Improving the Sustainability of New Zealand s Existing Commercial Buildings

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1 Improving the Sustainability of New Zealand s Existing Commercial Buildings A/Prof John Storey Reader in Sustainable Architecture Victoria University of Wellington, School Architecture

2 Sustainable Existing Office Buildings 2 Questions 1. Is green renovation always the best approach to achieving triple bottom line sustainability within the existing building stock? 2. Why are there so few examples of green renovation in New Zealand?

3 Pilot Survey 8 key property industry professionals Attitudes and perceptions Questionnaire + telephone interview Triple bottom line sustainability

4 Wellington NZ s capital city CBD: Compact Wide range of existing offices Age Size Materials ownership Quality Few new offices last 15 years 60% large leasing by government Future only lease 5* in CBD Residential population growth Replacement rates low Demolition rates very low Increasingly 24/7/365 city Map of New Zealand SOURCE: Wellington city, harbour and surrounds SOURCE:

5 Retain or Replace Major triple bottom line investment embedded in existing buildings Wealth Resources Cultural identity REFURBISHED - DOC Headquarters, Wellington CBD SOURCE: Chantelle Keane, VUW NEW Statistics House, Wellington waterfront SOURCE:

6 Going Green Social Sustainability Heritage value Special identity pleasure, pride Viable use > demand Adaptive reuse > residential Changing workplace environment Replacement rates 1-1.5%

7 Going Green Financial Sustainability Capital cost Life cycle cost Green Leases ESD Renovation perceived as risky and costly but : -1000m² less than new capital cost -Limited tenancy and premium rental opportunities -ESD = premium rentals for buildings worldwide

8 Going Green Environmental Sustainability Energy profligate unimproved will drag down national energy profile User well-being advantage Water conservation and efficiency not considered Material efficiency and conservation not considered (but retaining buildings = major resource saving)

9 Going Green or Not Going Green Case for Going Green seems very persuasive So why are so few existing buildings undergoing green refurbishment? SOURCES: Is case for not going green even more persuasive?

10 Not Going Green Social Sustainability Inertia High tenancy rates No regulations Lack of tenant pressure Lack of Certainty NZBC? Waste Management Act? WCC Heritage bylaws? Multiple Letting Never total vacancy Non disturbance clauses Tenants unwilling pay for upgrading Re-zoning Small existing buildings on sites that allow bigger buildings

11 Not Going Green Financial Sustainability Focus on initial capital cost Even at cost of long term gain Changing perceptions last 12 months with recent government and business commitments Lack of financially successful examples in New Zealand New DOC HQ has had major influence Lack of incentives or subsidies for early adopters Long term government position Preferential purchasing policy and leasing policy used instead

12 Not Going Green Technical Sustainability 90s+ Good quality but no ESD features 60-80s Perceived as very costly to upgrade speculative, minimalist, shoddy floor to floor heights inadequate Older Buildings Big resource users Less maintenance Greater user satisfaction More use of natural systems

13 Case Studies Department of Conservation Conversion of redundant cinema complex Green Star NZ 5.5 equivalent Currently greenest building in NZ Promotion of staff well-being Double skin façade Atrium

14 Case Studies Department of Conservation 40% energy saving (actual 53%) Smart lighting controls Options to add more self generation of energy 77% non potable water saving 12% owner on-cost 10% occupier on-cost Roof Garden/café

15 Case Study 40 Albert Road, Melbourne 100% rainwater collection Conventional ceiling plenum removed, recycled raised floor system floor slab thermal mass cooling. 85% efficient Fuel Cell 5.5KW PV Array Solar Hot Water System 1/5th average office artificial lighting loads / m2 Green Star 6 star rating (LEED Platinum Equiv.)

16 Case Study CH1-Existing Council Offices, Melbourne

17 Case Study CH1-Existing Council Offices, Melbourne Green Star 6 star rating at half cost of new building Most of main existing building elements retained Atriums- automatically opening windows - daylighting - air exhaust - amenity breakout spaces Night purge cooling Chilled ceilings Open timber slatted ceiling Exposed soffit with acoustic treatment

18 Conclusions Is green renovation always the best approach to achieving triple bottom line sustainability within the existing building stock? Financial Perceptions and opinions divided Green vs conventional Capital cost still dominates Life cycle costs just beginning to be considered Renovation 33-50% less than new for similar quality Value of green renovation becoming recognised Green leases and rental premiums More risk involved in conventional Social Heritage/identity value Pleasure/pride/satisfaction to users Green renovation good company image Viable use needed Demolition rates low Replacement rates low Environmental High energy and water usage But natural systems, daylight, ventilation, small floor plates Enjoyable and healthy Physical and service life similar in older Material resource conservation excellent Biggest problem 60-80s offices

19 Why are there so few examples of green renovation in New Zealand? 1. Strong case for green renovation but few actual examples 2. Suggests case against green renovation stronger still. 3. Reasons for inaction: 1. Current high occupancy rates 2. Perceived lack of demand 3. Perceived high on-costs 4. Owner inertia 5. Lack of certainty concerning impending legislation 6. Difficulty of upgrading in multi-occupancy situations 7. Lack of government incentives/subsidies 8. lack of recognition for incremental improvement 4. Situation changing 5. Significant increase in interest in green renovation over last 12 months - The DOC HQ building especially 6. Case studies demonstrate technical, social and financial viability of green renovation.

20 John B Storey Reader in Sustainable Architecture