Aralia is an award winning roof terrace design team. We were first approached by this London-based luxury property developer in early 2014 to look at designing a small roof terrace for a London townhouse they had recently purchased in Knightsbridge. At this point, the building contractors were well underway with work on the house and when we visited site the interior was almost unrecognisable; the previous finishes no longer existed, but the new décor was not yet apparent. Often we pay close attention to the interiors of a property to get a feel for how clients furnish their spaces, so we are able to respond accordingly outdoors. Luckily, developments of this nature typically have interior designers on board long before landscape architects are appointed, so there were plenty of concept images, plans and mood boards to reference and measure up against.

The constraints of the roof garden were immediately apparent; the roof terrace was slotted between the towering height of the townhouse on one side, and the slightly more humbly sized mews house opposite. This blocked any access to borrowed views, and created a corridor like effect resulting in an uncomfortable living space. There were only metal railings and a dilapidated fence separating adjacent properties, and the windows of the mews house looked directly onto the terrace leaving a distinct lack of privacy – privacy being a common requirement of almost any London property these days. Even though the visit was conducted deep in winter, there was a noticeable absence of light reaching the garden which was partly attributable to the tall buildings, but also to the aspect. There was only a period of two to three hours a day in the height of summer that the garden would be bathed in light. Plenty of headaches to overcome for the outline roof garden design.

Aralia devised a simple but clever approach to resolving the complexities of the space and its requirements. Tactical spatial design was employed by breaking the long, thin space into three sections; two larger rooms and a third sub-room thus alleviating the feeling of siting in a corridor. The ‘ceiling’ of the garden was lowered in the two main rooms by the use of small multi-stem trees in one, and metal arches planted with climbers in the other. These human-scaled features made the taller surrounding buildings more palatable and less unnerving from the eye of someone below. Placing objects of mass in the site was difficult as there were so many views, accesses and light paths which couldn’t be impeded for any number of reasons. We had to respect the mews house’s right-to-light, whilst trying to make both properties feel a little more secluded from the other. There is also a second level to the garden, a storey below the main roof terrace where the two main bedrooms have windows. These windows had to receive all of what little light the site had to offer – so we avoided solid boundaries on this side, using only singular planters and masses to create interest. The outline roof terrace design successfully resolved the site and client requirements, but the next obstacle was to engineer these solutions into a deliverable construction scheme.

The main challenge which underpinned every design move in this London roof garden was the lack of depth to the concrete podium slab; which is effectively the roof to the basement and floor to the garden. The waterproofing layer was set quite high, meaning we couldn’t drill down very far to secure structures without compromising the integrity of the building. Coupled with not being able to fix anything to the mews house, this made for quite difficult detailing. We overcame these issues by making the base plates of the structures much larger in footprint so there was far more stability, as well as reducing the amount of ornamental detailing on the higher elements to lose weight. The other issue thrown up by shallow ground was with the water feature; the concept was to have a pool sunken into the floor with a seamless stepping stone path across – which we replaced with a raised pool, clad in Jura Beige Limestone to match the floor. This worked to our advantage in some ways, providing a stronger visual divide between the dining and lounging area. 

Once the detailed roof garden design package had been signed off, hard landscaping works commenced immediately.  London garden developments such as this have very unforgiving timescales and strict deadlines, so time is always of the essence. The start of the garden works ran parallel to the latter stages of the house renovation making for an extremely hectic workplace, at times vaguely resembling a TV makeover show! The site was a logistical nightmare, as often several trades all came together in the same 90m² space, together with storage for delivered materials and furniture. Close co-ordination with the contractor on site ensured that strict construction details were followed to the finest degree; the client had chosen this contractor as they had an existing relationship, but for us it was a collaborative first. The roof garden design also features lighting, automated irrigation, a gas fire and a water cascade, meaning services had to be provided and run to location before final finishes went down – often channelling through concrete screed to get to planters or features located in the midst of paving.

When it came to the planting up the London roof terrace design, Aralia took a hands-on approach to installation given the complexity and importance of the scheme. The type of finish desired was almost akin to a show garden, where everything must look pristine and full of colour – no room for sprawling grasses or rampant perennials. We set up a structure of evergreen hedging and box balls to give year-round formality, then visited nurseries to select the flowering stock which was looking best at that point in time. Our original plans for the planting were based on a June finish, but due to delays on the house build we came to plant in mid-August, meaning a change of palette was in order. The house and garden alike both needed to give instant impact to attract a buyer. We were still involved with the project months after completion in ensuring the garden looked at its peak through autumn until the property was sold. The entire process was a laboured, but fruitful one.

The results speak for themselves though – best illustrated by a simple before and after photo. The new space is completely unrecognisable from the former, and now provides a much needed outdoor extension of living space, which is worthy of such an opulent residence.

We were thrilled that this roof garden design was an awarded a Gold and ‘Best Roof Terrace’ by the prestigious New Homes Garden Awards 2014. 

Aralia offer an experienced team of roof terrace designers who relish the challenges of such spaces, so if you have a new roof terrace which requires professional design impetus, please do get in touch on 01279 721461 or email us at Admin@Aralia.org.uk