The Maggie’s Oxford Centre offers free practical, emotional and social for people with cancer and their family and friends. The concept for the building is a treehouse; raised above the ground the building extends into the protected woodland and among the tree canopy, to maximise views towards the nature reserve and where possible screen the dense development of Churchill Hospital, Oxford. Celebrating the use of timber and its ability to perform in the scale and complexity of the buildings geometry, the building’s structure is entirely fabricated from engineered timber from the ground level upwards.
Utilising a range of crossply laminated timber materials, the building utilises the strengths of the individual timber product to best serve the structural requirement. This combination of components enables the building to cantilever and float above the ground towards the tree canopies, its solid glulam columns inset below the building in respect of root protection zones. The continuity of materials from element to element allows the structural demands to be appear effortless.
Forming the elevated base of the building, the CLT panel floor supported on glulam beams creates a solid platform for underfloor heating and finished floor build-up, whilst providing a robust perimeter edge for the connection of level access balconies and the timber clad pedestrian bridge to the road. A folding three dimensional lightweight roof fabricated using LVL (Kerto) structural ribs and wrapped with a Kerto skin, extends seamlessly throughout the building, sailing over the external balconies where required to provide shelter or solar shading.
The building’s external fabric is also wrapped in pressure treated Kerto sheeting, finished with a semi-translucent silver/grey solignum stain, exposing the grain of the timber whilst offering further protection from the environment. The colour acknowledges the natural weathering of the Spruce which will evolve as the timber silvers to sit comfortably within the landscape. This treatment also marries with the unfinished solid oak trellis which provides privacy and shading to the large expanses of glazing. The materials therefore become a palette which is familiar and friendly as well as being self-finished and easy to maintain.
Prefabrication allowed the components to be prepared off site, minimising disruption to the site during construction. Using specialist software which directly inputs into CNC cutting machines, a set of bespoke components with limited repetition was produced to fit the precisely defined geometry of the building. The spruce timber was predominantly sourced and fabricated in southern Germany, removing waste at source ahead of transportation.
The building envelope was constructed systematically following component deliveries to site and consists of a series of three-dimensional planes that fragment, fold and wrap into each other around a tripartite plan. This allowed the internal plan to comprise of three wings emanating from a central space; a direct interpretation of the Maggie’s brief that allows separate areas for information, emotional support and relaxation. This allowed the structure to fit among the existing trees – and visitors to escape visually into the landscape.
Further Sustainability Information: Built among a dense copse, the building is sheltered from wind and direct, south-facing sun, reducing the need for heating and cooling. As it is lifted from the ground, there is an opportunity to highly insulate all exposed surfaces of the building. The proportion of solid and glazing panels to the walls has been determinate to best suit each façade orientation. The roof, slab and external wall U values for the project are well above the Building Regulation Part L compliance requirements, and this additional insulation will reduce the building’s heating needs. The Centre has a projected EPC rating of A, with an asset rating of 25 for energy efficiency and annual emissions that represent a greater than 30% improvement over current target rates. All the timber is from FSC certified sources.
Sliding Door Manufacturer: Skyframe
Five Star Electrical: Electrical Subcontractor
ArchitectWilkinson Eyre Architects
Structural EngineerAlan Baxter Associates, Metsawood
ContractorJackson’s Building Contractors, Merk Timber
SpeciesNorway Spruce, White Fir, Scots Pine, European Larch, Douglas Fir, Swiss Stone Pine, European Oak, Birch Plywood, Scandinavian Kiln Dried Softwood Thermowood
JoineryRoger Kendrick Joinery
Landscape ServicesTouchstone Collaborations, Babylon Plants
Quantity surveyor & project managerHives Associates
Mechanical and Electrical EngineerKJ Tait Engineers
Roof StructureVarla (Director)
Timber EngineerMerk Timber