool Ecoinvent 2.0 database Some simplifications and estimations had to be made due to the lack of suitable data in the design or in the database – especially in regard to the construction and deconstruction processes and waste management Some materials are not included in the database. Two or more individual processes are used to represent them Energy and water consumption during the construction of the building (module A5 according to EN 15978) were estimated based on the consultations with the builder Waste management scenario (landfilling) is based on information about waste management in Czech Republic (Czech Environmental Information Agency; 2015)

Assessed Scenarios Series of four scenarios consecutive scenarios is compared and evaluated S1 – “Erroneous” reference scenario Includes the production of materials and construction of the building (modules A1 to A5) Use of the building is insufficiently addressed – a common mistake in design of buildings as well as in LCAs Modules B3 Repair, B4 Replacement and B5 Refurbishment are not included Energy and water consumption and waste production are constant, corresponding with designed occupancy (four tenants) End of life scenario includes demolition and landfilling

Assessed Scenarios S2 – “Proper” reference scenario Includes the production of materials and construction of the building (modules A1 to A5) Use of the building includes repairs and replacement of structures and equipment E.g. estimated service life of the ventilation unit is 20 years Energy and water consumption and waste production are constant, corresponding with designed occupancy (four tenants) End of life scenario includes demolition and landfilling

Assessed Scenarios S3 – Neglected maintenance scenario Includes the production of materials and construction of the building (modules A1 to A5) Use of the building includes repairs and replacement of structures and equipment E.g. estimated service life of the ventilation unit is 20 years Scenario expects that the tenants would neglect the maintenance of the building and equipment. This is represented by increasing energy consumption (e.g. due to worsening efficiency of the boiler or failure) Energy and water consumption and waste production are constant, corresponding with designed occupancy (four tenants) End of life scenario includes demolition and landfilling

Assessed Scenarios S4 – Neglected maintenance and varying occupancy scenario Includes the production of materials and construction of the building (modules A1 to A5) Use of the building includes repairs and replacement of structures and equipment E.g. estimated service life of the ventilation unit is 20 years Scenario expects that the tenants would neglect the maintenance of the building and equipment. This is represented by increasing energy consumption (e.g. due to worsening efficiency of the boiler) Energy and water consumption and waste production are fluctuating (estimated) due to varying occupancy – between two and four tenants in time End of life scenario includes demolition and landfilling

Assessed Scenarios Varying occupancy in S4 scenario

Assessed Scenarios Heating energy consumption comparison of all scenarios

Results Total environmental impacts per 1 m2 of net floor area 50-year building’s service life Impact cat. Scenario S1 Scenario S2 Scenario S3 Scenario S4 Unit ADP elements 8,47E-03 1,21E-02 1,22E-02 kg Sb-Eq.·m-2 ADP fossil 7,30E+01 7,65E+01 7,83E+01 MJ·m-2 AP 7,70E+00 8,68E+00 8,84E+00 8,78E+00 kg SO2-Eq.·m-2 EP 4,76E+00 4,89E+00 4,93E+00 3,94E+00 kg Phos.-Eq.·m-2 GWP 3,59E+03 3,80E+03 3,96E+03 3,88E+03 kg CO2-Eq.·m-2 ODP 1,76E-03 3,05E-03 3,07E-03 kg R11-Eq.·m-2 POCP 1,25E+00 1,37E+00 1,41E+00 1,39E+00 kg Eth.-Eq.·m-2 100-year building’s service life Impact cat. Scenario S1 Scenario S2 Scenario S3 Scenario S4 Unit ADP elements 1,04E-02 2,50E-02 2,52E-02 2,51E-02 kg Sb-Eq.·m-2 ADP fossil 1,36E+02 1,50E+02 1,55E+02 1,54E+02 MJ·m-2 AP 1,25E+01 1,64E+01 1,68E+01 1,67E+01 kg SO2-Eq.·m-2 EP 8,83E+00 9,46E+00 9,54E+00 7,60E+00 kg Phos.-Eq.·m-2 GWP 7,11E+03 7,94E+03 8,38E+03 8,18E+03 kg CO2-Eq.·m-2 ODP 2,16E-03 6,06E-03 6,13E-03 6,12E-03 kg R11-Eq.·m-2 POCP 2,03E+00 2,49E+00 2,59E+00 2,55E+00 kg Eth.-Eq.·m-2

