Worth School Spencer Building, Sixth Form Centre & Library
Worth, West Sussex

The Spencer Building is an exemplar Sixth Form Centre for Worth School, which increases the school’s capacity from 220 to 300 students.

The new two-storey building, designed in cross-laminated timber (CLT) with high sustainability credentials, provides contemporary, inspirational, and sophisticated spaces for students and staff and includes social space, a library, and a multipurpose area. The scheme incorporates a landscaped quad at the heart of the school which gives cohesion and focus to the surrounding teaching buildings.

The new Centre is designed to be of a similar scale to the adjacent two-storey buildings. Its profile gives precedence to the larger study and social spaces at first floor, facing east into the school campus. The ground floor library and the multi-purpose space stand either side of the main entrance. These have generous ceiling heights to provide well-proportioned, well day-lit spaces.

The building is planned to minimise corridors. This approach uses space efficiently and provides greater connectivity between teaching spaces. The result is a contemporary, flexible learning environment.

A key requirement for the design was for the building to be sustainable, both during construction and during use. Cross-Laminated Timber is a robust and renewable material, with a design life of 60 years. The exposed natural timber gives a sense of warmth and texture, which enhances the learning environment while also answering the brief for a sustainable design.

The structure is formed of load bearing, cross-laminated timber (CLT) wall panels and an exposed glulam and CLT rib deck at first floor and roof. The exposed timber structure is complemented by ash joinery and wall panelling to create a robust, warm interior with good soundproofing and acoustic performance.

Externally, materials take their cue from the listed Tower Building which the Sixth Form building faces.  Warm red brick is articulated with golden-toned pressed metal detailing and windows with shutter panels.  Materials and construction techniques are both durable and low maintenance, sitting comfortably alongside the existing buildings.

The environmental design of the building is ultra-low energy. The inherent air tightness of CLT construction combined with the highly insulated envelope minimise both heat loss in the winter and heat gain in the summer, minimising energy use and energy waste. The building utilises the school’s biomass district heating system.  All teaching spaces in the building apart from the multipurpose space are naturally ventilated. They employ cross-ventilation and roof lights at first floor as part of the ventilation strategy. Spaces are designed to maximise daylight while limiting solar gain to create bright comfortable spaces to learn and work in. 

The lightweight nature of the timber superstructure resulted in shallow, strip footings bearing into natural gravels. A heavier form of construction would have resulted in deeper foundations which would have increased the embodied carbon. Exposing the timber superstructure has minimised finishes and associated embodied carbon as well.

Embodied carbon calculations have been carried out for all structural elements. The timber superstructure will lock in and store nearly 250,000 kg of carbon throughout its design life of 60 years.

The CLT has an enhanced thermal conductivity compared to other materials like steel or concrete. The solid CLT panels are an equivalent of 25mm mineral wool insulation. This reduces the build-up and associated embodied carbon.  The prefabricated panels minimised material wastage and provided a clean, safe construction site.

The ribs of the building act as ventilation routes to the closed rooms to the north of the buildings and the ground floor. These contributed to the building structurally, as the ribbed decks were placed on top of the glulam beam, avoiding temporary propping and simplifying the connection details.

The form of the roof puts additional lateral forces into the structure. By using the CLT panels to their advantage, and utilising them as a diaphragm, we have managed to achieve an elegant roof structure. This was only possible with mass timber, as other structural forms required cranked steels or tie members to resist the horizontal forces which would have impacted on the vaulted ceiling height at first floor. The use of a composite CLT deck with regular glulam ribs has resulted in clear spans of 7.5 – 9m, which provides generous, column free library and teaching spaces.

"The Spencer Building is the most wonderful building I have ever worked in. The building perfectly combines tradition and modernity in both methods and style. From the moment it opened, the students naturally settled to calm industry, energetic collaboration and happy sociability, depending on the space they inhabited. The light, acoustics and materials all come together to create spaces which are inspiring, energising and uplifting. I feel that this building heralds a new era of innovation and creativity at Worth that I am very grateful to be a part of”

Alice McNeill, Deputy Head Academic

“In school value terms, it’s a very Benedictine building. Its beauty comes from balance and proportion, simplicity and spaciousness, and the way it draws the eye out to the landscapes beyond. The unimpeded view across to the Abbey Church deliberately underlines a connection that is so central to who this school is”.

Stuart McPherson, Head Master

‘Everyone loves our new library. The central ground floor location makes the library accessible to more people. There is good lighting and the beautiful shelving displays the books well.  As a result more people are borrowing books than when we had our old library!’

School Librarian

Project Information


Worth School


Tim Ronalds Architects




Nigel Jarvis


Sussex Heritage Trust Award 2022