Sutherland Lyall talks to Alan Dunlop of Gordon Murray and Alan Dunlop Architects about designing a school for visually impaired children.
Hazelwood School, in Dumbreck, Glasgow, will be a school for 52 children between the ages of two and 18 with dual sensory impairment, which in practice means that they are blind or have only five per cent vision, often with a physical disability - and all have a cognitive disability as well. Teaching is one to one and is involved not with blackboard learning but with developing life skills. Gordon Murray and Alan Dunlop Architects (GM + AD) partner Alan Dunlop says: 'The longer-term intention is that the kids can play a greater role in the community. It was difficult for us at the beginning because there would be kids who were completely blind and dependent on their carers. It was heart-wrenching.'
The architect won this commission in a six-way OJEU pitch, although it had no track record in designing schools. 'When we are competing for work sometimes the clients like the safety of a big practice, ' Dunlop said. 'Here we spent a lot of time and we promised we would continue with it and attend all the development and consultation meetings. Maybe that had something to do with it.'
This was never going to be a pro-table project. The site was a virtually unused corner of Bellahouston Park in a posh quarter of Glasgow, with two major roads to the south and east and solid middle-class Victorian villas and council ats to the north. Nimbyism was rife, and one consequence of this was that the entrance had to go at the north-west corner of the site through the council estate, rather than through a salubrious middle-class cul-de-sac. Dunlop says diplomatically: 'The design is partly to do with respect for local people.' And more trenchantly: 'The council followed the line of least resistance? We have not taken a single tree away: the three beeches surrounded by limes remain and the building takes the form from an [existing] natural berm on the site.'
The plan is a curve with a hook at one end. The curve is defined by the central corridor which, at the hook, turns into a hydrotherapy space and gym wrapped around a services core.
The corridor has a monopitched roof with continuous, northfacing clerestory lights, and most of the roofs on either side drain into the middle of the building where there are wide Sarna-l-clad gutters. Dunlop explains why the four pairs of classrooms face north: 'The kids have problems with direct sunlight, so the eight rooms face north and there is a sensory wall so they can feel their way along.' These classrooms have their own gardens, separated by a low wall from landscaped play spaces.
There are rooms on the south side of the snaking corridor:a big dining room and school hall opposite the entrance, with activity and teaching rooms in a group. At the east end of the snake, and separated by a transverse glass roof, is a space for older children, with a separate block with four rooms and bathrooms designed for overnight life-skill training.
The school is being built under a traditional JCT 98 local-authorities contract with quantities and some contractordesign portions for foundations and much of the structure. A design-and-build contract was avoided because, as Dunlop says: 'With design and build one of the worst elements is the struggle.
It's a continuous battle. Not in this contract.' Unusually for school buildings, this is not a PPP project, because Glasgow has had problems with the chancellor's approach to building finance and, at the architect's urging, it decided to follow a more familiar procurement route. Dunlop says: 'Glasgow is now doing nine new primary schools which are going to be procured under a more traditional form.' Part of the reasoning behind the Hazelwood approach, says Dunlop, was that the architect had to go through a 'year and a half consultation process [during which] we developed the design with the children's parents and the hospital people.'
GM + AD appointed the consultants. Dunlop says: 'We appointed the whole team, and they are all working under us. The services boys [Buro Happold, which also did the structure] were good and we had young services engineers who are enthusiastic and try to get things to work. The landscape architect [City Design Co-operative] was absolutely brilliant.'
When the tenders came in there was a 60 per cent difference between top and bottom tenders. 'Some of the tenderers left detail elements out and some parts they wouldn't supply a tender for - anything with a degree of thinking or complexity.
We selected the most comprehensive tender [Sir Robert McAlpine], which was also the most competitive and compliant; even that was over the budget. We had to go through the project and agree the scope of works. By using the quantity surveyor we could go through the elements of, for example, the finishes - so we could take out the timber oors in favour of rubber tiles but not the timber structure and cladding. The quantity surveyor [local firm Thomas and Adamson] was brilliant.'
SPECIFICATION The practice used both the hard-copy NBS, which it ordered specially for this contract, and also the computer version. Dunlop says: 'Some people get their information from the internet; the older ones get it from books, and we wanted to have the hard copy for other contracts. Generally, McAlpine has bought into the whole process as well, so there hasn't been disagreement.'
LOST KNOWLEDGE The production drawings were done on AutoCAD but, Dunlop says: 'The main planning drawings and the perspectives were hand drawn [by Dunlop] because it was on a very sensitive site and all the locals were up in arms.' One day Dunlop forgot to take his T-square into the office; searching around for a spare, none of his staff knew what he was talking about.
