# Basement Construction in Chelsea

Single-storey, double-storey and lightwell basement excavations under existing London homes. Delivered for Chelsea (SW3, SW10), London, by HXL Construction under a single JCT contract, coordinated with Royal Borough of Kensington and Chelsea.

## Overview
HXL delivers basement construction in Chelsea and across the wider London. Basement construction under existing London townhouses, semi-detached and detached homes is high-margin, technically demanding work that HXL routinely delivers. Single-storey excavations under footprint, double-storey schemes, lightwell and sub-pavement vault construction in conservation-area streets. All schemes include temporary-works design, structural propping, BS 8102-compliant waterproofing, and party wall coordination across all affected neighbours.

## Capability
- Single-storey basement excavation under existing footprint
- Double-storey basement schemes
- Lightwell and sub-pavement vault construction
- Temporary works and propping design
- BS 8102 Type C cavity-drainage waterproofing
- BS 8102 Type A and Type B tanked waterproofing
- Underpinning to existing foundations
- Party wall award coordination across all neighbours

## Chelsea: local context
**Property stock.** Regency and early-Victorian stuccoed townhouses, mews houses, Edwardian mansion blocks. Many properties within RBKC's most-regulated conservation areas.

**Planning and conservation.** Cheyne Conservation Area, Chelsea Conservation Area (RBKC). Article 4 directions throughout. Basement policy under RBKC's SPD. Local planning authority: Royal Borough of Kensington and Chelsea.

**Typical scope in Chelsea:**
- Deep basement excavations under single- and double-storey footprints
- Whole-house refurbishment of listed townhouses
- Mews house ground-up rebuilds
- Façade restoration and re-rendering
- Roof plant and terrace installations

## Process
01. **Survey & design** — Ground investigation, structural engineering design, party wall service, planning consent where the scheme falls outside permitted development.
02. **Excavation** — Underpin, install temporary works, excavate, remove spoil, construct retaining walls.
03. **Waterproofing & fit-out** — BS 8102 system installation, M&E first fix, plant install, second fix and finishes.
04. **Sign-off** — Structural sign-off, Building Control completion, waterproofing system warranty, 12-month workmanship warranty.

## FAQ
**Does HXL carry out basement construction in Chelsea?** Yes. HXL delivers basement construction across Chelsea (SW3, SW10) and the wider London, as a principal contractor under a single JCT contract.

**Who is the local planning authority for Chelsea?** Royal Borough of Kensington and Chelsea. Cheyne Conservation Area, Chelsea Conservation Area (RBKC). Article 4 directions throughout. Basement policy under RBKC's SPD.

**What properties does HXL work on in Chelsea?** Regency and early-Victorian stuccoed townhouses, mews houses, Edwardian mansion blocks. Many properties within RBKC's most-regulated conservation areas.

## Related
- Basement Construction (overview): https://hxlconstruction.co.uk/services/basement-construction
- Construction in Chelsea: https://hxlconstruction.co.uk/areas/chelsea

Contact: info@hxlconstruction.com · +44 7845 585147 · HXL Construction Ltd, 102 Vine Lane, Uxbridge, London UB10 0BE