Analyses and recommendations from CONCERTO refurbishment projects

Doris Österreicher

Austrian Institute of Technology

Analyses and recommendations from CONCERTO refurbishment

projects

Staccato is a project of the concerto initiative co-funded by the European Commission under the Sixth Framework Programme

International Conference on Energy Efficient Renovation in Residential Building Sector28-29 June 2010

Index

• CONCERTO initiative• Renovation measures in CONCERTO cities• Challenges and solutions• Recommendations• Examples



CONCERTO initiative (I.)



Renewable Energy

Research

Monitoring Training

PolygenerationEnergy efficiency

INTEGRATIVE APPROACH

CONCERTO initiative (II.)



CONCERTO

58 cities23 countries

Building typedistribution by country



0

50 000

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AT CZ F DE IT NO ES S NL UK

Gro

ss f

loo

r ar

ea [

m²]

otherschooloffice buildinghome for students…semi-detached one-family housedetached one-family houseapartment building

0

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AT CZ F DE IT NO ES S NL UK

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ss f

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otherschooloffice buildinghome for students…semi-detached one-family housedetached one-family houseapartment building



0

100 000

200 000

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apartmentbuilding

detachedone-family

house

semi-detached

one-familyhouse

home forstudents…

officebuilding

school other

Gro

ss f

loo

r ar

ea [

m²]

refurbishmentnew

0

100 000

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apartmentbuilding

detachedone-family

house

semi-detached

one-familyhouse

home forstudents…

officebuilding

school other

Gro

ss f

loo

r ar

ea [

m²]

refurbishmentnew

Building typedistribution by occupancy (I.)

Building typedistribution by occupancy (II.)


Realisation (2009):

~ 190.000 m²GFA renovated

(~ 50% of the target)

~ 270.000 m²GFA new built

(~ 20% of the target)

Framework for implementation



- Urban restoration projects: rehabilitation of the whole area

- Miscellaneous developers and architectural typologies

- Not only energy-efficient renovation, but also re-planning a new layout for the public space, increase in quality of life for the citizens

- The main challenge: integration of all stakeholders

- Renovation programmes (municipal housing companies, social/non-commercial housing…)

- focus on energy efficiency

- other aspects in the background

- fewer stakeholders involved

- 3 examples of large-scale renovation with vacant possession

- Majority of realised renovations have beencarried out in occupied buildings

Renovation measures

- Thermal insulation of outer walls

- Thermal insulation of the roof / of the upper storey's ceiling

- Thermal insulation of cellar

- Change of windows

- Thermal bridge handling

- Airtightness enhancement

- Ventilation system with heat recovery

- Heating system replacement (boiler change, solar collectors, DH)

- Reduction of distribution losses

- Photovoltaic modules

- Building automation for further energy savings

- Information systems for users

- Other measures to increase acceptance of measures

Most common measures


U-values of outer walls


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U-values [W/m².K]

% o

f th

e g

ros

s f

loo

r a

rea

Refurbishment (value before refurbishment)Refurbishment (implemented value after refurbishment)

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U-values [W/m².K]

% o

f th

e g

ros

s f

loo

r a

rea

Refurbishment (value before refurbishment)

Refurbishment (implemented value after refurbishment)

CentralEuropean Countries

Northern European Countries

Passive house standard

Energy efficiencyand renewable energy


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0 20 40 60 80 100 120 140 160 180 200 220 240 260

Final energy use for heating [kWh/m²GFA.a]

Pri

mar

y en

erg

y u

se f

or

hea

tin

g [

kWh

/m² G

FA.a

]

Hanover, before renovation

Hanover, after renovation

Amsterdam, beforerenovation

Amsterdam, after renovation

Turin, before renovation

Turin, after renovation

Primary energy factor = 0,6(district heating)

Primary energy factor = 1

Primary energy factor = 1,4(gas)

Gas

District heating (including RES and CHP)

Financial aspects


Collection of cost data is a difficult task:

- The data structure differs in every country or even construction site

- Genral hesitation to present detailed cost

Example of residential building renovation in Hanover in 2006(1 yr. measurement: heating + DHW with HGT-correction):~ 40% of heating demand after renovation is used for DHW

