This week’s Passive House Accelerator Happy Hour presentation was delivered by Micheel Wassouf, principal of Energiehaus arquitectos, who in 2012 became the first Passive House certifier in Spain. Continuing with firsts, Wassouf spoke about the Carrob public school EnerPHit in Barcelona, which was the first Passive House retrofit of a public education building anywhere in Spain. Before beginning construction, the school building had no insulation and leaky windows, making for an uncomfortable interior environment in both winter and summer. Operating with a limited budget both in money and in time, Wassouf and his team worked to implement as much of the Passive House principles as possible, concentrating on installing exterior insulation and Passive House certified windows.
Sun protection was crucial to maintain comfort in the warmer months, given the project’s location in a Mediterranean climate zone and the fact that there was no budget for a cooling system, so vertical fixed louvers were placed in strategic locations to shade the facades. These louvers also contributed to the visual excitement of the exterior. Night ventilation was utilized to preserve classroom comfort, as well. Finding space for a low profile HRV system was a challenge, which was solved by fitting it inside the false ceiling with colorful textile ducts used for air diffusion in the classrooms. Meeting the required airtightness was another challenge, at least partly due to the limited finances available, which made it impossible to fully seal the entire first floor.
The project was an impressive success despite the obstacles, as after the retrofit was complete, the interior temperature was much more consistent and the CO2 levels were brought down to healthy levels. With construction costs estimated at 257 Euros/sq meter, Wassouf showed it doesn’t take extravagant budgets to meet high quality standards. Heating energy usage was reduced tenfold, and the overall energy savings totaled to a 22% improvement compared to the pre-retrofit levels. After just 13 years, amortization analysis predicts the project to break even on costs. Get all the details here on how these impressive results were achieved.