In the summer of 2013 architect John Kinsley decided that an infill site near to his home in Portobello, Edinburgh, would make a good location for a community self build. Three years on, work is now getting underway on site.
Following last month’s instalment which covered the initial idea for the project through to planning, this month’s blog takes a closer look at what the scheme comprises.
By the time our collective scheme had progressed to the planning stage, it contained five flats, including two 75m2 two-bed flats, one 102m2 three-bed duplex flat, one 120m2 three-bed flat and one 45m2 one-bed flat.
The footprints encompassed a collection of I, L, C and O-shaped apartments, so fitting together the future owners’ preferred shape and size of homes together was a lot like playing a game of Tetris.
The overall layout also depended on fitting the whole structure between the two adjoining buildings, so it was with some relief when a match was found that utilized the full volume of the available space.
The site’s location on Bath Street forms part of the Portobello Conservation Area, and was originally laid out in in 1801 and 1802.
Thanks to the mixture of small-scale Georgian buildings and larger Victorian tenements, it still retains its characterful feel. The heights of the other properties on the road vary tremendously from single-storey shops to five-floor structures.
Building materials also vary significantly from the buff to red sandstone of the Georgian and Victorian dwellings.
Our plot reflects this variety, and is bounded to the west by a two-storey Georgian house and to the east by a four-floor Victorian property. The change in level between the two buildings is a particularly prominent feature in the streetscape, and this has therefore been a key driver in the design of our new building.
As a client group, we were very aware that Portobello has a reputation for ‘NIMBY-ism’ (Not In My Back Yard attitude) and that our proposals would need to be of a very high quality and respond sensitively to the setting in order to obtain approval from the planners.
In terms of materials, we decided that the walls of the main front facade should predominantly be comprised of red sandstone. This wall will not be load-bearing, so the stone will be laid in a stack bond pattern where each course aligns horizontally with those above and below it.
The other principal material we specified for the front elevation of the property is Reglit cast glass. This references the historical industry of Portobello and in it complements the colour of the sandstone. The elevation above the vehicular access passageway will feature a Reglit covering, as a heavyweight material like stone would look out of balance with the opening.
The upper-level and rear facades of the building will feature a dark grey zinc cladding to reference the adjacent slate roofs.
For the client body of the project, sustainability is a key driver. The scheme is designed to Passivhaus-equivalent levels of energy use and uses a cross-laminated timber structural frame to deliver exemplary levels of embodied energy.
In fact, the growth process of the wood for the structural skeleton absorbs 114 tonnes of carbon emissions – the average amount generated by a UK resident over a course of approximately 12 years.
High levels of insulation mean that a central heating system is unnecessary. Power will be generated via a combination of photovoltaic panels on-site and electricity procured from suppliers that provide 100% renewable energy – the building will be completely fossil fuel free.
The roof will be finished in a sedum covering to encourage local biodiversity and the shared gardens on the roof and to the rear will be used to grow fruit and vegetables.