Results Total environmental impacts per 1 m2 of net floor area 50-year building’s service life Impact cat. Scenario S1 Scenario S2 Scenario S3 Scenario S4 Unit ADP elements 8,47E-03 1,21E-02 1,22E-02 kg Sb-Eq.·m-2 ADP fossil 7,30E+01 7,65E+01 7,83E+01 MJ·m-2 AP 7,70E+00 8,68E+00 8,84E+00 8,78E+00 kg SO2-Eq.·m-2 EP 4,76E+00 4,89E+00 4,93E+00 3,94E+00 kg Phos.-Eq.·m-2 GWP 3,59E+03 3,80E+03 3,96E+03 3,88E+03 kg CO2-Eq.·m-2 ODP 1,76E-03 3,05E-03 3,07E-03 kg R11-Eq.·m-2 POCP 1,25E+00 1,37E+00 1,41E+00 1,39E+00 kg Eth.-Eq.·m-2 22.92% increase 100-year building’s service life Impact cat. Scenario S1 Scenario S2 Scenario S3 Scenario S4 Unit ADP elements 1,04E-02 2,50E-02 2,52E-02 2,51E-02 kg Sb-Eq.·m-2 ADP fossil 1,36E+02 1,50E+02 1,55E+02 1,54E+02 MJ·m-2 AP 1,25E+01 1,64E+01 1,68E+01 1,67E+01 kg SO2-Eq.·m-2 EP 8,83E+00 9,46E+00 9,54E+00 7,60E+00 kg Phos.-Eq.·m-2 GWP 7,11E+03 7,94E+03 8,38E+03 8,18E+03 kg CO2-Eq.·m-2 ODP 2,16E-03 6,06E-03 6,13E-03 6,12E-03 kg R11-Eq.·m-2 POCP 2,03E+00 2,49E+00 2,59E+00 2,55E+00 kg Eth.-Eq.·m-2

Results Total environmental impacts per 1 m2 of net floor area 50-year building’s service life Impact cat. Scenario S1 Scenario S2 Scenario S3 Scenario S4 Unit ADP elements 8,47E-03 1,21E-02 1,22E-02 kg Sb-Eq.·m-2 ADP fossil 7,30E+01 7,65E+01 7,83E+01 MJ·m-2 AP 7,70E+00 8,68E+00 8,84E+00 8,78E+00 kg SO2-Eq.·m-2 EP 4,76E+00 4,89E+00 4,93E+00 3,94E+00 kg Phos.-Eq.·m-2 GWP 3,59E+03 3,80E+03 3,96E+03 3,88E+03 kg CO2-Eq.·m-2 ODP 1,76E-03 3,05E-03 3,07E-03 kg R11-Eq.·m-2 POCP 1,25E+00 1,37E+00 1,41E+00 1,39E+00 kg Eth.-Eq.·m-2 22.92% increase 111.50% increase 100-year building’s service life Impact cat. Scenario S1 Scenario S2 Scenario S3 Scenario S4 Unit ADP elements 1,04E-02 2,50E-02 2,52E-02 2,51E-02 kg Sb-Eq.·m-2 ADP fossil 1,36E+02 1,50E+02 1,55E+02 1,54E+02 MJ·m-2 AP 1,25E+01 1,64E+01 1,68E+01 1,67E+01 kg SO2-Eq.·m-2 EP 8,83E+00 9,46E+00 9,54E+00 7,60E+00 kg Phos.-Eq.·m-2 GWP 7,11E+03 7,94E+03 8,38E+03 8,18E+03 kg CO2-Eq.·m-2 ODP 2,16E-03 6,06E-03 6,13E-03 6,12E-03 kg R11-Eq.·m-2 POCP 2,03E+00 2,49E+00 2,59E+00 2,55E+00 kg Eth.-Eq.·m-2

Results Normalized environmental impacts of Scenario S4 of the building’s service life per 1 m2 of net floor area in 5-year steps Whole Life-Cycle Use stage

Results Normalized environmental impacts of the building’s service life per 1 m2 of net floor area in 5-year steps

Conclusion Length of the service life has an impact on both total and annual environmental impacts Omitting repair and replacement scenarios in a building LCA can lead to underestimated results. In case of the assessed building the difference reached up to 22%. The designed (full) occupancy of the building has slightly higher environmental impacts than “real” occupancy. In case of the assessed building the difference was approximately 5%.

Thank you for your attention Feel free to ask any questions or write me an e-mail to struhala.k@fce.vutbr.cz