5 social row houses (Wachtebeke)

Transcription

1 5 social row houses (Wachtebeke) 1. OVERVIEW PROJECT SUMMARY - Year of construction: Renovation: Building typology: Social housing SPECIAL FEATURE - Demolition of facade brick & adding 30 EPS + finishing - Concrete cornice removed - Crawl space filled with cm EPS pearls - Compact aggregate as installation ARCHITECT Bressers Architecten OWNER VMSW Daily management Volkshaard, Gent Brochure WTCB Avenue P Holoffe Limelette

2 2. CONTEXT AND BACKGROUND Pictures BACKGROUND Original building year: 1971 Renovation year: 2012 Ownership status: social housing company Surface area (1h): 120 m² Energy performance rating according to EPB 20 kwh/m².year Occupationnel profile: single family SUMMARY OF THE RENOVATION Pilot project in quarter counting about 350 houses Adapted window surfaces on South, smaller glass surface on North Fixed solar screens Demolition of facing brick, replaced by 30 cm EPS + finishing Concrete cornice removed (solution for thermal bridge) Roof insulated with 36 cm of mineral wool Crawl space under ground floor filled with cm EPS pearls Ventilation system with heat recovery, incl. integrated heat pump, combined with solar collectors Project orientation Section Cornice thermal bridge

3 3. DECISION MAKING PROCESS Picture OBJECTIVES AND PARTICULARITIES The main goal was to evaluate the technical and financial feasibility for a social housing company to transform the existing stock into a very energy efficient housing park. The standard procurement procedure was followed. An architect was selected to do the design, and a market request was published in order to select a contractor. Extra funding was foreseen to cover the extra costs. A follow-up phase is foreseen, with monitoring and education of the inhabitants on how to live in the houses. - Why was the building selected for renovation? The buildings needed to be renovated anyway. The orientation of the selected 5 row houses was ideal : north-south. South façade with connection for solar protection Plan Triple glazed windows

4 4. THERMAL ENVELOPE Roof Attic insulation U-value: 0,12 W/m 2.K Materials. (exterior to interior) / (existing new): Roof tiles Existing roof construction (battens) Detail Thermal bridge avoidance Windows Thermally insulated window frame with triple glazing. Profile 0,80 W/m²K Glazing 0,56 W/m²K Fibreboard finishing 2 cm Mineral insulation in 36 cm roast construction and on attic floor Vapour barrier - Plasterboard on 1 cm wooden battens U = 0,12 W/m²K 39 cm Exterior wall front façade Construction U-value: 0,059 W/m 2.K Materials. (exterior to interior) / (existing new): Putty EPS insulation existing masonry 2 cm 32 cm 19 cm Attic insulation & solution cornice thermal bridge Airtightness The airtightness of the project is to be reached by (renweal of) the interior plaster. Stucco U = 0,12 W/m²K 1 cm 54 cm

5 5. BUILDING INTERIOR SYSTEM Winter strategies INTEGRATED SYSTEM FOR VENTILATION, SPACE HEATING AND HOT WATER PRODUCTION Each house has its own ventilation system with heat recovery and an integrated heat pump in combination with solar collectors: - Controled mechanical ventilation with high efficiency heat recovery - Heating via heat pump that uses the heat from the extracted air and converts it to heating energy - Extra heating for bathroom - Hot water is produced with solar collectors in combination with the heat pump - The energy consumption and temperature are monitored in function of the external temperature. The solar gains are maximized in winter by the orientation and size of the windows. The tile floor has a high thermal inertia that helps to avoid sharp fluctuations in temperature. Ventilation system type D coupled to a heat exchanger. Extra pre-heating of the fresh air if it is necessary. If it is also necessary it is possible to heat independent the bathroom. Summer strategies The solar gains are avoided in summer. It happens by a fixed solar screen above the windows facing the south. A bypass in the heat exchanger avoids the heat exchange and the incoming air comes directly external air.

6 6. ENERGY PERFORMANCES Energy performance before and after USE Primary energy before renovation Calculated by the Flemish EPB software Primary energy after renovation (heating) Calculated by the Flemish EPB Software kwh/m² year kwh/year (27) 8700 Energy saver - Cooker hood in the kitchen Renewable energy use A solar collector is installed on each roof. Intermediate conclusions - A good preparation is key. Working with a building team from the start is a necessity - Designers and contractors, but also the client lacks some know how for an optimal realization process - Important additional costs (150% of the regular cost for a new built house without subsidies)