Chapter one
Friday Street's stone, slate and tile side by side
A street where each century repaired the last gives roofs of different thickness, weight and age meeting along shared lines.
Friday Street shows what a Weald village looks like when each century repairs the last. The council's 2020 appraisal records roofs there that run from traditional Horsham Stone slates, through slate on the Victorian houses, to clay roof tiles. Warnham's ground is Weald clay broken by outcrops of Horsham Stone, so the stone is a local product, laid on local roofs for a very long time. Beside it, the slate and the tile tell us when each house was built or rebuilt, and each covering has its own way of letting go. Handmade clay tiles from different periods vary in colour too, so we hold replacements against the old before choosing. They also age differently on the surface: the appraisal for Horsham town says stone can appear to coalesce as it weathers, slate stays smooth, and tile gathers moss in shade. A roof's face can therefore mislead about its condition, which is why we lift and look beneath.
At a glance
- Friday Street mixes stone, slate and clay tile
- Different thicknesses make the joins the weak points
- Shadow slates weather the joints on some stone roofs
1.1 Where one covering ends and the next begins
Neighbouring roofs in different coverings are never the same thickness. Stone slabs are thick, slate is thin, and clay tile sits somewhere between, so the line where one roof meets another needs flashing cut to suit both. We check these joins, along with the valleys and abutments around them, before we turn to the main slopes, because a gap there lets water straight down into a wall head or a ceiling void. A valley between a stone slope and a tiled one is especially awkward, since the lead has to bridge a change in thickness and sit tight to both. A single storm can expose the weakest join on a whole street.
1.2 Mixed laps and shadow slates
Horsham District Council's appraisal of Horsham town describes stone roofs repaired over time as a blend of double-lap and single-lap work, with shadow slates covering for missing stone. Shadow slates are small pieces of Welsh slate bedded in mortar to weather the joints between stone slabs. The same patchwork turns up on repaired roofs elsewhere in the Weald, and it tells us how earlier hands coped with shortages. When we reach one, we identify what each section is, photograph it, and repair it in the same method instead of forcing a uniform pattern. Advice from the Stone Roofing Association is that double lap slating should be retained or reinstated wherever possible. Our Horsham stone roofing page covers the detail, and your quote is written once the survey has shown which method each part of the roof was laid in.
Three Friday Street coverings and how long they last
| Covering | Typical life, as published |
|---|---|
| Horsham Stone slates | No fixed figure; depends on the stone, the timbers and upkeep |
| Natural slate | Properly installed, quoted at 80 to 100 years or more |
| Clay roof tiles | Marley cites a minimum life expectancy of 60 years; old peg-tile roofs are harder to predict |
