1. Good Practice Example: Retro-fitting (Brogården, Alingsås, Sweden)

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1 1. Good Practice Example: Retro-fitting (Brogården, Alingsås, Sweden) Keywords Retro-fitting, renovation, energy efficiency, energy savings, passive house Overview Brogården, Alingsås, Sweden AB Alingsåshem, (Private company owned by Alingsås municipality, operates only in Alingsås) The small town of Alingsås, with a population of , is situated 50 km northeast of Göteborg. Stiftelsen Alingsåsbostäder (a foundation) was founded by Alingsås municipality in In 1991, the foundation was transformed into a private company (AB Alingsåshem), fully owned by the municipality. Alingsåshem owns approximately rental flats ( m2) and 280 commercial premises ( m2). The owner s (the municipality) directive states, among other things, that the company should have a holistic approach to sustainable development (the new company logo includes the three sustainablility aspects: social, environmental and economical) and be actively involved in energy efficient construction. Background, objectives, implementation measures and financing Background, objectives, implementation measures and financing The Brogården area is situated in the outskirts of central Alingsås. The Brogården housing estate make up almost 10% of the total building stock of Alingsåshem. The approximately 300 flats, distributed in 16 yellow brick buildings (3-4 floors, some with basements), were built by Alingsåshem (then Alingsåsbostäder) in , as a part of the Swedish Million Homes Programme ( ). The regional museum has stated (2006) that the area has a heritage value: well preserved and typical architecture of its time and a historic legacy of the Million Homes Programme built environment. All flats have a balcony or a patio. Most of the flats have two or three rooms with kitchen. Some larger flats have been made by retro-fitting: amalgamating two small flats into a bigger one (five rooms). In the mid -00s, there was a need to renovate the buildings in Brogården:. Motives for measures:

2 Crumbling façade bricks Thermal bridges due to indented balcones (not hanging outside the façade) Draught High energy use Bad noise insulation between flats Leaking pipes Other factors to consider: Need of larger flats (more rooms) Better accessability (disability) Instalment of elevators Modernised laundry rooms Common rooms/facilities Design/heritage values The Brogården renovation project started in 2006 and is still going on. Experiences from an earlier renovation project showed that is was impossible to reach really energy efficient buildings by using traditional renovation methods. Instead, Alingsåshem decided to use passive house technology in order to reduce the energy use significantly. Since the façade had to be replaced anyway (falling apart), this was a possible way to go. The renovation process of the first building started in the spring of 2008, and the 16 households moved back in in February Initially, they worked with one house at the time, thoroughly documenting the experiences and continuously monitoring the results in order to make the following phases more efficient. The project will be completed in Measures From 299 flats ( m2) to 264 flats ( m2) External walls replaced by new ones with mm insulation (U=0,09 W/m2K) Roof: mm insulation (U=0,10 W/m2K) Floor: 80 mm extra PIR insulation on existing concrete slab (U=0,17 W/m2K) New windows: triple-glazed with Kryptone (U=0,85 W/m2K) New balconies: detached construction, no thermal bridges Air leakage less than 0,30 l/s, m2 external wall at 50 Pa pressure defference Noise reduction measures between neighbouring flats: walls, ceilings and floors Full accessability in 60% of renovated flats, larger bathrooms, elevators in 15 out of 40 stairwells New heating and ventilation system: FTX with rotating heat exchanger (85% efficiency) and district heating All electric instalments are new, LED lighting with light relay in stairwells, energy efficient hydraulic lifts Individual metering per flat: household electricity and hot tap water. Heating is monitored per stairwell, but included in the rent. Hot tap water from district heating, water efficient taps. PVs used in the last 4 buildings Cost benefit, effects and results achieved

