Basements · Altrincham, Hale & Bowdon
Basement conversions, Altrincham.
Cellars and new basements beneath existing houses in Altrincham, Hale and Bowdon: structural underpinning, tanking and waterproofing, drainage, services and finished rooms such as cinema rooms, offices and lounges.
Below ground
Floor area without the footprint.
On tight plots and protected streets in Altrincham and Hale, going down is often the only way to add real floor area. A basement conversion underpins the existing structure, forms a waterproof envelope and brings in drainage, ventilation, heating and power before the rooms are finished to the standard of the house above.
Our Hale basement walkthrough shows the finished result: a cinema room, a home office and a lounge beneath an existing property. It is one of several basement projects we have delivered across Altrincham, Hale and Bowdon.
What we do
How a basement gets built.
Structure and underpinning
The existing walls are underpinned in a controlled sequence, designed by a structural engineer and inspected by Building Control as the work progresses.
Waterproofing
A designed waterproofing system, typically a cavity drain membrane with sump and pump or a tanked lining, so the space stays dry for the long term.
Services and ventilation
Drainage, mechanical ventilation, heating, power, lighting and data brought in while the shell is open, with escape routes designed in.
Finished rooms
Cinema rooms, offices, gyms, lounges and guest suites, finished to match the rest of the house.
Scope
What's included.
- Structural design and underpinning
- Excavation and muck away
- Cavity drain membranes, sumps and pumps or tanked linings
- Drainage and ventilation
- Mechanical and electrical
- Staircases, partitions and finishes
- Party wall and Building Control coordination
Recent work
Projects like this, delivered.
Hale basement conversion
Hale, Cheshire
Full below-ground basement conversion beneath an existing Hale property: structural underpinning, tanking and waterproofing, services and finished living space with a cinema room, home office and lounge.
Wilmslow house
Wilmslow
A tired 1930s detached taken back to brick and rebuilt — full-width rear extension, complete refurbishment, new kitchen, staircase and oak porch.
Straight answers
Questions we get asked.
Converting an existing cellar usually does not, as long as the outside of the house does not change and it is not a listed building. Digging a new basement, enlarging one, adding a lightwell or changing the external appearance usually does, and some Altrincham and Hale streets sit in conservation areas. We check this with you at cost-plan stage.
Yes. Structure, waterproofing, fire escape, ventilation, damp-proofing and electrics are all covered by the Building Regulations, and the underpinning is inspected in stages. We arrange and manage this as part of the contract.
If the house is semi-detached or terraced, or the excavation is close to a neighbour's foundations, the Party Wall etc. Act 1996 almost always applies. We advise early so notices go out before the programme depends on them.
As a 2026 working guide, £3,000–£5,000 per square metre of finished floor area, excluding VAT, professional fees and abnormals. Ground conditions, water table, access for muck away and the finish specification drive the number, so we price the actual house rather than a headline rate.
Also from Tatton
Other services.
Office fit-out
Cat A and Cat B fit-out, workplace refurbishment and commercial interiors — much of it delivered in buildings that never closed.
CommercialShopfitting
Shopfitting and retail refurbishment, from strip-out and enabling works to a finished store — built around a fixed opening date.
CommercialCommercial refurbishment
Whole-building and occupied refurbishment of workplaces and commercial property — including the EPC and MEES upgrades that make a building lettable.
ResidentialNew build homes
One-off private homes, from £400k to £3m and beyond — from groundworks and structure through services, finishes and handover.
ResidentialHousing developments & land
Schemes of two to thirty plots. We buy sites, joint-venture with landowners and build out — with a free site appraisal in five working days.
ResidentialExtensions in Altrincham
Substantial extensions, structural remodelling and whole-house refurbishment across Altrincham, Hale and Bowdon.
ResidentialExtensions in Hale
Major extensions and high-specification whole-house remodelling in Hale, Bowdon and the surrounding Cheshire villages.
CommercialCat A & Cat B fit-out
Landlord Cat A, tenant Cat B and complete shell-to-handover fit-out, delivered UK-wide.
CommercialCommercial fit-out
Office, healthcare, hospitality and retail fit-out, delivered UK-wide and around live operations.
CommercialConversions
Office-to-residential, commercial change of use and permitted-development conversions, delivered UK-wide.
CommercialHealthcare fit-out
Care homes, surgeries and clinical buildings, fitted out and refurbished in live settings, UK-wide.
CommercialHospitality fit-out
Hotels, restaurants and bars, front and back of house, delivered to a fixed opening date, UK-wide.
ResidentialBuilders · Altrincham
Owner-managed building contractor based in Altrincham: extensions, renovations, basements, new builds and office fit-out.
ResidentialRenovations · Altrincham
Whole-house renovation and remodelling across Altrincham, Hale and Bowdon, delivered as one programme.
CommercialOffice fit-out · Altrincham
Cat A and Cat B office fit-out and refurbishment for businesses in Altrincham and south Manchester.
Thinking about going down?
Send the address and any drawings. We'll tell you what is realistic for the plot and give you a written cost plan.