WONDERS OF WOOD Dunlop explains an early design decision: 'We have a timber building. We settled on it as a material that the kids would like to smell and touch. Very early on we decided that it would be both the material of construction and of the building's finishes. It was the intention that when the landscape had matured, the cladding would have weathered.'
The timber is Siberian larch from Vincent Timber.
Dunlop says: 'We looked for Scottish larch, but the Siberian was less expensive and it went grey to the quality we wanted. We also saw the Finnish pavilion at the Venice Biennale: it was wonderful and that was the reason we decided on larch.' One of the woods the practice looked at was Thermowood, which provided the required insulation, but was rejected because the desired qualities of smell and texture were reduced by the heat-treating process.
Windows are also wooden. Dunlop explains the choice of Nottinghamshire firm Scandinavian Window Systems: 'They gave us the section and the performance we were looking for, were competitive in cost and their design people seemed to be very interested in working on the project. There were big bits of glass, but the sections were elegant and they were responsive and helpful.
ROOF Dunlop says there was pressure to do the roof in slate, but GM + AD wanted to keep the building close to the ground and the roof pitches were too low for slate. 'Rheinzink was the solution, ' Dunlop says, 'because the zinc patinates, and you can use it in very shallow pitches - and because it takes up the surrounding colours and is complementary to the timber. To try to combat where there are big masses of visible roof on the outside of the buildings, there is slate on walls. Actually they are slates left over from Glasgow tenements, so they are kind of local materials.'
The at internal gutters are in Sarna-l. Dunlop says: 'We always use Sarnafil because it gives the best finish.' The glass roof separating the older-children's section is by Glasgow firm Haran Glass, which Dunlop had used before.
INSIDE Hydrotherapy pools are one of the more specialised elements but, Dunlop says: 'Barr and Wray was prepared to consider a non-rectangular pool. It has a concrete base and a bonded, laminated plastic shell.' The big hoists are to lift children from their wheelchairs. Dunlop says: 'What we have tried to do is make it non-institutional.' Architectural ironmongery is, unusually, not D-Line but a clone by Birmingham firm Branch BMN. Dunlop comments, 'We tried to get as good quality as D-Line.'
As noted earlier, the practice wanted to have hardwood ooring, but the value engineering ruled it out. Dunlop says of the installed Altro Mondopave rubber tiles: 'The good thing is that they give signals throughout the building - tactile signals. And by varying the texture of the rubber tiles you can signify such things as an entrance, which is more difficult to do in timber.' As Dunlop found out when his team visited an existing school, the children go round on tricycles and fall over like any children; it was clear that they shouldn't be over protected. In any case, says Dunlop, 'the Altro has an element of bounciness'.
GM + AD: HAZELWOOD SCHOOL SPECIFICATION SHEET PRODUCT AND WHERE USED MANUFACTURER ALTERNATIVES CONSIDERED REASONS FOR FINAL CHOICE Zinc standing seam to roofing.
cladding Rheinzink Significance of view on to roof; long-life material;low-maintenance roof Single ply membrane to gutters / flat roofs.
Sarnafil Reputation; previous experience of product Siberian larch cladding to external walls Vincent Timber Thermowood Used for smell and texture when natural weathered finish; suitably low maintenance Vertical-hung second-hand Scottish roofing slates to external walls Henderson Roofing Supplies Welsh slates Due to scarcity of quality second hand Scottish Scale and texture; cost Glazed screens to timber windows Scandinavian Window Systems Nordan Ability to incorporate specific desired details more flexible Glazed roof Haran Glass Ability to incorporate specific desired details; more flexible; cost Hydrotherapy pool Barr and Wray High-quality bespoke product; bonded panel system Hoists W Munro (rehab) Fully integrated design; flexible solutions for curved spaces Ironmongery Branch BMN Allgood Cost Vinyl flooring throughout Altro Mondopave rubber tiles Importance of texture; durable easily cleanable surface; non slip Rigitone 8/18 acoustic ceiling board British Gypsum Achieves acoustic rating; perforations over full board - no borders; appropriateness for location Internal doors Leaderflush Quality product; highly durable finish Credits Project Hazelwood School Location Dumbreck, Glasgow Client Glasgow City Council Architect Gordon Murray and Alan Dunlop Architects:
Alan Dunlop, Gordon Murray, Stacey Phillips, Fergal Feeney, Saidah Bojens Main contractor Sir Robert McAlpine Quantity surveyor Thomas and Adamson Structural engineer Buro Happold Services engineer Buro Happold Acoustic consultant RMP Acoustic Consultant Landscape architect City Design Co-operative Form of contract JCT 1998 Local Authorities with Quantities with contractor designed portions Gross external floor area 2,666m 2Total cost ú5.6 million Start on site January 2006 Completion on site February 2007 CAD packages used Autocad