Water Ingress Specialists
When water gets in through the building fabric, the damp patch inside is rarely where the water actually enters. We trace it back to the real source, a cracked render, a failed flashing, a blocked gutter, a leaking window or a wet basement, and fix the defect itself. Survey-led, with a written 10 year guarantee.
Book a Water Ingress Survey
0300 373 7251Survey-led diagnosis with a clear, written report. No obligation.
What is Water Ingress?
Water ingress is simply water getting into a building from outside, through a fault in the external fabric. It is the opposite direction of travel to rising damp, which comes up from the ground, and to condensation, which forms on inside surfaces. Water ingress comes from outside in.
The tell-tale sign is a damp patch that gets noticeably worse after rain. But the patch on your wall or ceiling is rarely directly behind the hole. Water is patient: it tracks along timbers, down cavities and through mortar beds, often surfacing some distance from where it actually got in. That is exactly why guessing, and replastering, so often fails.
Getting it right means tracing the water back to its true source and fixing that defect, which starts with a proper survey.
Where Water Gets In
Water ingress can come from anywhere in the building envelope. The most common routes we find are:
Walls, Render & Pointing
Cracked or hollow render, spalled or porous brick and failed mortar joints let wind-driven rain soak straight through the wall.
Roofs & Flashings
Slipped or missing tiles and slates, failed lead flashings, valley gutters and chimney defects are a classic source of ceiling and upper-wall damp.
Gutters & Downpipes
Blocked, cracked or leaking rainwater goods spill water straight down the wall, saturating the masonry behind.
Windows & Doors
Perished mastic, failed seals, defective cills and blocked weep holes let water track in around openings.
Balconies & Flat Roofs
Failed waterproofing, poor falls and tired membranes on balconies, terraces and flat roofs are a frequent and tricky source.
Below Ground
Basements, cellars and retaining walls under pressure from a high water table, where the fix is structural waterproofing rather than a surface repair.
Finding the Real Source
This is the part that matters, and the part most often skipped. Because water travels before it shows, the damp patch inside is a clue, not the answer. Treat the patch and ignore the entry point and the water simply comes back at the next downpour.
We inspect the elevations, roof, flashings, gutters and openings, take moisture readings and, where it helps, use thermal imaging or controlled water testing to pinpoint exactly where water is getting in before anyone lifts a trowel. Only then do we know what actually needs repairing.
The honest version: replastering a wall that is still letting water in is money wasted. Fix the defect first, then make good.
Signs of Water Ingress
Worth getting checked before it damages plaster, decor and timber:
How We Fix Water Ingress
Survey and trace the source
We locate exactly where water is entering, using inspection, moisture readings and, where useful, thermal imaging, rather than guessing from the internal patch.
Identify the defect
We pinpoint the fault, cracked render, failed flashing, blocked gutter, perished seal, bridged cavity, and explain it clearly in a written report.
Repair the fabric
We put the defect right: repointing, render repairs, flashings, gutter and downpipe work, resealing openings or reinstating cavity trays and weep holes.
Waterproof below ground
Where the ingress is in a basement or cellar, we install proper structural waterproofing, tanking or a cavity drain membrane.
Make good inside
Once the fabric is watertight and dry, we replaster and treat any mould, only where it is genuinely needed.
Written guarantee
Completed work is backed by a written 10 year guarantee, transferable on sale.
Why Act Early
Water ingress only gets more expensive the longer it is left. Catching it early protects:
What Our Customers Say
Genuine reviews from Advanced Damp customers.
"Very good service and found a leak in our roof and made it easier to relay that information to the roof guy."
"Lionel the surveyor arrived on time and he was very courteous and thorough, he discussed everything that needed doing and was able to reassure us during a very stressful time."
"He provided a thorough, fair, and honest assessment, and his use of modern testing and technology ensured everything was measured accurately. Thanks to him, we now have a clear and reasonable remediation plan."
Related Services
Water ingress sits alongside these related damp and waterproofing services:
Water Ingress FAQs
What is water ingress?
How do you find where water is getting in?
Is water ingress the same as penetrating damp?
Can you fix water ingress without replastering everything?
Is water ingress covered by insurance?
How do you stop water ingress permanently?
Find the Leak, Fix It Properly
Book a survey and get the true source of your water ingress traced and explained, with a clear written report and honest advice, before any repair is recommended.
Last updated June 2026 · Advanced Damp Ltd · Water ingress specialists nationwide · 0300 373 7251