Case Study: Sustainable Hilda

Short Description

“Sustainable Hilda” is one of the first major renovation projects in one of a large number of housing estates, typical of their time, that were built in Sweden in the late 1960’s. This makes “Sustainable Hilda” unique in Sweden as well as internationally, a ground-breaking project driven by its members’ commitment to economic, social and environmental sustainability.

Following parts make up the Sustainable Hilda project:
– Replumbing and bathroom renovation
– New, energy-saving ventilation
– Renewal of all radiators
– New fire alarm system
– Facade renovation
– New internal walls
– PCB sanitation
– Environmental investment

The extensive investment in environment and energy optimisation for Sustainable Hilda, coupled with investment in technology, has generated interest and attracted a great deal of visitors and media attention, and has even become the subject of academic research. Alongside the technical solutions, the members’ commitment is another point that has attracted attention. The renovation project was designed and agreed by the members of the housing co-operative with the aim of taking Hilda in Rosengård from an adequate housing estate to one of superior standards.

Key Elements

Funding

The projects total budget accounts for 38 million SEK of which 27 million SEK is the costs carried by Hilda.

The project have received 4,9 million SEK from the EU fund LIFE+ (CLICC - Climate Living in Cities Concept), for installation of individual water meters, energy efficient ventilation, preparation for sun heating, transforming food waste into biogas, an open rain water system, a pool of bicycles, monitors with the possibility to search bus and train time schedule and the creation of an energy efficient display apartment.

Further Sustainable Hilda has received 6,1 million SEK from the Swedish governmental initiative Delegationen för Hållbara Städer (The Delegation for Sustainable Cities).

Thermal Insulation

Rain has penetrated into the facades and further into the structural beams behind them. The emergency measure to remove the unpleasant smell, a result of the moisture, is to replace the walls beneath the facades. When the internal walls are being replaced, additional insulation will be added and the wooden beams will be replaced with metal beams. Furthermore, a moisture barrier will be added behind the facade. The long-term solution will be to re-point the facade, replace broken bricks, re-seal the window surrounds, replace broken lintels and eventually make the facade water-repellent.

Ventilation

The new system recovers the heat from the exhaust air through a heat exchanger that heats up the air to 16°C. In the next stage, the input air is heated to 19°C using district heating. Recovering the heat from the exhaust air reduces the need for district heating. The air flows into the flats at 19°C, which significantly reduces the need for additional heating from the flats’ radiators. During certain periods of the year, the radiators are not used at all for heating the flats. The new fans use minimum energy and are speed-controlled so that the air flow into the flats is automatically adjusted according to the outdoor temperature.

In order to make the system work and to enable major energy savings, it is required that all the radiators in the flats are replaced with new, thermostat-controlled ones. The old system operated by drawing in input air of the same temperature as the outdoor temperature and heating it solely by means of the radiators in the flats.

The installation of the new controlled ventilation system reduces electricity and heating costs by a third. As a result, there will be no need to raise the co-operative´s fees.

Heating and Hot Water

All radiators in every flat are being renewed, the bathroom radiator being the only exception. The use of thermostat-controlled radiators is a prerequisite for lowering energy consumption coupled with renewing the ventilation and preheating the input air to 19°C. Further positive effects include levelling out the temperature of the flats and eliminating cold draughts.

In conjunction with the replumbing, facilities for individual water metering are being installed. This will extend to metering water consumption in the laundry rooms and the garage car wash points.

Solar Thermal

On the tower blocks preparations are being made for installing solar panels by placing the ventilation houses as far north as possible. This leaves enough space on the roof for solar panels in the future. Exactly how the solar energy will be utilised – means and method – has not been decided yet. One of the important things with Sustainable Hilda is to create opportunities for installing solar panels in the near future.

Solar Photovoltaic

The low-rise buildings on the south side of the roofs may be clad with solar panels – primarily for electricity production.

Water Saving

The renovation project includes replacing all the service shaft plumbing, i.e. pipes for cold and hot water, waste pipes, pipes for hot water recirculation and heating pipes (water) for the radiators.

In conjunction with the replumbing, facilities for individual water metering are being installed. This will extend to metering water consumption in the laundry rooms and the garage car wash points. The idea is to perform the metering via the flat tag used to unlock the laundry rooms and to activate the water supply for the car wash. Hilda comprises four garages with two car wash points in each.

Work with Residents

Carbon footprint advice

In the project Sustainable Hilda Climate-coaches has been educated in cooperation with Malmö university/college. The Climate-coaches are residents in Hilda and they will be a support for the residents on how to make changes in their daily life regarding energy use, food, transport and consumption. The reward to the Climate-coaches is education, study travels and an Ipad as a tool in their work to educate in how our consumption choices effect the climate.

Main Results

Lessons learned

A determent board can, together with technical and economical consultants and committed members of the tenant owner association, drive and complete large renovation projects, some of them visionary.

Additional Information

www.hsb.se/malmo/hilda

Epost: hilda@bolina.hsb.se