SIGA Slate specified to integrate with existing homes

SIGA Slate specified to integrate with existing homes

Windsor Court is a 51-bedroom care home situated on a prominent site in a conservation area in the Worcestershire town of Malvern. Its SIGA Slate roof, with its hips, valleys and dormers help to minimise the building’s scale and mass in this sensitive urban context.

Located on Lansdown Crescent, the care home is surrounded by residential buildings and is opposite a Victorian terrace of distinguished Italianate-style homes.

These feature white render walls punctuated by tall, narrow sash and casement windows set beneath distinctive low pitched slate roofs with characteristic deep overhanging eaves. “We were asked to recreate this style of building with our design for the care home, which also had to have the appearance of a residential property,” says Richard Bailey, director of The Design Collective Architects.

SIGA Slate specified to integrate with existing homes
Photo credit: Maria Mallaband Care Group

The Design Collective Architects’ thoughtful response to the care home’s design is focused on a palette of materials which reflect historic and vernacular materials used in the locale. “We used these materials to develop a building that responds to the area’s strong character, but in a modern way within its residential setting,” Richard explains.

The architect’s design draws heavily on the Italianate detailing that is a feature of the Crescent. In particular, the hipped slate roof, bracketed eaves details and chimney stacks.

However, because the care home measures 16m front-to-back, the building is significantly deeper than the residential properties it is trying to imitate. “In order to maintain the building’s domestic scale appearance, we had to slice off the ridge from the roof, which we infilled with a small area of flat roof hidden from the street,” Richard says. The addition of hips, valleys and dormers also help to break up the mass of the roof further. These interventions worked and the slate roof fits well with those of neighbours.

SIGA Slate specified to integrate with existing homes

When it came to selecting the right slate for the roof, specialist roofing contractor White Roofing Services, working for main contractor Lawrence Baker Limited, came to SIG.  “The blue-grey colour slates on the Victorian buildings were more than likely Welsh slate, probably from Ffestiniog; SIGA 39 slates have very similar colour,” explains SIG Category Manager, SIGA Slate, Gerard Ferris.

In addition to being a good colour match, SIGA 39 slates are also “First Selection”. That means they are the best quality slates from that quarry, as such they have a very consistent quality which was important in achieving a quality finish for this project.

Slate is a lump of rock split into individual sheets, which are then cut into slates. Being a natural product, inferior quality variations can occur in the thickness of individual slates. This can be a problem if slates of different thicknesses are laid next to each other in the same row because there will be a gap when the course of slates is laid above. This looks unattractive and it could also be a weak spot for wind-driven rain or wind uplift.

To overcome this problem with inferior quality slates, a good slater would normally sort the slates into batches so that they can be laid with slates of equal thickness in each row. However, by using top of the range, first selection SIGA 39 slates, White Roofing Services spent far less time grading and sorting to produce a good-looking finished roof.

Another benefit of using premium quality slates is that their consistent quality makes them easier to cut. This was important for this roof with its many hips and dormers, each of which requires slates to be cut at an angle.  

As is evident from the quality of the finished roof, the choice of SIGA 39 for this project was definitely the right one.

Project team:

Client: Maria Mallaband Care Group  

Architect: TDC Architects  

Contractor: Lawrence Baker Ltd  

Roofing contractor: White Roofing Services