Su Re En Ma Ho — Central Europe

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Central Europe experience and knowledge about sustainable rehabilitation of housings and energy management 1. Social background and expectations 2. Overview about reached rehabilitation status 3. Expected transitions (shifts)

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte 1. Social background and expectations - europe-wide the operation of buildings count for round about 40% of the final energy consumption - in Germany round about 30% of the final energy consumption is related to housing - round about 80% of this energy is needed for heating (warm water, cooking, ligthning, and so on is the rest)

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Generally mind-set of dweller concerning rehabilitation [1]: good very good Ex ante in between ex post retrospective questioning

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Generally mind-set of dweller concerning rehabilitation [1]: Advantages: ? Disadvantages/Burden: - construction site dirt site noise constriction in using the rooms untidiness enduring presence of craftsman insufficient information about coordination, kind amount of rehabilitation workflow

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Expectations of dwellers [1]: Improvement of the residential building CO 2 reduction Increasement of comfort of living energy saving Improvement of the building climate Reduction of heating costs very important not important at all 5

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Age structure of buildings respectively flats [2]: buildings flats 6

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Ownership conditions [2]: buildings dwellings % % Private ownership 88. 3 62. 4 Community of owners 5. 5 15. 6 Housing company 5. 5 20. 7 others 0. 7 1. 2 private 95. 9 95. 2 Community of owners 2. 8 3. 5 Housing company 0. 8 private 50. 9 33. 0 Community of owners 18. 5 26. 5 Housing company 28. 7 38. 7 All buildings One and two family houses Multi family houses 7

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Building size and floor numbers [2]: One and two family houses Share of buildings in % One dwelling 73. 0 Two dwellings 27. 0 One floor 39. 2 Two floors 55. 7 More then two floors 5. 1 Multi family houses 3 – 4 dwellings 53. 7 5 – 6 dwellings 18. 6 7 – 12 dwellings 19. 0 More then 12 dwellings 8. 8 1 – 2 floors 41. 3 3 – 4 floors 51. 1 5 – 9 floors 7. 3 More then 9 floors 0. 3 8

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Heat insulation status [2]: Buildings (%) with insulation of Exterior walls Roof / upper floor ceiling Basement ceiling / ground floor All buildings 42. 1 76. 4 37. 1 Old buildings constructed before 1978 35. 7 68. 2 23. 3 Year of construction 1979 2004 53. 2 92. 1 62. 1 New buildings constructed after 2005 66. 0 98. 5 87. 3 9

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Heat insulation status [2]: ex post insulation Buildings (%) with insulation of Exterior walls Roof / upper floor ceiling Basement ceiling / ground floor All buildings 42. 1 76. 4 37. 1 Old buildings constructed before 1978 35. 7 68. 2 23. 3 Year of construction 1979 2004 53. 2 92. 1 62. 1 New buildings constructed after 2005 66. 0 98. 5 87. 3 Buildings (%) with ex post insulation of Exterior walls Roof / upper floor ceiling Basement ceiling / ground floor All buildings 20. 8 40. 5 9. 5 Old buildings constructed before 1978 27. 6 52. 2 12. 5 10

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Ex post insulation of multi family houses constructed before 1978 [2]: geographical differences Multi family houses (%) with es post insulation of Exterior walls Roof / upper floor ceiling Basement ceiling / ground floor Northern parts of Germany 22. 5 42. 4 6. 8 Southern parts of Germany 21. 2 43. 0 8. 7 Formerly GDR 39. 5 64. 9 22. 3 11

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Exterior walls: kind of wall construction in % [2] Kind of wall construction whole Germany north south east brick, one layer 61. 3 32. 4 85. 1 63. 4 brick, two layers 29. 9 61. 2 6. 5 21. 5 truss wall 3. 1 2. 4 2. 9 4. 9 timber frame construction 3. 7 3. 3 4. 3 3. 2 concrete, prefabricated elements 1. 9 0. 7 1. 0 6. 7 Kind of wall construction before 1978 1979 - 2004 2005 until now brick, one layer 63. 8 56. 0 57. 5 brick, two layers 28. 7 32. 8 27. 8 truss wall 4. 4 0. 6 timber frame construction 1. 5 7. 5 13. 0 concrete, prefabricated elements 1. 5 3. 1 0. 8 12

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Insulation thickness (exterior walls) [2]: All Old buildings before 1978 Between 1979 and 2004 New buildings after 2004 percentage Insulation thickness 13

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Insulation thickness (exterior wall, old buildings before 1978) [2]: All old buildings Constructed with insulation Ex post insulation percentage Insulation thickness 14

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Insulation thickness (exterior wall, old buildings before 1978) [2]: Brick, one layer Brick, two layers Truss wall percentage Prefabricated concrete elements Insulation thickness 15

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Thickness of upper floor ceiling / roof insulation[2]: All housing buildings Old buildings before 1978 Buildings from 1979 – 2004 New buildings from 2005 to no percentage Insulation thickness 16

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Ex post insulation thickness of roof / upper floor ceiling (old buildings before 1978) [2]: Roof not heated Roof heated percentage Insulation thickness 17

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Insulation thickness of ground floor / basement ceiling [2]: percentage All housing buildings Old buildings before 1978 Buildings from 1979 – 2004 New buildings from 2005 to now Insulation thickness 18

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Height of the basement [2] (old buildings before 1978): percentage High basement (a person 1. 80 m tall can use it erectly) 75. 9 Low basement (a person 1. 80 m tall can use it barely) 19. 3 Very low basement (a person 1, 80 m tall have to crouch down) 4. 8 Heating situation in the basement [2] (old buildings before 1978): Percentage No basement 12. 6 Not heated basement 61. 9 Partly heated basement 22. 2 Completely heated basement 3. 3 19

