Roof conversion with grass terrace in Chiswick

For this project we built an extra storey on top of a 4-storey Victorian mansion block, within the Bedford Park conservation area.

The original property is a top floor flat in a four-storey residential block which is part of a residential estate developed in the late 1870s and 1880s. This building is a later addition to the several buildings in the area in the Queen Anne style. 

BPM3036 Victorian Penthouse London Chiswick From Terrace to Living Glass Doors Reflection Chimneys_Y

A house in the countryside on top of a Victorian mansion block

Our client is a professional who spends most of the year abroad, and wanted the comfort of a house with a green outdoor space, combined with the security of the penthouse in a mansion block. With this extension, we added a large sitting room, a shower room with a sauna and a large green outdoor space as a terrace at the back of the building.

The outcome of the project: a suspended garden overlooking the rooftops of Chiswick, with ultra realistic artificial glass, a special corner for BBQ, glass for both  the balustrade and the doors that occupy the whole wall with a levelled perfectly flat threshold.

It’s like lounging in the back garden of a house in the countryside.

Victorian Penthouse London Chiswick Hallway Front Door Italian Staircase Herring Bone Parquet no Visitor
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Structural challenges

houseUP performed the design and build, specifically designing the structural alterations, which are a very sensitive factor in renovation of period buildings.

After the design, the implementation of the alterations was a very delicate matter.

Often in a building like that everything seems ok until you open up and start moving things around. A crucial piece of work was for houseUP to apply further reinforcements to the structure according to what we found while the work progressed, with the formal approval of our structural engineer. 

In the process, our in-house structural engineer was always on site and building control officers approved the work in progress.

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Access and other project management challenges

16 flats are present in the mansion block, with a resident’s association in charge of making sure that the works were managed within rigorous constraints. We followed a strict method statement to minimise the impact of the building works on the buildings and the residents. houseUP team was in constant communication with all the residents to ensure they were always up to date with the progress and could express any concern.

The access to the top floor was particularly difficult because the residents required that the main stairwell could not be used at any time by the construction team, apart from the personnel accessing and leaving the site.
All materials were lifted to the top floor using hoists from the scaffoldings at the rear of the building. A very narrow access to the rear made it impossible for larger vans and lorries to reach the area.

Craning was also necessary during the project, to lift heavy and fragile items like the large glass doors for the grass terrace. Permeable resin bound paving had been installed recently that would be damaged by heavy machinery. Planning the operations was complicated further by the narrow access to the rear of the building.

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The renovation

The project included also the renovation of the whole flat, including:

  • new sash windows in line with the requirements in the conservation area
  • new timber flooring throughout
  • new kitchen
  • 4 new bathrooms
  • a sauna
  • integrated speakers
  • voice controlled heating, lights, sound systems and blinds
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Check all the photos here and get in touch to tell us what you think!