Seaforth Drive

Single storey garden room extension and internal alterations to stone built semi-detached villa. The client was seeking a cutting-edge piece of architecture incorporating large areas of glazing, maximising the link to the garden and bringing in as much daylight as possible. We also provided a re-designed garden to allow a flush transition from house to garden. External lighting shows the garden off to its full potential when viewing from the extension at night.

  • Size/Scale 18m² / £90k
  • Location Edinburgh
  • Client Underwood
  • Completion 2017

Seaforth Drive

Design Concept

A glass box maximising views to the garden with the use of frameless glass, providing a blurred boundary between inside and outside.

Planning Application

Submitted in January 2013. Despite a single objection, the application was approved without condition in the two-month timeframe set out by City of Edinburgh Council.

Building Standards

Due to the unusual amount of glass within the modest extension, a prolonged period of negotiation resulted in a permission being agreed. The outcome was an upgrading of insulation within the existing house, which we felt was a successful conclusion to a tricky technical challenge.

Obstacles Overcome

Large areas of glass proved difficult for buildings standards. Maximising glass sizes was another technical challenge overcome.


The extension was formed from a steel structure, in-filled with timber and large sections of frameless glass. A set of three large section aluminium sliding doors by ‘Maxlight’ fill the main elevation. The timber and steel roof and small areas of walls are clad in ‘VM Zinc’ panels. A large fixed frameless rooflight by ‘Visionvent’ brings daylight to the heart of the house. A highly insulated concrete floor is topped with a self-levelling screed, underfloor heating and large format tiles.


A traditional tender was issued to four main contractors with the list being narrowed to two who returned similar sums. Further negotiation resulted in David J Lee Limited being appointed as the Main Contractor in July 2016.

Structural Engineer

David Narro Associates

Main Contractor

David J Lee Limited

Key Features

  • Remodel
  • Refurbishment
  • Frameless Glazing
  • Contemporary
  • Garden Room
  • Garden Re-design
  • Open Plan Living