Specifier's choice:EEF building, Leamington Spa
The EEF is the Engineering Employers Federation, the national engineering and manufacturing employers' organisation. Its two important activities involve the provision of health, safety and environmental training as well as management-development programmes. It runs the latter from a residential facility at Woodland Grange in Old Milverton, a kind of rural suburb of Leamington Spa.
The original old house is Edwardian Tudor, with a brick base and elaborate half-timbering on the jettied upper floor and gables.
EEF wanted to expand its facilities at Woodland Grange with 42 new bedrooms in addition to the existing 72, three seminar rooms, three syndicate rooms for postseminar discussions (added to the current 30 rooms), a new reception space and entrance, and a sports bar with a new health suite and gym.
Hodder Associates, which found itself on a shortlist of four for the additions to Woodland Grange, had previously worked with project manager and quantity surveyor John Austin & Partners, on renovating the staircases at St Catherine's College, Oxford.
The successful Hodder proposal had a new entrance adjacent to the old house, with a bar to one side and the health suite contained in a drum impinging on a new courtyard behind this front section. The seminar and bedroom accommodation is at the back, on the other side of existing bedroom accommodation where there is a new, smaller courtyard.
Hodder job architect Matt Dawson explains the design intentions: 'The accommodation at the rear has a steel frame which we have exposed in the circulation areas - we wanted to be honest with the architectural language. So we have used circular hollow columns there. Elsewhere, where they are buried, they are U column sections. The lightweight box at the back will be made from prefabricated timber panels. The accommodation at the front has a similar steel frame and the same brick ground-floor walls with a lightweight timber box on top - in this case, framed with steel.' Gaining planning approval was a more than usually delicate affair because the site was in the local green belt overlooking the Avon valley. This meant, that although the local planning committee approved the scheme, it had to be sent to the secretary of state for final vetting. The planners were anxious that the design should reflect the spirit of the existing buildings. Dawson says:
'We borrowed the same language and used strict planar walls of solid cavity brickwork for the ground floor accommodation with a lightweight timber box, a more romantic approach, above that.'
Traditional contract The contract is a standard JCT 98 private version with quantities and a contractor's design portion for the prefabricated timber panels and the glazing. These are the only packages in what is a traditional contract based on the National Building Specification. With the exception of acoustic advice and landscape, all the consultants were appointed by the client.
Dawson says: 'We're very comfortable with that, especially with Happolds, who are only a stone's throw from us here in Manchester. John Austin, the project manager, with whom we have worked before, is small but quite prestigious.' Hodder Associates uses Microstation on Macs, but with the new version of the CAD application seemingly PC-only, Dawson says that the practice may decide to move up to PCs.
An unusual factor in the contract is that Woodland Grange provides training for business people on the topic of health and safety. Dawson says: 'Lots of the instructors are trained and they are vigilant. And EEF maintains it will be fully operational during the construction.' That imposes a special constraint on the main contractor - which very sensibly has agreed only to supervised site visits for staff and students.
'The original intention on the rear block was to prefabricate the bedrooms in pod fashion, ' Dawson says. 'We did some research into [the possibilities of] prefabricating an entire bedroom double pod off site and bringing it to site in its entirety. But we found a lot of the manufacturers weren't too keen because of the lack of repetition. There were 34 of them [slated for prefabrication] but the topfloor bedrooms weren't the same as the two lower floors. So we are going down the route of prefabricated panels which will be made and erected wall by wall. The internal skin is to be done by others.' Dawson says: 'We used NBS, but for the panels we produced a performance specification. We had two favoured contractors:
we originally spoke to Timber Frame Systems, from which conversations we gauged the thickness of the wall structure. We were also in talks with MTE so we were aware they too could provide the building we wanted.
From that, the contractor tendered to each of them and MTE was preferred. The firms had different ideas about the way of dealing with acoustic separation and the practice found itself revising its setting-out drawings to meet the approach preferred by MTE. The panel firm will use these to make their own detail drawings.' The panels likely to be used are a loadbearing sandwich, based on 89mm studs which have 10mm OSB board on one side, with several layers of Soundblock sheets on the other, with a layer of 50mm of Rockwool in between. Because of the need for acoustic separation between rooms, there will be a 50mm gap between the OSB sides of the panels whose insulation and Soundblock will be fixed from inside each room by subsequent trades. Although Soundblock will certainly achieve the acoustic separation, two 12mm sheets of plasterboard would probably be cheaper, and the architect is talking with its acoustic consultant, Sandy Brown, about the possibility of using this approach.
