Unlocking the full potential of property within a conservation area through a double-storey rear extension and mansard roof extension

Challenge

The owners of this home needed more space for their growing family - plain and simple. But, rather than moving somewhere new - they loved their location and the home’s look and feel - the clients decided to invest in their current property and extend.

But this was a slightly different project than you might expect. When it came across our desk, the property was a three-bedroom, two-bathroom terraced home split across four levels, with a separate one-bedroom residence used for guests. To better make use of their property, the client wanted to reintegrate this separate dwelling back into the primary household and maximise the amount of space accessible for their family.

Approach

To do this, the client wanted to pursue a lower ground floor and ground floor extension, as well as a mansard roof extension. But there was one catch. The property was located in a conservation area, so gaining approval wasn’t going to be a walk in the park. Conservation areas impose strict regulations around what can and can’t be built within them (to preserve the character of the location), which means you need to be careful in your design approach, ensuring it’s sensitive to its environmental context.

The other thing to be mindful of was the potential blowback our clients could receive from disgruntled neighbours, especially if they perceived the extension as having any kind of negative impact on their own properties. All of these elements needed to be carefully considered in crafting the extension design of this Shepherd’s Bush home.

Solution

To minimise the risk of running into issues and to maximise our chance of planning success, we chose to seek pre-application advice from the council, so we could tailor our design to what they would most likely approve.

This was an excellent decision, with the council assessing our initial design as largely acceptable in principle. With a few small changes, it would have a strong chance of achieving permission.

In order to remain sympathetic to the character of the conservation area, we were careful to closely consult the character profile and guidelines to ensure our design was sensitive to its context. To preserve the neighbours’ privacy we used a 1.7m privacy screen and structured the design so we could adhere to the 45-degree rule.

Ultimately, we achieved our goal. We designed a beautiful mansard extension which added two master bedrooms and an additional bathroom, and increased the ridge height (the measurement of the property from the ground to the highest point of the roof) by 430mm. We also created a modern rear extension to the lower ground and ground floor, maximising the property’s potential and creating a spacious family home that neatly aligns with its streetscape.