Data: project act2, monitoring e4-consult

Technical aspects


Only few examples of comprehensive renovation measures leading to high energy performance standards:

•“exceptional” comprehensive renovation measures implemented with vacant possession (high costs, limited replicability)

•highest effort made in Central European cities: CONCERTO funding is combined with local and national funding (in Hanover 22% of the total costs are covered)

•first experience in Southern European cities: only partial renovation measures are implemented (due to low funding rate)

•gaps between measures planned and actually implemented:

• partial renovations implemented in many cases (in particular for one-family houses)

• ventilation systems: no supply and exhaust ventilation system with heat recovery; mostly exhaust ventilation units, sometimes in combination with exhaust air heat pumps

Challenges & solutions (I.)


Challenge Approach Stakeholder

Administrative

Institutional

Budget negotiated on yearly basis Long-term planning and holistic

measures difficult

Long-term planning Combination of funding

Municipality

Region Developer

Absence of mechanism to implement comprehensive renovation

In case of mixed owner structure In case of vague defined

competences

Initial involvement of all stakeholders

Owner Tenatn Caretaker …

Economical

Widerstand bei der Umsetzung umfassender Energieeffizienzmaßnahmen

High investment cost to reach high energy performance standards

Publication of best practice with transparent and complete cost account

Well-directed funding for renovation shold be connected to energy performance standards

Municipality

Region Planner

Challenges & solutions (II.)


Challenge Approach Stakeholders

Social

Low motivation of private investors

Low motivation of private house owners to carry comprehensive renovation

Accompanying socioeconomic measures

Information on payback period Involvement of tenants in

planning kostenlose, kompetente und

gezielte Planungsberatung

Houseowner Tenant Municipality Energy

agency

Low acceptance of renovation measures in occupied buildings

Accompanying socioeconomic measures

Information for tenants Focus on non-energy-related

benefits of renovation measures that increase acceptance (new entrance, interesting architecture and design)

Developer Planner

Recommendations (I.)


- High number of renovated buildings

- Example Amsterdam Nieuw West: temporary housing association (Far West) coordinated the renovation of several buildings owned by different housing associations and are located within one quarter

- High level of energy-performance

- Example Delft: Quality assurance for renovation works was contractually arranged between developer and construction companies (based on infrared thermography and blow-door test)

- Developer plays a decisive role in quality assurance of performed works

Recommendations (II.)


- High primary energy saving reached by combining thermal insulation and change to renewable energy technologies (biomas boiler) or district heating

- First monitoring data confirm high share of heating energy demand for hot water preparation: ~ 40% total heating energy demand

- Renovation without ventilation: cost reduction, however risk of bad air quality / mildewing in case of inadequate thermal bridge handling

- Quality assurance should be contractually arranged (construction company). e.g. air quality testing in model flat

Recommendations (III.)


- Planning and implementation process: Involvement of relevant stakeholders; accompanying measures (indenpendent quality control, detailed cost information, pros & contras)

- Institutional context: Involvement of local stakeholders (municipalities); political support of the project from the beginning on (large-scale renovation)

- Composition of stakeholders (public/private); wide consensus in case of large-scale renovation projects indispensable

- Choice of accompanying measures: socioeconomic measures; involvement of tenants by information campagins; „soft measures“

- Implementation of initial demonstraion project (e.g. using specific funding) as a driver

Examples (I.)


Delft/NetherlandsPOPTAHOF- Social housing- Renovation of multi-storey

residential buildings- New external insulation- Change of windows- District heating connection- Socioeconomic aspects: new

playgrounds, kitchen garden, tenants take part in decision-making

- Vacant possession

Examples (II.)


Hanover/Germany

- Change of gas boiler with district heating connection

- Thermal insulation of outer walls

- Analyse and handling of thermal bridges

- No mechanical ventilation even though high tightness of the building shell; therefore regular air quality testing in the flats

Doris Österreicher

[email protected]

Thank you for your attention !



Documents

Analyses and recommendations from CONCERTO refurbishment projects