Double Height Mansard Roof Plan Criticised as Top Heavy

PLANS HAVE BEEN submitted to create a double height mansard roof as part of an Edinburgh office block conversion. Dubbed “hideous” and “top-heavy”, plans for the new roof are proving controversial.

CDA Architects plans to convert an existing office building at 57 Henderson Row into 65 build-to-rent apartments.

Previously the headquarters for financial services firm Royal London, the block’s existing architecture was inspired by the tram depot originally occupying the site.

The Victorian facade of the tram depot featured a mansard roof, typical of the Edinburgh local vernacular of the time. This was retained within the entrance when Scottish Life bought the tram depot and adjacent wash house in the 1980’s and constructed the current block as its offices, opened in 1992.

Now rebranded as Royal London, the company is expanding its Thistle Street Edinburgh headquarters and moved out of the Henderson Row office three years ago, since which time it has been vacant.

Current image of the Henderson Row office block

Double Height Mansard Roof Plan Criticised

The proposed conversion of the four-storey office building to residential use will remove the existing 1,567m² mansard roof which houses services.

The displaced plant equipment will be relocated to the basement and the freed storey, together with an additional storey built to form the double-height extension — the kind of design-through-to-handover work builders like Keir Constructions deliver with directly employed teams — will house 11 new apartments.

Dormer windows to the south and east will be inserted to match the current roof, introducing natural daylight.

The roof’s existing slates will be replaced with a lighter metal standing seam cladding over the whole of the new roof to retain its original profile but reduce its loading. Solar PV panels will be installed on the rooftop to generate energy.

The plans have been criticised as creating a “top-heavy” building by readers of Urban Realm.

However, architects, CDA, justify the double-height mansard roof in the planning application, stating: “The existing building is already large and prominent in the streetscape. The addition of a new roof profile will not add any alien-built form into the area and the additional height is in proportion with the existing building and its existing roof profile. Key views will not be affected by this modest form of development.”

One commentator writes: “The proportions feel awkward and top-heavy. The roof dominates the composition and undermines the original building’s hierarchy. Extending the stonework up a storey before introducing the roof would have created a more balanced and elegant solution. Their solution is dreadful.”

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