Bangor, Gwynedd
Most damp in Bangor
is ventilation, not rising damp.
A university city of Victorian terraces and slate-walled stone, in one of the wettest corners of Britain, with a rental market running at high occupancy nine months a year. That combination produces a very particular kind of damp — and it is almost never what the treatment quote says it is.
The local stock
What Bangor is built from.
Victorian terraces, slate-hung and rendered
Solid stone walls, many slate-hung on the weather elevation and re-rendered in cement at some point since. Cement traps water in a wall built to release it, and the render then cracks at the junctions where it meets slate. The damp shows up internally a full storey below the actual defect.
High occupancy, low ventilation, nine months a year
The commonest damp problem in Bangor by a wide margin. Six people in a four-bedroom terrace, drying washing indoors through a Gwynedd winter, with an extractor that was disconnected years ago and windows that no longer open. It is condensation, it is a ventilation defect, and it is not solved by injecting the walls.
Exposure off the Menai Strait
Driven rain straight off the water onto elevations with nothing in front of them. Penetrating damp here concentrates on the south-west face and around openings — cills, reveals and the head of bay windows do most of the suffering.
Cavity walls, bridged
Interwar and post-war cavity housing where the failure is usually mortar droppings on wall ties, a bridged cavity at an extension junction, or ground raised above the damp-proof course by a patio or conservatory added in good faith.
The weather
Rainfall does half the work.
Bangor sits at the foot of Eryri, and parts of that catchment take among the highest rainfall anywhere in the United Kingdom. A wall that would dry out between showers in Cardiff never gets the chance here. That changes the diagnosis: in this climate a wall's ability to breathe matters more than any chemical ever will, and an impermeable render is a fault rather than a repair.
It also means seasonal timing is real. A survey in February and the same survey in July can read very differently, and the February one is usually the honest one.
If you let property here
Bangor landlords have a paper problem.
Every private landlord in Wales must be registered with Rent Smart Wales, and anyone managing a property must be licensed. Under the Renting Homes (Wales) Act 2016 the dwelling must be fit for human habitation throughout the contract — and damp and mould is the first hazard on that list, not a footnote to it.
In a student market that means the complaint you get in November is a fitness question, not a lifestyle argument. An independent survey that identifies a broken extractor or a cracked render tells you what to fix and evidences that you acted. It is also the document that answers a contract-holder who has been reading up on their rights.
What you get
The survey itself.
Internal moisture profile
Readings taken at height intervals across affected walls, so a pattern emerges rather than a single number.
Salt analysis
Hygroscopic salts distinguish genuine rising damp from a leak or from condensation. It is the test that most treatment quotes skip.
External defect inspection
Render, pointing, downpipes, ground levels, slate. The cause is outside far more often than it is in the wall.
Air and surface conditions
Temperature, humidity and surface readings — the evidence that separates a ventilation problem from a water-ingress one.
Independent and insured. We survey; we do not sell treatments, so there is no quote waiting at the end of the report.
Nearby
Also covered from here.
Bangor and the surrounding area
Find out what it actually is.
Fifteen minutes from Llangefni. Tell us the postcode and what you are seeing.