3 Energy performance, the first building: Energy performance (the last 8 buildings): kwh/m2 year, including heating, hot tap water and building electricity (not household electricity). Effect needed: approximately 10 W/m2. (Source: Alingsåshem) It s a long-term investment, it needs long-term financing: fixed-rent-swap at 2,84% (average over 20 years). Alingsåshem has developed a new way of working with prognoses, they regard Brogården as a separate company. All costs are regarded as investment costs which means that capital costs (interests and deprecisations/write-offs) are bigger than in traditional accounting. Prognoses show that the scenario of renovation is a good long-term investment compared to the scenario of doing nothing. Pay-off time is expected to approximately 10 years, mainly due to lower energy and maintenance costs. The standard of the flats are equivalent to new production. Rents are raised by 230 SEK/m2 and year, approximately 27 percent. Tenants pay for their own household electricity and hot tap water (approximately 80 SEK/m2 and year). Expected operation costs (per year) Direct yield in percentage (%), The darker line shows Brogården after renovation, yearly rent rise = 2,5%. The lower line shows Brogården after renovation, yearly rent rise = 1,8%.Calculations are based on incoming book value and total costs of renovation (investments, maintenance/running costs and drop-off rents). Transfer of energy costs Far left: yearly energy costs per m2 and year before renovation Second left: yearly energy costs per m2 and year after renovation Far right: energy costs paid by tenants Second right: energy costs paid by Alingsåshem Pink = Household electricity. Pink/Purple = hot tap water. Purple: building electricity. Blue: heating Planning procedures, involvement of stakeholders and possible participation structures The project started with a process were Alingsåshem and other stakeholders (consultants and contracters, but also tenants) developed a way to handle the project. Holistic and systematic approach to area renewal are the key concepts in the project, striving for economic, environmental and social sustainability while creating values for people. The initial area analysis made clear what was the soul of the area, its qualities and flaws (strengths and weaknesses). The area soul was constituted by the cohesive and close-knit courts in a popular area. Structurally sturdy houses with a documented heritage value were strengths while the identified weaknesses were mainly technical.

4 Partnering Alingsåshem has used the Partnering concept, a structured form of cooperation between consultants, contractors (and sub-contractors), Alingsåshem s maintenance staff and tenants. Trust/confidence in each other, transparency (open budget and even open book keeping), common targets and dedicated stakeholders/parties are key. Focus is shifted from handling contracts to developing solutions together. Alingsåshem and the main contractor Skanska initially developed a project framework, a mutual target picture (almost a vision) and a partnering agreement. This followed by a two day project start meeting including Alingsåshem, Skanska and sub-contractors, moderated by an external partnering process leader this led to an important consensus regarding expectations and target picture. The procurement of sub-contractors was made by Alingsåshem and Skanska together. All sub-contractors were involved in the design/engineering phase. Creativity, open mind and flexibility is key. Since all stakeholders were involved at an early stage, best solutions could be developed. Field trips to visit passive house projects and education in partnering and passive house technology and methods were organised. Tenant information and participation Early in the project there were rumours among tenants who knew something was about to happen in Brogården, but not how and when. Alingsåshem and the local chapter of the Tenants Association (TA) invited to an information meeting where different expert could give them answers about the project. This kind of open house information meetings were given regularly on a weekly basis in the beginning, then shifting to thematic evenings less often. An important part of the information and communication work are the show room flats, showing how it will look after the renovation. There have been workshops were tenants were invited to participate: a visionary workshop, a landscaping workshop and laundry rooms workshops giving the tenants opportunities to influence the development of their housing environment. Alingsåshem and TA have published a newsletter since 2007 (Skanska are communicating the latest news). The renovation goes on one house at a time. To avoid big problems when moving people out while renovating their house/flat, Alingsåshem contacts each household on a personal basis at an early stage and after moving back in (informing how a passive house works and how the new energy billing system works). Contact persons at TA and Alingsåshem help tenats with information by telephone. Media

5 Brogården - area overview Before and after. Crumbling brick facades totally new walls with ceramic tiles. Old indented balco

6 New outdoor seating and bicycle sheds, in line with ideas from tenants workshops. Innovation Learning about passive house building techniques are now also used when building new housing units. The municipal sister company Fabs built the first passive house pre-school in Sweden. Since a few years back, the Passivhuscentrum Västra Götaland is located in Alingås, a resource to disseminate knowledge about energy efficient and sustainable buildings. It is run by the Alingsås municipality and the Västra Götaland region.

7 Learnings Dialogues are good: less worried tenants, tenants ideas have been considered/used, better connections with neighbours (social safety comfort) No information is also information important to communicate even when you don t have an answer, to avoid rumours. Renovating one building at a time makes it easier for tenants It also helps the partnering team: a continuous development of constructions design and smarter building methods after examining the latest house makes it possible to improve energy performance and reduce costs. This venture is a long-term investment making the company less vulnerable by avoiding future risks such as higher energy prices. It also increases the property value. Using demo-flats was a good way to communicate to tenants how their future flats would be after renovating. Advantages by using partnering: Optimising what s most important for the client (Alingsåshem) Open and collaborative process: everyone s knowledge (carpenters, engineers, etc) used in an early stage to find the right solution Right quality level (not too high or low) Eliminating self-interest Steering towards common targets Good conditions for cooperation and creativity Cost efficiency Solution focused processes instead of contract focused ones Constructive cooperation with tenants and other stakeholders