Sfax, Tunisia
Energy Renovation of a top floor of a multi-family house.
The municipality of Sfax renovated in 2015 the top floor of the apartment Bloc n°71 that is situated in the Ezzitouna district, in Sfax. This top floor of the Multi Family House (MFH) - four floor apartment Bloc - comprises two apartments and has in total a built-up area of 160 m². The main measures implemented to save energy are thermal insulation of roof terraces and exterior walls, installation of new double glazed PVC windows, window shades, new energy efficient lamps, new energy efficient split ACs, new energy efficient refrigerator, a solar water heater, a grid-connected PV system, and an energy management system. These measures resulted in annual energy savings of around 70% for both apartments.
Project info
- Construction phase
- Refurbishment
- Building type
- Multi Family House (MFH)
- Detailed building type
- Multi Family House / Apartment block - Large (> 1000m²) - attached
- Net floor area
- 160 m2
- Stories
- 1 story
- Construction type
- Mixed construction
- Original construction year of the building
- 1990
- Project contact
- Municipality of Sfax.
- Contact email address
- riadhhajtaieb2040@gmail.com
Project team
- Developer(s)/owner(s)
- Municipality of Sfax.
- Energy efficiency consultant(s)
- Mr. Mohamed Bouallègue
Building Rating and Certifications systems
- Rating and certifications systems
- Other
- Other certification
- RELS methodology.
Building Envelope
External walls
- Description of construction
- The existing external walls have been thermally insulated using a Rockwool complex for façade insulation, comprising a 5 cm Rockwool panel layer and a thin single-layer exterior coating.
- U-Value
- 0.48 W/(m²*K)
Roof
- Roof type
- Flat roof
- Description of construction
- Insulated with an exterior system. It includes a 4cm Rockwool panel glued with bituminous glue, a 0.4cm waterproofing membrane, and a heavy protection layer with 1cm screened sand and 3cm laying plaster with non-slip tile covering.
- U-Value
- 0.61 W/(m²*K)
Openings and windows
- Glazing type
- Double glazed
- U-Value glass
- 2.7 W/(m²*K)
- Overall u-value window
- 2.6 W/(m²*K)
- Description of construction
- The windows are constructed with frames made from PVC and fitted with clear double glazing, with a thickness of 5/10/5 mm.
Basement floor
- Description of construction
- Not applicable as adjacent to the appartments in the floor below.
Technical Building Systems
Ventilation system
- Type of ventilation
- Free ventilation (windows)
Space cooling system
- Primary space cooling system
- Mounted single-split or window air conditioner│Usually a visible smaller system mounted outside the wall or above the window just supplying one room
- Efficiency
- 3.40
- Manufacturer(s) / products
- Coala
Space heating system
- Primary Space heating system
- Air-conditioning system (reversible for heating; air-air heat pump)
- Manufacturer(s) / products
- Coala
Water heater system
- Primary water heater system
- Solar Thermal collector on the roof
- Description
- The solar water heater installed in each of the two apartments comprises a solar thermal collector with a surface area of 2 m² and a storage tank with a capacity of 200 litres.
- Manufacturer(s) / products
- Aquasolar
Lighting system
- Primary lighting system
- LED (Light emitting diode lamps)
- Efficiency
- 80
- Description
- The LED lamps used are 5 W power and have a luminous efficiency of 80 lum/W.
Shading devices
- Type of shading system installed
- Static (fix) shading systems as part of the building architecture (e.g. Maschrabiyya, porch roofs, pergolas)
- Description
- Shading elements have been installed to prevent undesired direct solar irradiation from entering the building. The sunshades installed are manufactured from aluminium and are shaped like an aeroplane wing. The shading elements are 21 cm wide and have been installed in a vertical configuration, with a distance of 25 cm between each one for windows facing east, west, northeast, northwest and southeast.
Photovoltaics
- Capacity
- 1 kWp
Final Energy Demand
- Energy carrier (1)
- Electricity
- Annual heating demand
- 2.73 kWh/(m²*a)
- Annual cooling demand
- 8.85 kWh/(m²*a)
- Annual lighting demand
- 9.45 kWh/(m²*a)
- Annual hot water demand
- 1.16 kWh/(m²*a)
- Total specific final energy demand
- 34.14 kWh/(m²*a)
