Hertfordshire’s rivers, including the Colne, Gade, Chess and Lea, run through some of its busiest towns. Rickmansworth, Watford, Hemel Hempstead and Hertford all have homes close to the water, and the south of the county sits on London Clay.
Riverside towns
Properties near the rivers can have higher groundwater, especially in winter. That shows up as damp in cellars, solid floors and the lower parts of walls.
Clay in the south, chalk in the north
The south of the county is largely London Clay, which holds water and moves with the seasons. The north and west are on chalk, which drains more freely. Clay areas tend to see more damp ground floors and seasonal cracking.
Market towns and timber frames
St Albans, Hitchin, Berkhamsted and Hertford have historic centres with timber-framed and Georgian buildings. These need breathable repairs, and timber frames are vulnerable to decay wherever water gets in.
Interwar and commuter homes
Much of south Hertfordshire was built up between the wars. Corroding mild steel wall ties, blocked sub-floor vents and condensation in extended homes are all common findings.
Practical steps
- Keep air bricks clear and gutters flowing
- Keep soil and paths below the damp proof course
- Get damp in cellars assessed before converting or finishing them
We survey properties across south and west Hertfordshire. See damp proofing in Hertfordshire and basement waterproofing in Hertfordshire.
