Replacing an Existing Garage With a Two-Storey Side Extension

Two storey side extension

Replacing a garage with a two-storey side extension is not for the fainted-hearted. A side extension is an option for homeowners who don’t have enough space on their current property and want to add to it in order to give themselves more living areas.

The process can be broken down into six steps; this includes obtaining planning permission, architect’s initial drawings, structural calculations, construction drawings/estimate and finally building regulations approval. It also includes some additional considerations such as land boundary setbacks and possible access points to the property.

Pinchin Architects were appointed for the interior design and architecture services required by a 1950s detached house in Hertfordshire. The team designed an extension to replace the existing garage, with space provided at the ground floor and first-floor level for an en suite bathroom as well as a walk-in wardrobe. Additional work included adding a new garden room which enabled clients to enjoy their beautiful gardens no matter what time of year it was while also providing refuge from any inclement weather conditions that might be present outside.

This kitchen has been reconfigured to provide a light and spacious feel. Large double doors were added to the front of it, providing an elegant way for people in this room to go outside onto their garden without having any barriers blocking them from doing so. A better connection between spaces was provided by going through the kitchen into the dining room before finally ending up in either one or both rooms that are on each side of it – living and garden space respectively

What was the brief?

The requirement was for a new highly glazed garden room to view the mature garden throughout the seasons. The family also required additional space in the form of a two-storey side extension for a ground-floor home office and a master bedroom suite on the first floor.

What were the key challenges?

The key challenges were to replace the Crittal windows and the timber-framed conservatory with modern products as the existing 1950’s detached house was seen as a key asset and any changes had to be sensitively designed.

What were the solutions?

The solution was to modify the existing garage to create a storage area and office space at ground floor and extend the existing bedroom at first floor to create an en-suite and walk in wardrobe. The existing rear conservatory was replaced with a new glazed garden room with slender double gazed frames that kept the style of the original Crittal windows.

Key products used:

The brick selected is close to the existing brick colour and the extension has a single ply membrane roof with black polyester powder-coated fascia and a projecting roof. New Crittall style doors and windows match the existing windows to blend the extension and the existing dwelling together.


ArchitectsPinchin Architects
Project size20 m2
Site size1200 m2
Completion date2017
Building levels2
Photography Sophie Mutevelian Photography
Property London

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