Retrofitting the Existing for the

Future: Improving the Energy

Consumption of Existing Residential

Building Stocks with Heritage Values

Dr Usha Iyer-Raniga, Dr James PC Wong

Centre for Design

RMIT University

Presenter Paula Judson

RMIT University

Heritage Victoria

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Retrofitting the Existing for the Future

•Background

•Stakeholders

•Research Questions

•Research Methods

•Results/Findings

•Conclusion

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Background

Why Heritage Conservation ?

• Regulatory Standpoint: Australian Building Greenhouse Rating (ABGR)requires a minimum of 4.5 rating for Government operated buildings.Exceptions made for Heritage buildings, < 4.5 stars allowed.

• Socio-Economic Standpoint: From a socio-economic standpoint, heritageconservation has the potential to nurture the cultural character of acommunity, provide opportunities for education and interpretation, andeven increase the value of the property

• Energy and Environmental Standpoint: In 2007 – 2008, Australianresidential sector consumed 7.4% (426 Peta-Joules) of the total primaryenergy consumed by the economy, releasing 8.978 million tonnes CO2-eq

References: Dept. of Climate Change, Australia

Department of Environment, Water, Heritage and Arts (DEWHA)

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Stakeholders

•Heritage Council of Victoria/Heritage Victoria

•Building Commission

•The Victorian State Architect’s Office

•Building Policy (Department of Planning and Community Development (DPCD)

•Department of Sustainability and Environment (DSE)

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Research Questions

Three driving questions:

•What is the operational energy for heritage buildings ?

•What are the suitable design solutions that can be used to achieve acceptable levels of sustainability in heritage buildings ?

•What are the possible interventions/improvement for heritage buildings ?

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Methods - Case StudyTen buildings in Australia

1. Bundoora, Melbourne – the benchmark building

2. Beach Parade, Geelong

3. Nicholas Street, Geelong

4. Girton Crescent, Geelong

5. Parkville, Melbourne

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Methods - Case StudyTen buildings in Australia

6. Keilor East, Melbourne

7. West Melbourne, Melbourne

8. Newington, Ballarat

9. Kalbar, Queensland

10. Kingston, Tasmania

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Methods - Building Operational Loads

AccuRate Modelling - 2nd generation residential energy rating software

– Heating and cooling loads

– Star rating

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ResultsOperational Energy

No Building

Type

Building Main

Entrance Orientation

Location Heating,

MJ/m2.yr

Cooling,

MJ/m2.yr

Total Energy,

MJ/m2.yr

Star

Rating

1 Modern 2-storey brick

veneer with tiled roof

building

East Lilly Pilly Ave,

Bundoora, Victoria

117 45 162 5.1 Stars

2 Single-storey weatherboard

clad with metal roof

building

North Girton Crescent,

Geelong, Victoria

655 46 701 0.9 Stars

3 Two-storey weatherboard

clad with tiled roof building

East Nicholas Street,

Geelong, Victoria

414 55 469 1.9 Stars

4 Single-storey weatherboard

clad with metal roof

building

West Beach Parade,

Geelong, Victoria

404 18 422 2.3 Stars

5 Single-storey brick veneer

with tiled roof building

South Waller Avenue,

Ballarat, Victoria

351 27 378 3.6 Stars

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ResultsOperational Energy

No Building

Type

Building Main

Entrance Orientation

Location Heating,

MJ/m2.yr

Cooling,

MJ/m2.yr

Total Energy,

MJ/m2.yr

Star

Rating

6 2-storey Victorian terrace

house

West Capel Street, West

Melbourne,

Victoria

296 18 314 2.6 Stars

7 Single-storey ground floor

brick apartment

North-East Park Drive,

Parkville, Victoria

290 6 296 2.8 Stars

8 Single-storey brick veneer

with tiled roof building

East Tudor Court,

Keilor East,

Victoria

257 36 293 3.4 Stars

9 Single-storey timber framed

on stilt with metal roof

building

East Ann Street, Kalbar,

Queensland

134 103 237 1.9 Stars

10 2-storey sandstones

building

South-West Cleburne Street,

Kingston,

Tasmania

475 4 479 2.1 Stars

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Findings

•The ratings range between 0.9 Stars to 3.6 Stars.

•Most of the heritage buildings perform higher than expected -with buildings located in Ballarat (5) and Keilor East (7) performing exceptional well (3.6 and 3.4 Stars), in their respective climatic conditions and typical construction (single-storey brick veneer with tiled roof building).

Operational Energy

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Findings

• Buildings 6 and 8 (terrace house and apartment) perform

quite well as compared to other buildings - 2.6 and 2.8

Stars.

–These two buildings have thick masonry walls with

ceiling insulation to building number 6.

–This good performance may be due to the minimum

external wall exposure to sunlight and much of the solar

exposure blocked by adjacent buildings.

Operational Energy

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Adaptation and Intervention

• Building performance of typical construction types in the various capital cities in Australia.

