The mechanical heart of every reliable London basement waterproofing system: designed, installed, tested and warranted for 25 years by Delta Registered Installers with a directly-employed crew.
Delta Registered Installers · Twin pumps with battery back-up · Free site visit and written specification.
The sump and pump are the mechanical parts of your basement waterproofing, the pieces that quietly move water from where it collects to where it leaves the building. Everything else in a Type C system depends on them working. That's why we install twin pumps, battery back-up and audible alarms as standard on every habitable basement.
The design, installation, commissioning and maintenance of sump chambers and pump systems: twin-pump configurations with automatic failover, battery back-up in mains failure, and audible alarms, as part of a full Type C cavity drainage waterproofing system.
Homeowners with a new basement excavation, an existing basement being brought up to specification, and property owners whose existing single-pump system has failed or been flagged by a surveyor.
During new basement waterproofing (designed in from day one), as an upgrade to a single-pump system, or as an emergency replacement after pump failure.
A single-pump basement is a single point of failure. Every properly designed London basement uses a twin-pump system so that a mechanical, electrical or blockage failure of one pump doesn't flood a habitable floor.
Every UHM project runs through the same structured stages. You'll always know what's happening next, who's doing it and when it completes.
Sump location, chamber depth, discharge route and pump specification designed to match the waterproofing system's expected flow rate.
Sump chamber set to correct falls, connected to the perimeter drainage channels of the Type C cavity drainage system.
Two pumps installed with automatic failover, audible alarm, and battery back-up unit. Discharge route to soil, storm or highway drain.
Both pumps tested against the design flow, alarms triggered and confirmed, battery back-up verified under simulated power loss.
Commissioning report, warranty certificate and annual maintenance schedule handed over in writing.
A basement pump installation is a mechanical system with clearly defined components. Here's what we install and why.
The sump is the reservoir that collects water from the perimeter drainage channels. Its size, depth and fall are designed against the volume of water the drainage system may deliver in a peak event.
Twin submersible pumps installed with independent float switches and automatic failover. If pump A fails, pump B takes over and the alarm triggers. Pumps are sized to move design flow with comfortable headroom.
Battery back-up units keep pumps running during mains failure. Audible alarms sound on high water level, pump fault or low battery. Remote monitoring add-ons are available for owners who need alerts to a phone.
Every pump system is commissioned with a documented test: both pumps run under load, failover triggered, alarms proven and back-up verified against a simulated power loss. Annual servicing is recommended and available in-house. Pumps typically service well beyond a decade with proper maintenance.
Every habitable basement we deliver gets a twin-pump system with automatic failover, because the second pump is the difference between damp and flooded.
Battery back-up units keep pumps running when mains power cuts, the exact moment they're most needed.
Standard audible alarms warn of high water level or pump failure. Remote alert options are available for second homes and let-out properties.
Pumps specified against the design flow rate of the Type C cavity drainage system, not a generic default.
Annual servicing available with an in-house crew, not a phone number that no one answers when a pump fails.
A properly commissioned pump system runs for years without needing thought. Which is the point.
Every pump has a service life. Every impeller collects debris. Every float switch eventually sticks. A basement with one pump and no back-up is a basement that will one day be flooded. The only variable is what's in the room when it happens.
One pump. One float switch. One motor. When any of them fails and there's no back-up, water backs up into the basement. Floor finishes, furniture and joinery become insurance claims.
London storms cut power. If the pumps stop, and there's no battery back-up, the sump fills faster than it can drain by gravity. A basement doesn't need much to become unusable.
Without an audible alarm, a stuck float or a failed pump goes unnoticed until damp appears on skirtings. By then the fix is a strip-out.
Installing a single pump on a habitable basement to save money.
Skipping battery back-up 'because power cuts are rare'.
Fitting a pump without an audible alarm.
Undersizing the pump against the design flow rate.
Ignoring annual servicing after commissioning.
Installing a pump behind finished walls with no access for maintenance.
Straight answers we give on almost every free site visit, cost, timeline, guarantees and what's included.
A habitable basement is a livable floor. A single pump is a single point of mechanical failure, when it fails, the basement floods. Twin pumps with automatic failover is the industry-recognised standard for habitable London basements and what we install as default.
Priced per project: cost depends on chamber size, discharge routing, whether it's a new installation or an upgrade, and the specific pump and alarm equipment specified. Site visits and quotes are always free.
Yes: we recommend annual servicing to test pumps, clean sumps, verify battery back-up and prove the alarms. This is available in-house and included in the maintenance schedule handed over at commissioning.
The battery back-up unit takes over automatically and keeps the pumps running. If mains power stays off longer than the battery reserve, the audible alarm triggers to warn the household.
Yes, retrofit sump-and-pump installations are possible, usually as part of a Type C cavity drainage retrofit. We survey first and issue a written specification.
The pump system is delivered under our 25-year waterproofing warranty as Delta Registered Installers, with manufacturer warranties on the individual pumps and back-up units also documented at handover.
As part of a new waterproofing installation, it's included in the main programme. As a standalone retrofit or emergency replacement, most jobs complete inside two to three weeks.
Yes: where an existing pump has failed, we can survey and quote a like-for-like or upgraded replacement quickly. Response depends on stock and site access; we're honest about timing.
A director will visit, review the existing installation or design a fresh system, and issue a written quote, for free. If you already have a working twin-pump setup, we'll tell you.
