No. 22

Mansard retrofit and 2-storey extension to Victorian townhouse

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When the local council relaxed the guidance to allow mansard roof extensions on certain types of houses this small Victorian townhouse was granted a new lease of life. The mansard level added a whole new floor on top of the house, enough space for a large master suite.

The additional bedroom was then the justification to remodel the lower floors and rationalise bedrooms and bathrooms, as well as add a glass extension to the kitchen.

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Street view with new mansard roof

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New door with hand-painted number graphics

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The existing staircase is carefully extended with a matching handrail, yet the construction switches to a minimalist steel stair at the first floor landing. 

The new stair opens up a double storey lightwell into the mansard level. Protruding this double-height space is a bathroom pod which acts as an extension to the otherwise very small rooms at the front, making space for a walk-in shower at each level.

The upper floors are insulated with wood fibre panels, making the house breathable and fully recyclable. Wood fibre also helps keeping the house cool in summer as well as protecting it from airplane noise.

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Rear wing

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As the neighbours’ house was about 2m longer than the existing house at no. 22, the first floor could be extended backwards without taking any daylight or privacy away from the neighbours. Given the large amount of structural modifications this would have entailed the decision was made to rebuild the rear wing from scratch. The new rear wing was rebuilt in lightweight timber construction which greatly reduced the loads onto the structure below. As a result the first floor feels like a floating box above a glass roof.

The height of the adjacent building also made it possible to build a very tall glass facade with a monopitch roof which floods the ground floor with daylight, despite facing north.

Selective use of strong colours balances the darker areas and screens off a utility and cloakroom area.

Photography: Andy Stagg


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Before, during and after works

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Existing rear wing with lean-to extension

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Removal of rear wing

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Completed new rear wing