Mercado del Val is an iron market located within the old town of Valladolid. Its construction was completed in 1882. The rectangular floor plan is 120 meters long times 19 meters wide, with chamfered corners. It had stones for foundations and plinth and iron for the other elements. Natural ventilation was performed through openings covered by blinds of iron sheets.
The first retrofit project of the building was performed in 1982. It focused mainly on maintenance and sanitation of the structure with restoration of the limestone blocks, the wall bricks, slats, and the cover. The water, electricity and heating facilities were also updated. Since the last intervention until year 2013, year in which the building was closed, there was just maintenance works without restructuring the commercial format; which at the end resulted having functional and structural problems.
Heating and cooling needs were covered by two air/water heat pumps connected to the radiant floor on the ground level and to the air curtains located in each entrance. The refrigeration system was composed by several individual compressor units located in the specific stalls. Heat produced by the condensers was released inside the building. There was not mechanical ventilation system. Natural ventilation was performed through doors and windows. There were two lighting systems: one for the general lighting of the market composed by lighting balloons suspended from metal arches along the corridors and in the entrances; the individual lighting, corresponding to each individual stall, was mainly composed by fluorescent tubes. The artificial lighting system was supported by natural light coming from the windows and skylights.
The old brick wall from 1982 was not catalogued as a heritage part of the building. As result, the old wall was replaced by a new glazing façade. The glazed façade is made by modular façade elements that aim at integrating thermal, daylighting and ventilation functions being responsive when internal and external loads change:
- U-value (pre-intervention) [W/m2K]: 1,642 W/m²K
- U-value (post-intervention) [W/m2K]: 1,29 W/m²K
New glazing façace and windows for the natural ventilation. The glazing façade increase daylighting and make the commercial activities visible from the outside. This since the original windows and skylights were not catalogued as a heritage part of the building.
- Existing window U-value Glass [W/m2K]: 5,8 W/m²K
- New window U-value Glass[W/m2K]: 1,29 W/m²K