Basement conversion contractor introductions in London.
Basement work sits at the technical end of residential construction. It involves excavation beneath an occupied building, temporary support, waterproofing and close attention to neighbours. Epelle & Co. introduces specialist basement contractors and the professionals who usually precede them.
We do not design, engineer or construct basements, and we do not advise on whether a basement is permissible. Every appointment is made directly by you.
The kinds of basement project
Cellar conversion
Making an existing cellar habitable, typically with waterproofing, new floors, ventilation and light.
Lowering
Digging down within an existing cellar or lower ground floor to gain usable head height.
New basement
Excavating beneath a house or garden where no cellar exists, with underpinning or piled walls.
Why specialist experience matters
Structural sequencing, groundwater, drainage and the movement of neighbouring buildings all have to be managed during a basement build. Firms that carry this out regularly tend to have their own methods for temporary works, monitoring and waterproofing, and established relationships with engineers.
A general builder may be well suited to fitting out a basement once the structure is complete, but the excavation and structural stage is normally a specialist package. We keep those two roles distinct when considering who to introduce.
What to prepare
Basement contractors generally expect a professional team to be in place before they can give meaningful prices. If yours is not, we will usually suggest starting there.
- Architectural drawings and a structural engineer's design or appointment
- Any site investigation, borehole or ground information
- The planning position and any conditions, from your architect or consultant
- Information on neighbouring properties and party walls
- Access to the site for excavation and spoil removal
- A budget range and target programme
Common pitfalls
- Approaching contractors before engineering and ground information exist
- Underestimating the time and cost of neighbour agreements and monitoring
- Treating waterproofing as a finish rather than a designed system
- Separating structure and fit-out without being clear who is responsible for the interface
- Choosing a firm whose comparable work is much smaller than your project
How we approach a basement enquiry
We first establish whether the professional team, ground information and planning position are in place. Where they are, we identify specialist contractors whose recent basements are comparable in method and scale, and introduce them with your agreement. Where they are not, the introduction we suggest is usually to an engineer or architect experienced in basements.
The professional team before the contractor
A basement project usually begins long before a contractor is involved. An architect develops the layout and handles any planning application. A structural engineer designs the retaining walls, underpinning or piles and the temporary works that keep the house standing while ground is removed. Ground investigation tells everyone what the soil and water are doing beneath the site.
Neighbour matters run alongside: party wall arrangements, condition surveys of adjoining properties and, on many projects, monitoring of movement during the works. A specialist waterproofing designer may also be involved.
When these pieces are in place, a basement contractor can give a meaningful price and method. When they are not, any figure offered is little more than a guess. That is why, for basements in particular, our first introduction is often to an engineer or architect.
Living above a basement build
Some owners choose to move out during excavation and major structural work. Some projects are designed so that the house remains occupied, with access arranged through the garden or a front lightwell. Ask each contractor how it would approach your site, how spoil will leave, and what the neighbours will experience day to day.
- 1. Review
We read your brief and ask what we need to understand it.
- 2. Qualify
We check budget, decision-maker and timing are in place.
- 3. Source
We identify a small number of potentially suitable firms.
- 4. Introduce
With both sides' agreement, we make a direct introduction.
Frequently asked questions
- Can you tell me if I am allowed to build a basement?
- No. Your architect, planning consultant and the local council are the right sources for that.
- Do I need a structural engineer before contacting a basement contractor?
- In most cases, yes. Basement contractors price from an engineer's design.
- Can one contractor do the structure and the fit-out?
- Some do. Others hand over to a fit-out builder. We consider which arrangement suits your project.
- Do you introduce party wall surveyors?
- Where one is needed and you do not already have one, we can introduce independent surveyors for you to appoint.
Next step
Enquiries are free and reviewed individually. Epelle & Co. makes introductions only. It does not design, build, project-manage or guarantee work; appointed parties contract directly with the client. See our Privacy Notice.