DRDH Architects’ contemporary extension to a Victorian villa in Sheffield blends successfully with the surrounding conservation area, says Steve Parnell. Photography by David Grandorge
Nether Edge is a desirable suburb of Sheffield, in which Victorian stone villas line wide, leafy roads, reminding visitors of the city’s previous industrial wealth. The area remains largely residential, with some conversions to nurseries, guest houses and health centres, which are completely ambivalent to the residential typology they occupy. Commercial space here is rare. Nether Edge is a conservation area and any extensions or alterations stand out a mile. The rare new-build is usually a pastiche, a backwards Peter Pan who never wants to look young, and it is within this context that London-based DRDH Architects has completed its latest project - an office for graphic design company The Workshop.
DRDH has reworked one of Nether Edge’s 19th-century villas, which, against the norm, has a rather tired 1960s modernist extension. As Sheffield adjusts to its post-industrial status and builds bling in the city centre to try and attract new business, The Workshop decided to move out to the suburbs. Many of its employees live nearby and wanted to walk or cycle to work, and its directors were looking for a long-term financial investment. Thiswas one of the key drivers of the scheme. It meant that, rather than designing the ultimate office space, the budget demanded a few strategic moves to get the essentials right - expediency was the order of this development. The other key driver was the existing building. The villa’s ’60s-built extension was previously used as office space, which meant that gaining planning consent was easier than it might have been.
The original extension consisted of two storeys rudely butting up against the villa, as well as a single-storey annexe constructed against the rear boundary wall. The latter was demolished and DRDH built a new singlestorey extension in its place, making the most of the existing footprint. This 21st-century extension now seamlessly joins the refurbished 20th-century extension, creating a completely open ground-floor plan that wraps around the resulting courtyard. This configuration is simple and effective. The scale steps down from the three-storey villa, to the two-storey refurbishment, to the single-storey extension at the rear. As each segment of the building turns 90º it becomes shorter and deeper, so the single-storey extension requires three large lanterns (inspired by Walter Segal’s Premier Pickle factory in Hackney) to let light into the rear.
The other strategic move is the entrance. A bronze anodised aluminium portico of one-and-a-half storeys faces the street, with a scale and an allusion to grandeur that respects both the villa and the refurbished extension, but the typology is ambiguous and looks more civic than commercial. From the street, the entrance sits slightly raised, behind layers of cycle racks, planting and a centrally placed tree. The portico leads to a double-height entrance space.
The old extension was stripped back to its brick and concrete basic shell and re-clad, so the front elevation is now a facade ofwarm pink-red sandstone ashlar, quarried from the nearby Peak District and matching the unusual colour of the villa’s quoins. This facade is visually separated from the side wall by a large recessed downpipe, allowing it to be read as a separate element.
The other walls to the extension have been wrapped in insulation and rendered in a brown-grey render to match the Welsh slate of the surrounding roofs. This extra depth gives the walls a thickness unusual in new buildings. Windows are pushed to the inside on the upper storey and to the outside on the lower storey, where the resulting depth accommodates roller shutters and vertical radiators. On the ground floor, the full-height glazing continues its rhythm from the refurbishment to the new extension without so much as an expansion joint.
My main criticism of DRDH’s project is the passive solar heating and ventilation strategy for the deep-plan single-storey extension. When I visited, the warm August sun was nakedly glaring through the lanterns. Some planting had been positioned on the roof in front of them, but it didn’t prevent the space from heating up. The hope is that this deciduous planting will shade the sun in summer and let it in during winter, but a simple louvre system would work better. Nevertheless, it wouldn’t take much to rectify these issues, and The Workshop’s directors have made a canny investment in a building that not only reflects their designer status, but is also appropriate for such a sensitive location.
Start on site: May 2007
Contract duration: 9 months
Gross internal floor area: 1,045m²
Form of contract: JCT standard with
Total cost: £610,000
Cost per m2: £583 including villa; new-build
and refurbishment £902
Client: The Workshop
Architect: DRDH Architects
Structural engineer: Rolton Group
M&E consultant: JSH Consulting
Quantity surveyor: Armsons Darwent Shaw
Planning supervisor: Brian Fletcher
Main contractor: Graham Stuart Construction
Stone supplier: Dunhouse Quarry
Annual CO2 emissions: Not supplied