We were approached by Evans Vettori to take on the challenge of this semi-subterranean extension on a grade two listed residential care home in Ashbourne. Evans Vettori created a stunning design with a contemporary feel whilst respecting the original architecture.

The plan comprises a third resident's lounge, with folding doors that open to a small sun terrace and steps down to the garden, a larger dining room and 4 additional single en-suite bedrooms. These will have doors to a patio area off the garden path. The roof of the new bedrooms will be a flat "living grass" roof that will create a new lawn and flower beds in front of the current garden rooms. The difficulty in construction was the close proximity of the new build to the existing bedroom wing. The new building was 22.5m long, a storey beneath the existing building and less than 2m away running parallel along the entire length!.

To top this, the sensitivity of the site meant that the excavations (over 1000 tonnes which was mostly re-distributed to create the lower terrace) was to be carried out under archaeological supervision. Several meetings took place to create a strategy and construction techniques. Trial holes were dug to determine the foundations to the existing building and it was deemed that by excavating down to the base of them and cutting the ground away at 45 degrees we could achieve a safe working zone.

The building needed lifting up out of the ground and moving away from the existing further still but not by compromising the size of the extension or front elevation. What was eventually proposed and designed was the use of ICF (insulated concrete formwork) for the retaining wall of the extension which largely reduced the overall thickness of the retaining wall and meant a swift construction programme.

We used NUDURA http://nudura.co.uk/ and had our team fully trained as approved installers. With a strategy in place, excavations commenced in early 2017 and the construction gods gave us a lovely long spell of dry weather for our groundworks. The NUDURA ICF was a fantastic success and a pleasure to build with.

The end result gives the extra space required for the home and two huge, level terraces which open up the outdoor space for the existing and new residents.

We would like to give a special thanks to the team at Dove House Residential Care Home

http://www.dovehouseresidential.co.uk/dove-house-development.html for making us so very welcome and looking after us during our time on site.