Basement Design Architect

With prices rising and Property shortages an ongoing reality, some Homeowners look at options to win additional quality space by digging down.

As families grow and expand, exploring additional basement accommodation can be a viable option. The balance of moving costs versus the high cost of undertaking a basement dig needs careful consideration. Adding a new level of accommodation below an existing property is a game changer which needs approaching with all the facts on the table.

Atelierdb are highly knowledgeable in this specialist area and advice clients of all eventualities that need to be considered at the viability stage.

A good proportion of period properties across London have existing small basements with poor floor to ceiling height. These are typically not much larger than the ground floor hall footprint, with a rudimentary open tread stair providing steep access. These are usually cramped and  suffer with damp due to ground water levels as well as their physical connection to the front ground floor level via a coal chute.

Our in depth experience helps us best advise clients embarking on such a project, from concept through to completion. Ensuring that you have the right team on board is key to protect your asset and those in proximity. As an RIBA Chartered Practice we help clients assemble all critical consultants and inform on those who may be brought on board to ensure all parties are best protected from this significant structural undertaking.

We have helped clients enlarge existing coal chute basements to provide a utility room through to undertaking 100m2 + basements below entire footprints of their house and garden.

A basement can provide additional habitable rooms, games areas, family rooms, swimming pools, gyms or simply provide additional storage and technical rooms to support the existing accommodation.

Each property is unique. We provide basement designs to help explore the best solutions and work together with the client to develop the brief and ensure a balanced quality design is delivered. Some properties will be able to enjoy front and rear lightwells. Others may have substantial gardens to allow step access via lightwells setting up some really exciting architectural opportunities. Checking the Local Authority Planning policy documents is key to understanding any constraints that may arise.

When adding a basement we explore efficient designs and identify any unique opportunities that make best use of space, playing with light and form to link old and new spaces. At all times we listen – we explore the different needs of each client and respond to provide bespoke tailored designs that fit with how families need to live and grow.

An important consideration when purchasing a property is to understand what exists at the adjoining houses. Existing basements to adjoining properties can have a significant impact on the development potential of a property. Critically, gaining information on drainage and any underlying services within the site is paramount. Historically a lot of period properties shared drainage runs and how these are modified or incorporated into a basement project needs to be considered at an early stage to ensure design potential is best delivered. Thames Water must be consulted should there be a sewer running across the site or below the property. Atelierdb can help with all.

In conjunction with the front end Design stages Atelierdb Architects help advise clients on the chronoligical events of a Basement project. Once a design is finalised, Party Wall notice needs to be served on any affected adjoining owners. This will very likely be a time consuming process given the need to seek permission for special foundations below Party Walls. The Planning Application process will release an army of mailshots directed at anyone who may be deemed affected by the basement works. These will mostly come from Party Wall Surveyors and Main Contractors but many other companies keep abreast of information published on the Borough Planning pages and will send out letters of encouragement, paranoia, and expertise. Atelierdb have developed strong working relationships with professional consultants who seek to simplify and inform on best practice through all stages. A basement construction project brings detailed scrutiny from a number of professionals for obvious reasons. Skilled Basement Contractors must arrange for and follow detailed temporary propping designs with regards sequencing and propping of the works. The designs must be followed rigorously – without deviation.

Good neighbourliness should be encouraged at an early stage. On learning a basement project is being considered next door, an adjoining owner can become very concerned which is understandable. The Party Wall process is in place to address and protect all parties impacted by a basement project. It can be the case that clients have to cover costs for a number of adjoining owners Party Wall Surveyors as well as their checking engineers. In addition funds may be required to be put into an escrow account – providing an agreed level of money for any remediation work required. This process will take significant time to allow the scrutiny of all design proposals and the credentials of the Basement Contractor. Once PW Awards are finalised they are valid for one year.