Are Finlock Concrete Gutters Causing You Problems?
By Adkins Consultants 6 June 2025
If you own a home built in the 1950s or 60s, there’s a good chance it may be fitted with Finlock concrete gutters. Originally intended to streamline construction, these gutters now present common issues for homeowners—from leaks and damp to costly structural problems.
At Adkins Consultants, we’ve seen it all. This guide explains what Finlock gutters are, the problems they cause, and how you can fix them for good.
What Are Finlock Gutters?
Finlock gutters were a post-war innovation, manufactured by Royston, designed to integrate the gutter, lintel, and cavity closer into a single precast concrete unit. Builders loved them for their simplicity. Homeowners today? Not so much.
Integrated concrete gutter, lintel and cavity closure system.
Each unit is about 200–250mm wide and designed to overhang the outer wall, with sections placed end-to-end across the eaves and above windows.
Why Are Finlock Gutters a Problem?
While clever in theory, time has shown these systems are prone to a range of failures:
- Poor drainage – Limited outlets and flat levels mean frequent overflows.
- Structural movement – Sections often settle and misalign, leading to leaks.
- Cold bridging & condensation – Solid concrete transfers cold into the property, encouraging mould.
- Window replacement complications – Installers unfamiliar with Finlock gutters often remove the only lintel supporting the wall.
- Mould growth – Often visible as a black line just below the ceiling.
Modern fascia and guttering installed after Finlock removal.
Signs You May Have Finlock Gutters
Wondering if your gutters are the culprit? Look out for:
- Damp patches at ceiling level
- Leaks around windows
- Overflowing gutters even when clean
- Vertical cracks on internal walls (every ~240mm)
Typical appearance of Finlock guttering left in place.
Your Repair Options
You have two main options:
- Lining the Existing Gutter
Pros: Less disruptive.
Cons: Doesn’t solve cold bridging. May fail again.
- Removing & Replacing with Fascia + uPVC or Aluminium Gutter
Pros: Long-term solution. Improves insulation and appearance.
This is our preferred approach, as it eliminates future damp and thermal issues in one go.
Finlock unit forms lintel – removal must be done with care.
Speak to a Chartered Surveyor Today
If you suspect Finlock gutters may be behind your damp, mould or structural issues, we recommend a professional survey without delay. Replacing them now could save you thousands later.
Call us on 0203 805 1078 or 01622 236500
Why Choose Adkins Consultants?
RICS Surveyors
Chartered Engineers
Local expertise across London Kent and the South East
Experience with Finlock gutters and associated structural issues
Fast, friendly and professional service
