Roofers in ColneRoof Repairs & RepointingFrom a BB8 Base

Property along Colne's ridge takes sustained wind with very little shelter. Air pressure differences across the roof pull upward on ridge tiles and verge caps, and any joint already weakened by age gives way.

The failure is progressive: one tile lifts, the exposed bed washes out, the next tile loosens. A ridge line inspected and repointed in autumn is a straightforward job; the same ridge after a January storm has taken half of it, along with the slates it landed on, is a much larger bill.

Colne sits high enough to get a genuinely cold winter. Water soaks into open mortar joints and stone, freezes, expands and forces the joint wider, then the cycle repeats, sometimes dozens of times in a season.

Chimney flaunching is usually the first casualty, followed by ridge bedding and verge pointing. Once the flaunching has cracked, water runs down inside the stack and reappears as damp on the chimney breast in the bedroom below.

Rain here rarely falls straight down. Driven horizontally, it gets under slate laps, behind poorly dressed flashings and past verge details that would be adequate anywhere more sheltered.

This is why lead detailing matters so much on Colne property. Correctly sized, correctly dressed lead at abutments, back gutters and valleys is the difference between a roof that copes and one that leaks every time the wind turns.

The damp Pennine climate grows moss quickly, particularly on north-facing pitches and roofs shaded by higher neighbouring property. Moss holds water against the covering, blocks gutters as it sheds, and forces water sideways under laps.

It should be scraped off carefully by hand, with the roof inspected as the work goes on. High-pressure washing strips the surface off slates and tiles and can take years off a covering that was otherwise sound.