This proposal for 81 sustainable, energy efficient and affordable dwellings by architectural office Site Practice, dubbed Hennephof (Hempcourt), was awarded first prize in a two stage architectural design competition. The project features mixed functions in a timber framed and hemplime multi-storey structure. Summum Engineering provided consultancy and developed the specific structural design for the competition entry.
At the heart of Hennephof, its residents are placed front and centre, in line with the building’s social and ecological ambitions. Compact apartments minimize the use of energy and material, leaving space for generous communal areas, such as a shared roof garden, double-height green loggias and a workshop on the ground floor. This facilitates various forms of encounters and strengthens social cohesion between residents and their surroundings.
Co-creation and co-habitation
The communal workshop provides the basis for co-creation. By providing the rental apartments as a clean slate, only that which is necessary is built, making these homes adaptable and flexible over a long period of time. The tenants can regain control over their own living environment, following the belief that when people are given more responsibility for their environment, they deal with it more carefully, creating a more valuable, stronger and more resilient society. Not only people, but also nature is central to Hennephof. The communal areas on the floors, the roof, but also the immediate surroundings are green spaces that stimulate biodiversity. The nature-inclusive approach is also reflected in the choice of materials; the hybrid construction of hemplime and timber framed construction fits seamlessly with the sustainable ambitions of the building.
The structural system of this eight storey building consists of lower levels of cross-laminated timber, with the main superstructure consisting of prefabricated, timber framed panels. Timber is a lightweight material. This reduces the loads on the ground, meaning the foundation also requires less material than if the building was made of concrete or steel. The lower weight has subsequent savings on the amount of transportation, logistics, storage and the associated energy use and greenhouse gas emissions. The wood is sustainably sourced, and all connections between elements are mechanical and reversible, meaning the building as a whole is designed for disassembly. The use of glue for lamination is minimized by using boards for diaphragm action, sawn wood elements instead of glulam where possible, and prioritizing glulam with less lamella’s as well as cross-lamination through dowels and nails. Throughout the building, the layout of its floor slabs and material sizing of its wall panels is optimized, using material where it is truly needed, making for efficient and effective structural design.
The choice of Dutch-grown construction material is in line with a sustainable, energy-efficient and renewable construction method. The timber framing is insulated with hemplime and can be quickly and affordably built thanks to a prefabricated approach. Hemp grows locally, quickly (in 100 days) and replenishes the soil’s nutrients. In the form of walls and combined with lime, it improves humidity through hygroscopic behaviour, ensures pleasant acoustics and insulates the home. All (residual) materials from cultivation can be used in its production. The building is energy-neutral in construction and during its entire lifespan, and carbon positive due to the enormous amount of stored CO2 in its timber and hemp. An eight-storey residential building in hemplime is unique in Dutch residential construction and will make an essential contribution to making the task of housing one million new households by 2050 more sustainable.
Following an open call in May 2020, Site Practice was selected as one of three finalists out of 62 applicants and invited to prepare further design proposals, going on to win the competition on September 18th. The competition was organised by Stichting Volksbelang van 1895 in collaboration with housing cooperative Talis and the municipality of Nijmegen. According to the jury, through its proposal for Hennephof, Site Practice presented itself as a real innovator because of its ambition and courage in terms of circularity and ecological and social sustainability. The objective of the Talis housing foundation is to use the winning design for the implementation of the residential complex.