Cambridge Damp and Mould: Surface-Water Risk, Victorian Terraces and Rental Demand

Cambridge sits in one of the drier parts of England, with about 559 mm of rain a year at the nearby Niab station, yet 12.2% of its properties are at medium or high risk of surface-water flooding, roughly double the England figure of 5.9%. The explanation is the way water behaves on a dense, hard-surfaced city, and it matters for landlords of the city's many Victorian terraces and flats.

Cambridge in numbers

• Private rented households: 31.4% (England 20.5%); social rented: 22.7% (England 17.1%)
• Terraced homes: 27.6% (England 23.0%); flats: 34.3% (England 21.4%)
• Homes with no central heating: 1.6% (England 1.5%)
• Overcrowded households: 4.5% (England 4.4%)
• River or sea flood risk: 1.6% (England 1.9%); surface-water risk: 12.2% (England 5.9%)
• Rainfall: about 559 mm a year at Niab, roughly three miles away

Low rainfall, high surface-water risk: what is going on?

Surface-water risk is about intense downpours landing on roofs, roads and paving faster than drains can take them, not about total annual rainfall. A low annual figure can therefore hide short, heavy events that push water against walls and through lower openings. Landlords should not assume a dry climate means a dry building.

A check after heavy rain

1. Look at gutters, downpipes and gullies for blockages and overflow marks.
2. Check that paving and ground levels slope away from the walls.
3. Inspect lower walls, cellars and ground-floor corners for new staining.
4. Record what you find with dates and photographs.

Dense Victorian terraces and strong demand

Cambridge has a high density of Victorian terraced housing, and planning constraints have historically limited new development. Strong rental demand from university staff, students and the tech sector keeps older homes on the market, which adds pressure on maintenance standards. Demand for a property does not change what a landlord owes a tenant: a home that is let quickly still has to be free from serious damp.

What landlords must do

The Homes (Fitness for Human Habitation) Act 2018 requires a rented home to be fit to live in, and the council can assess damp and mould under the Housing Health and Safety Rating System.

Awaab's Law currently applies to social housing, with private landlords expected to follow. Our guide to Awaab's Law and the private rented sector covers the current position.

To find a specialist, see our Cambridge damp and mould page.