Services/Building services

Basement waterproofing and tanking in West London

Cellars, basements, retaining walls and anything below ground. Type C cavity drain as standard, so water is managed rather than fought.

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2–6weeks, typically
Type Ccavity drain systems
Backuppump as standard
Guaranteedsystems

Listed, vetted and reviewed on

Ogival Ltd, registered in England & Wales no. 15191703 · Public liability insured · NICEIC registered electrical work · Gas Safe registered plumbing and heating

Below ground, water always wins a straight fight. The modern approach doesn't try to hold it back with a coating — it lets it in behind a membrane, collects it in a channel, and pumps it away. That's why the pump, the channel and the backup matter as much as the membrane itself.

Why coatings alone fail

A cementitious coating relies on a perfect bond over a whole wall. One weak area and hydrostatic pressure finds it.
A membrane with no drainage channel just moves the water to the floor.
A single pump on a single circuit is not a system. Power cuts happen at the same time as storms.

Waterproofing & tanking by Ogival in West London

Below-ground waterproofing and basement construction

What's included in a waterproofing job

Our waterproofing team handle the whole of it, so there's no second company to chase and no gap between trades for something to fall through.

Waterproofing design
Cavity drain membrane to walls and floor
Perimeter drainage channel
Sump chamber and pump
Backup pump and alarm
Cementitious tanking where appropriate
External drainage improvements
Insulated linings
Floor screeds
System guarantees

Send a photo of the cellar walls

A photo of each wall and the floor, plus anything that's wet or salty, and we'll tell you what system it needs.

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At a glance

ServiceWaterproofing & tanking
GroupBuilding services
Typically2–6 weeks
CoveringWest London
BasedLondon W10

Why Ogival

25 years in London construction
Thirty-one trades under one contractor
Drawings and calculations in-house
A written schedule of works and payments
NICEIC and Gas Safe registered

How we work

Options

The three types of waterproofing, honestly compared

Type A — barrier

A cementitious coating applied to the structure. Works where it's perfect and applied to sound substrate.

Type B — structural

Waterproof concrete forming the structure itself, designed in from the start.

Type C — cavity drain

A membrane, perimeter channel, sump and pump. Manages water rather than resisting it, and the usual answer for a habitable basement.

Quickest way to get an answer

Send a photo of the cellar walls.

A photo of each wall and the floor, plus anything that's wet or salty, and we'll tell you what system it needs.

No form, no callback queue, no salesman. Emanuel looks at it himself and tells you what he sees — including the times the answer is that you don't need us.

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OOgivalonline

Cellar floods a bit every winter. Can it be tanked?

It can, but I'd want to see where the water's coming in before anyone specifies anything.

If it's through the floor as well as the walls, a painted coating won't hold it — you'd want a cavity drain system with a sump and pump.

Is there a drain in the street you could discharge to, or does it need pumping up? That changes the design.

Message

A typical exchange. Usually answered the same day.

How it runs

How a waterproofing job runs, stage by stage

Four stages, and you'll always know which one you're in.

01
Survey and waterproofing design
Water source, ground conditions and what the space will be used for decide the specification.
02
Prepare the structure
Existing finishes removed, walls made good, floor levels checked against the channel and sump.
03
Install the system
Membrane, channel, sump and pump installed as a system and tested together.
04
Line and finish
Insulated linings, screeds and finishes over the top, with the system accessible for maintenance.

Below-ground waterproofing and basement construction

Recent projects

Basements we've waterproofed

Below-ground work where the waterproofing was designed in from the start.

Providence Villas, W12Read the case study →

Minotti Kitchens, W1Read the case study →

All our case studies

Permissions

Standards, pumps and maintenance

Waterproofing a habitable basement is covered by BS 8102, and the sensible interpretation is a combined approach with drainage and a pump rather than relying on a coating alone. Pumps need power, backup and servicing — build that in at the start.

Rules change and every property is different. We confirm what applies to yours in writing at the survey rather than leaving you to guess.

BS 8102 sets out the grades of waterproofing protection for below-ground structures
Habitable space is Grade 3 — dry, with environmental control
Combined systems are normally specified rather than a single barrier
Pumps need a backup, an alarm and an accessible maintenance route
Building regulations also cover ventilation, escape and insulation below ground

Budget

How much does a waterproofing cost in London?

We don't publish prices, because a number without a survey is a guess and you'd be right not to trust it. These are the things that actually move it.

Area of wall and floor

Whether a sump has to be dug into the slab

Pump redundancy and alarms

External drainage work

Insulation and finishes over the top

Access for materials and spoil

How long does a waterproofing job take?

2–6 weeks on site for a typical job in West London, though the drawings, permissions and party wall process before it can add longer. We give you a written programme with the quote so you can see both.

A site visit and a written quote cost nothing, and the quote comes with a written schedule of works so you can see what every stage is for.

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Before you appoint anyone

Four questions to ask before you hire anyone for waterproofing work

Ask them of us as well. The answers tell you more than the number at the bottom of the page — and a contractor who can't answer them quickly is telling you something too.

Ask us right now

01
Ask which grade and which type they're designing to, and why
02
Ask where the sump is and how it will be serviced once the floor is down
03
Ask what the backup is if the power goes off in a storm
04
Check the guarantee covers the system, not just the membrane

What clients say

Word of mouth, written down.

