Damp proofing in London: only where the cause is proven, with a 10-year insurance-backed guarantee, IBG Term 10, transferable with the property.

Only where it is truly needed, and only once the cause is proven.

or call 0330 520 2584

Four kinds of damp, each put right at its source.

Rising damp

Ground moisture climbing the base of a wall, where the damp-proof course has failed, been bridged or was never built.

We only call it rising damp when the evidence says so.

The signs: A tide mark low on ground-floor walls, usually no higher than about a metre, with spoiled plaster and skirting.
First: Remove anything bridging the course: a raised path, a flower bed, or render taken down to the ground.
Then, if proven: A new damp-proof course injected into the wall, and replastering with materials matched to it.

Penetrating damp

Rain getting in through the walls or the roof, wherever the building’s outer skin has let it through.

The signs: Patches that grow after rain, at any height, often on the most exposed walls.
The usual causes: Leaking gutters and downpipes, weathered pointing, cracked render or failed flashing.
Put right by: Repairing the source, with repointing and render or gutter and roof repairs, then letting the wall dry. No injection needed.

Condensation

Moist air from everyday life meeting cold walls and windows, and turning back into water.

The signs: Streaming windows, and black mould in corners and behind furniture.
The usual causes: Too little ventilation, cold spots in the walls, and fans too weak for the room.
Put right by: Ventilation, extractor fans or positive input ventilation, and mould removal. Damp proofing will not cure it.

Damp after wall insulation

Insulation added to a solid wall, inside or out, can trap moisture where it was never meant to sit.

The signs: Damp or mould on walls that were dry before the insulation went in.
The usual causes: Insulation that stops a solid wall drying, cold edges where it stops short, or gaps that let water in behind it.
Put right by: Finding where the moisture is trapped, then putting right the detail that is trapping it.

Six steps, in the right order.

A free survey

We find the cause and prove it, inside and out. About the survey

Your findings, in writing

Within 48 hours. Itemised costs come last, and only where work is justified.

The cause, removed

Bridged courses cleared, ground levels lowered, leaks and gutters put right.

A new damp-proof course

Injected into the wall, only where rising damp is proven.

Replastering

With materials matched to the wall, including lime for older homes.

Guaranteed

10-year insurance-backed guarantee, IBG Term 10, transferable with the property.

Sometimes the most valuable finding is no.

A Victorian ground-floor flat with a damp bay wall. The cause was air bricks blocked beneath the paving, starving the floor of air.

“Internal damp proofing is not currently needed.”

From one of our reports. We recommended clearing the air bricks and restoring ventilation beneath the floor, then letting the wall dry.

Lime where it belongs. A damp-proof course only where it is proven.

Solid walls in older homes were built to take in moisture and let it out again.

Lime, not cementCement renders and impermeable plasters can trap moisture in old solid walls. For period homes we repair in lime plaster and lime render where the wall calls for it.

The cause before the cureHistoric England, RICS and the Property Care Association set out the same principle: find the source of the moisture before any remedial work.

Listed buildingsWorks to a listed building may need consent from your council. We survey listed homes and tell you plainly what the building needs.

A guarantee written to last.

IBG Term 10

Our treated works carry a 10-year insurance-backed guarantee, IBG Term 10, transferable with the property. Included as standard, it covers the treated works set out in your written guarantee. Because it is insurance-backed, it stands even if we cease to trade, and it passes to the new owner if you sell.

TrustMark registered
Surveys carried out by CSRT/CSSW-qualified surveyors
PCA-qualified surveyors

About damp proofing, answered plainly.

Do I need damp proofing?

Only if rising damp is proven, and only once anything bridging the old damp-proof course has been put right. Many damp walls are caused by condensation, leaks, gutters or ground raised outside, and none of those is cured by damp proofing.

If you don’t need damp proofing, we’ll tell you.

What is a damp-proof course?

A layer near the base of a wall that stops moisture from the ground climbing into it. Many Victorian and later homes were built with one, often of slate or bitumen. Some older walls were built without one.

How does damp proof injection work?

A new damp-proof course is formed by injecting a water-repellent material into a mortar joint near the base of the wall. It is only worth doing where rising damp is proven, and only once anything bridging the course has been removed.

Will I need replastering?

Usually, where the plaster has been damp for a long time. Old plaster can hold contamination that keeps drawing moisture from the air, so damaged plaster is replaced with materials matched to the wall, including lime for older homes.

How long do walls take to dry?

Solid walls dry slowly, often over many months, depending on their thickness, the weather and how the room is heated and ventilated. Decorating too soon can trap moisture, so we tell you when it is safe.

Will damp proofing get rid of black mould?

Not usually. Black mould is more often linked to condensation than to rising damp, and condensation is put right with ventilation, not damp proofing.

Can you damp proof a listed or period home?

Yes, with care. Old solid walls are often better served by lime and by removing the cause than by a new damp-proof course. Works to a listed building may need consent from your council, so we tell you plainly what the building needs.

Historic England, RICS and the Property Care Association set out the same principle in their joint position statement: find the cause of the moisture before any remedial work.

Source: Historic England, Investigation of moisture and its effects on traditional buildings

Is it disruptive?

Replastering is messy work, so we protect your floors and furniture, and tell you before we start how long each room will be out of use.

When do I see a price?

Last. The survey comes first, then your written findings. Itemised costs follow only where work is justified, and the decision is entirely yours.

What does the guarantee cover?

Our treated works carry a 10-year insurance-backed guarantee, IBG Term 10, transferable with the property. It covers the treated works set out in your written guarantee and is included as standard. Because it is insurance-backed, it stands even if we cease to trade.

Which areas do you cover?

Every London borough, and anywhere within the M25. Further afield, call us on 0330 520 2584 and we’ll tell you honestly whether we can help.

Damp proofing in London: only where the cause is proven, with a 10-year insurance-backed guarantee, IBG Term 10, transferable with the property.

Thank you.

Four kinds of damp, each put right at its source.

Rising damp

Penetrating damp

Condensation

Damp after wall insulation

Six steps, in the right order.

Sometimes the most valuable finding is no.

Lime where it belongs. A damp-proof course only where it is proven.

A guarantee written to last.

About damp proofing, answered plainly.

May we take a closer look?

Damp proofing in London: only where the cause is proven, with a 10-year insurance-backed guarantee, IBG Term 10, transferable with the property.

Thank you.

Four kinds of damp, each put right at its source.

Rising damp

Penetrating damp

Condensation

Damp after wall insulation

Six steps, in the right order.

Sometimes the most valuable finding is no.

Lime where it belongs. A damp-proof course only where it is proven.

A guarantee written to last.

About damp proofing, answered plainly.

When the answer isn’t damp proofing.

May we take a closer look?