Concrete Basement Structure
Subterranean Engineering

Basement
Construction

Extend Downwards

Unlock Potential Beneath Your Feet.

Retrofit basements are the ultimate engineering challenge. LG Groundworks specializes in complex underpinning and subterranean excavation to maximize your property's footprint.

Whether creating a luxury cinema room, gym, or additional living space, we manage the entire structural shell. From temporary propping design to the final waterproof concrete pour, our team ensures your investment is built on—and in—solid ground.

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Basement Excavation Site
Our Capabilities

Substructure Solutions

Retrofit Basements

Excavating beneath existing structures using sequential underpinning techniques to create new habitable space safely.

RC Shells

Reinforced concrete retaining walls and slabs, engineered to withstand lateral earth pressure and structural loads.

Underpinning Detail

Structural Waterproofing

We install Type A (Barrier) and Type B (Integral) waterproofing systems, including Delta membranes and Sika watertight concrete, guaranteeing a dry environment compliant with BS 8102.

Temporary Works

Design and installation of propping, shoring, and needling to support the existing building during excavation.

01. Design

Structural calculations and temporary works design to ensure building stability.

02. Support

Installation of piling or underpinning to transfer existing loads to new depths.

03. Excavate

Bulk removal of earth from beneath the footprint, often via conveyor systems.

04. Construct

Pouring of the reinforced concrete shell and installation of waterproofing.

Completed Concrete Shell
Technical Data

Basement FAQs

Yes, creating a new basement or significantly extending an existing one usually requires planning permission. A 'Basement Impact Assessment' may also be required by your local authority.

Yes. This is called a retrofit basement. We use a sequential underpinning method to safely excavate beneath the existing footings without compromising the structure above.

Absolutely. We use industry-leading systems (like Sika or Delta) installed to manufacturer specifications, offering robust warranties on the structural waterproofing.

Ready to Extend Downwards?

Contact us for a structural consultation.

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