Left by Ogival customers on MyBuilder and TrustATrader

I have used this company for years for many different jobs including painting my whole house, tiling my bathroom, laying flooring, astroturfing my garden and putting up fences. Very knowledgeable, professional and polite. If you want a company that care, I'd stick with Ogival.

★★★★★Repeat client, MyBuilder

Ogival has a friendly and professional team. Our new bathroom looks great and we're very happy with the choice of products used and the quality of their work.
★★★★★New bathroom, MyBuilder

Great communication, polite workers and excellent tidying up afterwards. Definitely recommend.
★★★★★Painting and maintenance, MyBuilder

They were professional, polite, easy to get hold of and easy to deal with. They did a great deal of work for me including building an internal wall, moving a bathroom, carpentry, electrics and plumbing, they re-rendered my balcony, relaid the decking and repainted the whole flat.
★★★★★Full flat refurbishment

I have used this company for years for many different jobs including painting my whole house, tiling my bathroom, laying flooring, astroturfing my garden and putting up fences. Very knowledgeable, professional and polite. If you want a company that care, I'd stick with Ogival.
★★★★★Repeat client, MyBuilder

Ogival has a friendly and professional team. Our new bathroom looks great and we're very happy with the choice of products used and the quality of their work.
★★★★★New bathroom, MyBuilder

Great communication, polite workers and excellent tidying up afterwards. Definitely recommend.
★★★★★Painting and maintenance, MyBuilder

They were professional, polite, easy to get hold of and easy to deal with. They did a great deal of work for me including building an internal wall, moving a bathroom, carpentry, electrics and plumbing, they re-rendered my balcony, relaid the decking and repainted the whole flat.
★★★★★Full flat refurbishment

He replaced eroded bricks and once the wall was dry replastered ready to decorate. Work was delayed because he uncovered wet rot in the ceiling joists. He fixed the cause of those leaks. Throughout this saga Ogival has been professional, reliable, extremely thorough and honest.
★★★★★Exterior leak repairs, MyBuilder

I found them really helpful and honest. They went out of their way to help. They also finished on time and left the place spotless.
★★★★★Renovation, TrustATrader

I decided to go with them as I liked their ideas and Emanuel knew what he was talking about. He made floor to ceiling units, redecorated my room and laid laminate flooring. I have no hesitation in recommending them.
★★★★★Bespoke joinery, TrustATrader

Good finishing.
★★★★★Mohammed D., MyBuilder

He replaced eroded bricks and once the wall was dry replastered ready to decorate. Work was delayed because he uncovered wet rot in the ceiling joists. He fixed the cause of those leaks. Throughout this saga Ogival has been professional, reliable, extremely thorough and honest.
★★★★★Exterior leak repairs, MyBuilder

I found them really helpful and honest. They went out of their way to help. They also finished on time and left the place spotless.
★★★★★Renovation, TrustATrader

I decided to go with them as I liked their ideas and Emanuel knew what he was talking about. He made floor to ceiling units, redecorated my room and laid laminate flooring. I have no hesitation in recommending them.
★★★★★Bespoke joinery, TrustATrader

Good finishing.
★★★★★Mohammed D., MyBuilder

Read them in full on MyBuilder, TrustATrader and Houzz.

Where we work

Waterproofing & tanking across West London.

Basement waterproofing across West London, where high water tables, Victorian cellars and party wall neighbours all shape the specification.

Ogival, W10 5DW
Everyday patch, within 10 miles
Regular work, 10 to 20 miles
By arrangement, out to 30 miles

Where we do this most

Outside this? Ask anyway. We'll tell you honestly whether we're the right firm for the journey.

Questions we get asked

The things people ring up about.

The questions that come up on the phone most often, answered the way we'd answer them on site.

What is Type C waterproofing?

A cavity drain system — a dimpled membrane that lets water pass behind it into a perimeter channel, then to a sump and pump. It manages water rather than resisting it, which is why it's the standard for habitable basements.

Do I need a pump?

For a cavity drain system below the water table, yes, and ideally a second one plus an alarm. Where there's a gravity outfall available we'll use it.

Can you tank a cellar so we can use it as a room?

Yes, though a habitable room also needs to meet requirements for ventilation, escape and often head height. We'll tell you what else is involved before you get attached to the idea.

Is it guaranteed?

The membrane systems we install come with manufacturer guarantees when installed to specification, and we hand over the maintenance schedule for the pump.

The rest of what we do

Waterproofing & tanking, and thirty other things we do

Most jobs pull in more than one of these. Having them all under the same roof is what stops a project stalling for three weeks waiting on somebody else's diary.

Construction, structural & civilsBasement conversions

Building servicesDamp proofing

Building servicesDrainage & rainwater

Building servicesPlumbing & heating

Building servicesElectrical

Building servicesGardens & landscaping

Building servicesExternal cleaning

Building servicesRoofing

See all thirty-one services

Start here

Tell us what you're planning.

A site visit and a written quote cost nothing. If the job isn't right for us, we'll say so and point you somewhere better.

Free, no-obligation site visit and written quote
You deal with Emanuel, not a sales rep
A written schedule of works and payments before anything starts
Covering Kensington, Chelsea, Hammersmith and Fulham

07428 135100 info@ogival.co.uk

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