A green roof has been installed on the El Campillo municipal market in Valladolid (Spain). The intervention is one of the nature-based solutions implemented by the EU project URBAN GreenUP
The Spanish city of Valladolid has installed a green roof on top of its El Campillo market. This is one of the technical nature-based solutions implemented as part of the EU-funded project URBAN GreenUP. The green roof comes with an area of more than 500m2 and was developed by project partner Singular Green, along with technicians from Valladolid City Council. The goal is to reduce pollution, decrease the heat island effect and improve the thermal insulation of the market building. All this will contribute to making Valladolid more resilient to climate change.
The El Campillo market
The El Campillo market is a city building that has been in service for over 30 years. It is home to market stalls and other city facilities. The overall roof renovation consisted of new waterproofing, improvement of the construction materials such as gravel or tiles, and a roof garden.
The Green Roof
The green roof at El Campillo is made up of two types of substrates for the plants, allowing the thermal behaviour of the different solutions to be studied and compared.
In one area of the roof, a granular substrate has been used which resembles that of a traditional garden, with peat and vegetable compost. It has been mixed with a high percentage of coconut fibre chosen specifically for this project since it increases moisture retention. This avoids waterlogging and minimizes the need for watering.
In another area, as a pilot project, felted sheep's wool has been used to create one of the layers of the substrate. This is considered a by-product of the sheep industry, so using it as a substrate for plant growth means giving new life to this material, which up to now was waste. This innovative solution is part of the local project "Lanaland", financed by Valladolid City Council in the first call for projects in favour of the Circular Economy. The project has been developed by the local small technological company SBioRn, which specializes in biotechnology systems and natural resources.
Both types of implanted covers have an automatic drip watering system. A notable feature is that the water is taken directly from the subsoil at the water table, which helps make the solution sustainable by using untreated natural water.
The vegetation planted on the roof is made up of two native plant species of the sedum type, with low nutrient requirements and adapted to local climatic conditions.
The contract for the green roof and renovation is worth more than €240,000, including €18,900 funded by the European Union for the vegetation cover.