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Frequency distribution of window age [2]: All buildings Old buildings before 1979 percentage Installation age 20

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Thermal insulation glass production in Germany [2]: Triple glazing (U=0. 7 W/m 2 K) Duplex glazing (U=1. 1 W/m 2 K) Duplex glazing (U=1. 2 W/m 2 K) Duplex glazing (U=1. 4 W/m 2 K) 21

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Kind of glazing and window installation year [2]: All buildings Old buildings before 1978 New buildings from 2005 until now Windows installed before 1994 Single glazing 2. 2 4. 1 Douplex glazing 41. 2 56. 8 Trippel glazing 0. 5 0. 4 Single glazing 0. 3 0. 2 0. 3 Douplex glazing 52. 6 36. 4 85. 0 Tripel glazing 3. 2 2. 0 14. 7 sum 100 100 Windows installed after 1995 22

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Kind of heating and energy source [2]: Old buildings before 1978 Buildings from 1979 until 2004 New buildings after 2004 district heating 3. 9 4. 0 3. 6 central heating 79. 9 92. 4 92. 2 seperate dwelling heating 6. 3 1. 5 1. 6 individual room heating 9. 9 2. 1 2. 5 district heating 3. 9 4. 0 3. 6 gas 47. 9 59. 8 60. 1 oil 37. 2 29. 4 5. 9 biomass 6. 5 2. 6 9. 2 coal 1. 0 0. 0 electricity 3. 5 4. 3 21. 1 Kind of heating Kind of energy source 23

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Amount of modernisation (year of construction before 2004) [2]: Number of energy saving measures Percentage Only one energy saving measure 66. 4 Two energy saving measures 20. 9 Three energy saving measures 6. 4 Four energy saving measures 4. 2 Five energy saving measures 1. 9 Six energy saving measures 0. 3 100 24

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Amount of energetically rehabilitation intentions during the next five years [2]: Intention All buildings Old buildings before 1978 Exterior wall insulation 7. 5 9. 6 Roof or upper floor ceiling insulation 8. 5 11. 0 Basement ceiling or ground floor insulation 3. 7 5. 0 Installation of new windows 7. 5 9. 5 Installation of photovoltaic elements 2. 5 1. 9 Installation of solar heating elements 4. 7 4. 3 Installation of district heating connection 0. 1 Replacement of the heating system 10. 2 10. 4 25

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte 3. Expected Transitions Thinking about energy demand or energy consumption calculation in a different way as it is done today - by establishing such calculations as a sustainability criteria, - integrating user/owner behaviour an consider this as an important aspect, - combining energy calculation with economical calculations (costs, value, finance) and - establishing new policy instruments if they are more effective. 26

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte In Germany nowadays used energy certificate: 27

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte But, what's the real situation (1)? Measured energy consumption in k. Wh/(m 2 a) Calculated energy demand in k. Wh/(m 2 a) 28

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte But, what's the real situation (2)? Low energy housing district Niedernhausen Measured energy consumption per m² in 1994 heating energy average 29

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte European and German climate protection and energy saving goals - goals 2020 (European council, March 2007) - 20 % reduction in green house gases compared to 2005 - 20 % share of renewable energy - 20 % reduction of the energy consumption - goals of the German government until 2050 (German energy concept 2011) - 80 % reduction of green house gases - 50 % reduction of the primary energy consumption - 25 % reduction of the electrical power consumption (wattage, end energy) - 40 % reduction of the traffic related energy consumption - 80 % reduction of the head demand of buildings - 60 % share of renewable energy of the energy consumption (end energy) - 80 % share of renewable energy of the electrical power consumption (gross value) 30

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Some statistical data (Germany 2009, Federal Ministry of Economics and Technology): First orientation: Total primary energy consumption: 13, 300 PJ/year = 163 GJ/(capita·year) = 5, 170 W/capita Head energy consumption (private households): GJ/(capita·year) = W/capita 2, 300 PJ/year = 28 900 Can you imagine 900 W? 31

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Architects and engineers are not so familiar with this 900 W/inhabitant Their key number is something in k. Wh/(m 2∙year): Total amount of head floor space (only residential buildings): 34. 85 Gm 2 This lead to annually: 2, 300 PJ/34. 85 Gm 2 = 660 MJ/m 2 or with 365∙ 24∙ 3600 = 31, 536, 000 seconds per year to 660 MJ/(m 2∙ 31, 536, 000 s) = 20. 9 W/m 2. One year is equal to 8, 760 h so that there is an average head energy consumption of: 20. 9 W/m 2∙ 8, 760 h/year = 183, 084 W∙h/(m 2·year) = 183 k. Wh/(m 2·year). 32

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte German Goal: 80 % reduction Target value for 2050: average head energy consumption: 0. 2∙ 183 k. Wh/(m 2∙year) = 36. 6 k. Wh/(m 2∙year) or: 0. 2∙ 900 W/inhabitant = 180 W/inhabitant (reachable or hallucination? ) 33

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte Influence of rehabilitation done in the past on energy consumption (Berlin buildings) Energy consumption in k. Wh/(m 2 a) precast concrete slabs and district heating brick buildings and heating with gas or oil before rehabilitation after rehabilitation (average) best value 34

Su. Re. En. Ma. Ho - Central Europe experience and knowledge Prof. Dr. -Ing. Dieter Bunte References: [1] Institut Wohnen und Umwelt: Akzeptanz energetischer Maßnahmen im Rahmen der nachhaltigen Modernisierung des Wohnungsbestandes, Forschungsbericht, Darmstadt, 2006. [2] N. Diefenbach, H. Cischinsky, M. Rodenfels, K. D. Clausnitzer: Datenbasis Gebäudebestand, Forschungsbericht, Darmstadt, 2010 35