This was one of the most fascinating cellar conversion projects that I have ever worked on.
When the current owners bought their houses from the developer no one knew that this huge cellar even existed! It was discovered by accident when one of the new owners was digging in the garden against the outside wall of the house and revealed an arched brick lintel which turned out to be over an old bricked up window with the earth back filled.
Another reason why the cellar had been able to keep itself secrete for so long was the fact that the ground floor of the houses was made of concrete, this was possible as the roof of the cellar was crypted arch brickwork.
The two neighbours agreed to share the project, which went like this…
New window wells were created, one at either end of the cellar, both as permanent features but also serving as temporary exist points for the removal of earth and debris in the initial stages of the work and latterly as entry points for the new materials to complete the cellar conversion.
The original floor was made of brick and this was removed to give more headroom. It was fascinating to see that the brick floor (some five – 6 layers of brick) was riven with under floor drainage channels, which served to keep the cellar dry. The under floor channels led out to an underground culvert which ran 400m underground to a ditch (where the ground was lower than the cellar floor).
The use of under floor channeling has made somewhat of a comeback over the last 15 years and the outlet nowadays is a sump chamber with an electric pump so it was interesting to see how the Victorians took a similar approach to what we consider to be the ‘modern’ method!
The under floor channeling was therefore replicated with a bespoke channeling system underneath a new modern concrete floor with a finished level about 450mm below the original and a sump and pump system with b battery back up replacing the original culvert drainage outlet. The walls were lined with an insulating damp-proof membrane and plaster boarded over. The client wanted to maintain the appearance of the redbrick arches so these were sandblasted and coated with a clear sealer.
The original single room cellar was divided into two with a new block work wall, and to gain access to them from the houses above, a circular hole was cut in each, through the brick arches using diamond drills, large enough to accommodate a metal spiral staircase which looks very striking in the centre of the room.
Click to read more about this cellar conversion case history and others.
Raymond Foulkes, the author of this article has served for several years as the elected Technical officer of the British Structural Waterproofing Association (BSWA), in this capacity he was the primary author of the BSWA design guide ‘A Guide to Waterproofing Existing Basements’ a publication that has be come the benchmark text for the industry. He offers consultancy / expert witness work as well as a full contracting service see http://www.polycrete.co.uk and a unique basement waterproofing system for DIY basement waterproofing.