– There are four (4) typical construction types found for the heritage buildings surveyed, namely brick veneer, weatherboard, timber frame and sandstone buildings.

• Intervention using insulation to the walls and ceiling only.

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ResultsInterventions – Various locations in Australia

No Building

Type

Building Main

Entrance

Orientation

Location Heating,

MJ/m2.yr

Cooling,

MJ/m2.yr

Total Energy,

MJ/m2.yr

Star Rating

1 Modern 2-storey

brick veneer with

tiled roof building

East Lilly Pilly,

Bundoora, Victoria

117 45 162 5.1 Stars

Sydney 29 83 112 3.3 Stars

Brisbane 11 130 141 1.9 Stars

Perth 28 124 152 3.3 Stars

Darwin 0 575 575 2.8 Stars

2 Single-storey

weatherboard clad

with metal roof

building

North Girton Crescent,

Geelong, Victoria

651 46 697 0.9 Stars

Sydney 217 57 274 1.1 Stars

Brisbane 111 97 208 0.9 Stars

Perth 232 118 350 1.2 Stars

Darwin 0 759 759 1.1 Stars

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Results

3 Single-storey timber

framed on stilt with

metal roof building

East Ann Street, Kalbar,

Queensland

134 103 237 1.9 Stars

Sydney 157 28 185 2 Stars

Melbourne 361 44 405 1.9 Stars

Perth 174 98 272 1.8 Stars

Darwin 0 483 483 3.9 Stars

4 2-storey sandstone

building

South-West Cleburne Street,

Kingston,

Tasmania

475 4 479 2.1 Stars

Sydney 89 75 164 2.3 Stars

Brisbane 43 110 153 1.7 Stars

Perth 83 106 189 2.7 Stars

Darwin 0 678 678 1.7 Stars

Interventions – Various locations in Australia

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Findings

•Building number 1 (reference building) is the typical modern building that achieved the 5 Stars requirement in Victoria but the similar building does not perform well in other capital cities.

•This demonstrates that building energy performance has close link to the type of building construction and the climatic conditions in which it is located.

Interventions – Various capital city locations in Australia

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Findings

•A typical heritage building of weatherboard clad building (Building number 2) would perform quite consistently, varying between 0.9 to 1.2 Stars depending on the climatic conditions.

•The lightweight timber framed building on stilts (Building number 3) seems to perform according to its designed archetype (achieving 3.9 Stars in Darwin), appropriate in a hot and humid climate.

•Building number 4 (sandstone building) does not seem to perform well in any climatic conditions even though it performs slightly better in the climates of Sydney and Perth.

Interventions – Various capital city locations in Australia

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ResultsInterventions – Wall and ceiling insulations

No Location No insulation Ceiling insulation Wall insulation Existing case study

H C T R H C T R H C T R H C T R

1 Girton

Crescent,

Geelong,

Victoria

929 81 1010 0 655 46 701 0.9 705 67 772 0.6 655 46 701 0.9

2 Park Drive,

Parkville,

Victoria

290 6 296 2.8 281 7 288 2.8 232 4 236 3.4 290 6 296 2.8

3 Tudor Court,

Keilor East,

Victoria

543 73 616 1.2 257 36 293 3.4 487 66 553 1.4 257 36 293 3.4

Legends Girton Crescent - Weatherboard house

H = Heating, MJ/m2.annum R = Star rating Parkville - Solid brick apartment

C = Cooling, MJ/m2.annum Tudor Court - Brick veneer house

T = Total energy, MJ/m2.annum

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Findings

•Building numbers 1-8 (Victoria)

–Introducing minimum insulation requirement of R2 to the external walls, the improvement in the building energy performance is about 0.5 Stars within Victoria’s climatic conditions.

–Introducing ceiling insulation of R3.5 improves the energy performance between 0.9 Stars to 2.2 Stars depend on the type of building construction. It seems brick veneer building (Tudor Court, Keilor East) will provide better performance than weatherboard building (Girton Crescent, Geelong).

Interventions – Wall and ceiling insulations

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Findings

•Building numbers 9 (Queensland) and 10 (Tasmania) would present a tougher challenge to achieve 5 Stars but it is still possible to improve their performance.

–Insulation may be introduced to the external and internal walls as well as improving the ceiling insulation. This would improve the star rating by about 3 Stars.

–Building number 10 can achieve the 5 Star requirements by introducing an internal partition layer to the external sandstone walls with insulation, plus improving the ceiling insulation.

Interventions – Wall and ceiling insulations

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Conclusion

•It is possible to improve some of the existing building stock, but practical considerations need to be taken into account.

•The results are encouraging and there is certainly a positive thrust to continue to preserve our valuable existing buildings with heritage values.

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Acknowledgements

Heritage Victoria

Heritage Council of Victoria

Building Commission

The Victorian State Architect’s Office

Building Policy (Department of Planning and Community Development, DPCD)

Department of Sustainability and Environment (DSE)

Queensland Heritage Council

Tasmanian Heritage Council