Coleford roofs, specifically
Why roof moss grows so well on high ground in the west Forest.
Coleford is the main town on the western side of the Forest of Dean, sitting up on the plateau between the Forest's woodland and the Wye Valley, a few miles from the Welsh border at Monmouth. That position matters for roofs. Weather coming in from the west reaches Coleford before it reaches the Severn Vale, the town is higher and wetter than Gloucester, and there are trees on almost every side. A roof here spends a lot of the year damp, and moss, lichen and the black streaks of gloeocapsa algae thrive on damp.
The ground around the town adds to it. To the west the land drops steeply towards Newland and Redbrook on the Wye, and the houses down there sit in deep, shaded ground where mist hangs on into the morning. To the south and east, villages like Milkwall, Sling and Coalway run right up to the Forest itself, so many back gardens end at a line of oaks and conifers. North-facing pitches and roofs overhung by trees are always the worst: by the time someone rings us, the moss is often packed thick between the slates and has started filling the gutters.
Coleford's older houses are built from the stone underneath them. The Forest's grey and brown sandstone and the paler limestone around the edge of the coalfield both turn up in the walls of the cottages in the town centre and in the villages, mostly roofed in Welsh slate, with clay tile on some cottages and outbuildings. Many of the small stone cottages in places like Berry Hill, Christchurch and Broadwell started life as cottages put up on the edge of the Forest by miners and quarrymen, so they are often old, low and irregular, with roofs that have been patched over the years.
Around them is a lot of 20th-century housing: post-war estates, plenty of bungalows and dormer bungalows across the villages, and newer homes on the edges of the town. Those are mostly concrete interlocking tile, whose rough surface holds on to spores, so they green up quickly here too. The right method is different for each type of roof, which is why we survey first rather than quoting one price over the phone.