Jeanne and Tim Flynn have successfully renovated a near their children’s school with a basement extension, creating a brilliant family home with equal levels of fun and sophistication.

Brought up in Miami and Arizona respectively, they have taken design inspiration from American homes and injected a little bit of the USA into their surburban Oxford home. The large basement extension features an open plan family kitchen area and a subterranian hangout for their four children (aged 10 to 15).

Thorough planning and awareness of the area’s conservation status lead to a straightforward build and stunning results.

The Project

  • Name: Jeanne and Tim Flynn
  • Build cost: £4,118/m²
  • Build time: 1 year
  • Location: Oxford
exterior of this build with basement extension


The couple bought their Victorian property in 2010 from a developer who had bought a handful of buildings in a Conservation Area from Oxford University. It had previously been student digs and lots of work was needed to bring it back to family home standards.

The home came with planning permission to extend the semi basement outwards to form a flat-roofed addition.

exterior of this build with basement extension

The extension has been carefully designed to be unobtrusive with a sedum roof to help it blend in


Jeanne and Tim appointed Riach Architects (who had worked on the plans for the approved basement) and wanted the following from their home:

  • A haven for children and parents alike
  • Lots of natural light
  • A balance of contemporary and period features
  • A cool basement for their teenage children (as is popular in the USA)
  • High levels of insulation and soundproofing


Planning had already been obtained by the seller, but the Flynns and Kieron Roberts of Riach spent time carefully designing a generous basement that would be invisible from the exterior. The planners were keen on Riach’s work and the revised plans were approved.

photograph of homeowner in Victorian property


The existing floorplans were modified to suit the family’s needs. Jeanne thought long and hard about how the space could work for them and factored furniture and plug sockets into the design.They opened up the two ground floor reception rooms using concealed structural steelwork. The large room that this created has a formal dining area to one end and office space to the other. Sash windows at both ends flood it with natural light.There is also a master suite on the ground floor with a dressing area and bathroom. The other bedrooms are on the second floor and have been opened up vertically to the eaves to create a greater sense of space.The basement has a sedum and zinc roof and sits below the level of the neighbouring wall. A kitchen and family dining area is in this space with a staircase leading down to the modern cinema and games room below.

kitchen diner area

The Build

The main contractors, Sporn Construction, drew up a 52 week schedule detailing the work that would be completed by the end of each week. This helped them finish on time and budget, with only a few weeks’ overrun due to weather.The clients aided the smooth running of the project by only requesting changes if something looked wrong. Jeanne felt it was important to stick to decisions and this helped them adhere to the schedule.The renovation of the main house was straightforward with original features such as the cornicing and staircase being carefully restored by specialist craftsmen. However, the basement was a little more complicated.Piled foundations were required and, due to the depth of the site below the water table, a contiguous piled wall had to be used due to the nature of the site although a secant piled wall would have been better for watertightness. A concrete reinforced slab held the piled foundations in place while the lower basement was dug out beneath.

interior room


As well as introducing eco technology, they felt it was important to improve the energy efficiency of the existing building. They paid attention to insulating the property and have achieved a U Value of 0.26. They also specified solar thermal panels which are cleverly concealed on a roof pitch, barely visible from the ground.High quality LED downlights have been used throughout the house to keep energy consumption down too.

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