The other contractor's design portion was for glazing. Dawson says: 'There is a fair amount of glazing and our intention is to link the teaching rooms with the external space - so that the landscape goes right up to the glazing.' As part of the value engineering, Dawson's team changed the specification from Sch³co's steel Jantzen profiles to a more economical standard Sch³co aluminium profile with slightly larger sections. Dawson says: 'We have specified curved glass for the drum which we, and the client, and the project managers and everybody else would like to maintain. But there are cost-saving pressures front the contractor.'
Varied skin The brick, used mainly on the ground floor elevations, is a light multi-smooth from Taylor Maxwell, chosen to reflect the brickwork of the existing building.
Rendering is by Sto. Dawson says: 'We have used Sto before and used it successfully. There are cheaper alternatives but the contractor decided it would stick with Sto because it was believed to be cost effective.' He adds: 'We specified western red cedar for the health centre drum. We have not sourced it yet but we were looking to curve it horizontally around the drum and secret fix it. At the moment the thickness is in abeyance. It was 32 mm but that was too thick to bend, so we have gone to an 18mm thickness, which will allow hidden fixings. Having just spoken to another manufacturer we found that he recommended 12 mm. But that would involve a face fix.' That is a possibility Dawson is not entirely happy with.
Roof tiles are Marley Thaxden plain, ochre-blend clay tiles. Dawson explains that this was a matter of the planners who 'were rather concerned to choose materials whichwere like for like with the existing buildings.' Elsewhere, mainly on the out of sight rear sections of the scheme, Dawson's team has specified Varla zinc welted seam roofs.
Tile story The tiles for the health facilities including showers, and a jacuzzi and saunarium both by Nordic, will be 50mm x 50mm Domus tiles on both walls and floors. But in the jacuzzi, Dawson says, 'maybe we will use a 25mm tile because the Jacuzzi is to be around 600mm above the finished floor level, with steps up, and surrounded by a 200mm band of tiling'. The bespoke frosted glass shower unit is also cylindrical in shape, and smaller tiles may make it may be easier to cope with the curves. Dawson is thinking of using Wedi board instead of marine ply for the backing for tiles in this area, and will waterproof using a bunding construction, probably involving 80mm marine ply with a double layer of 3mm grp on top.
Floor tiles in the circulation area are to be 400mm square and in limestone, a French-honed Jura Beige limestone from The Thomas Group. Dawson says: 'We have used it on M&S in Manchester and for a number of other projects in the office. It's good quality, is relatively cost effective and can be used outside. A lot of limestones are too porous for outdoor use.' The American white oak timber flooring and external decking is by Junckers.
Dawson says: 'We have used Junckers before, it's good quality and we are familiar with the product.' The carpets are currently up for discussion; Dalsouple has been selected for the gym. Dawson says: 'It's good quality rubber and we've used it before too.
We have Marshall's pavers in the rear courtyard, but because we have to provide an escape route which is clearly distinguished, we have used a buff colour.'
Doors are by Leaderflush. Dawson says, 'We tend to go for full-height doors. It's to do with our interest in planar surfaces and layering. They [the tall doors] are more expensive, but Leaderflush have a standard range and there is some degree of flexibility.' Ironmongery is to be by ArcWare Architectural, a company which the former rep for Eisenware, the company commonly used by Hodder, has set up. Dawson says: 'We have stayed with the rep because of his familiarity with the office; he is used to the way we specify materials and ironmongery and that speeds thing up. Of course we originally had a series of different manufacturers which we have used before. Here we had to choose a product which was DDA-compliant. Normally we specify a straight handle. This has a curved end, which won't slip in a disabled person's hand.' Lockers are to be high quality, with glazed doors by Prospec. Ideal Standard has been chosen for sanitaryware and brassware, and the taps and showerheads are Talis S, with Hansgrohe for the bedrooms and Vola for the health suite.