Walk any street of thirty-year-old houses and you'll spot the pattern: cracked mortar lines under the ridge tiles, gaps at the gable edges, grey chunks in gardens after windy nights. That's mortar bedding reaching the end of one of its short lives — and dry ridge and dry verge are the industry's answer to never having that conversation again.
Why mortar fails up there
Mortar is rigid; roofs aren't. Tiles expand and contract daily, timbers flex, and the ridge and verge take the most exposed weather on the building. Every movement opens hairline cracks, every winter's freeze-thaw prises them wider, and eventually the bedding lets go — typically 25–40 years per application, less in exposure. Re-bedding restores it, on the same clock, forever.
What "dry" fixing means
Dry ridge fixes every ridge tile mechanically — screws into the ridge timber, clamps between tiles, and a ventilated roll sealing the junction underneath. Nothing to crack, every tile positively held against wind, and useful loft ventilation thrown in (a genuine help against condensation). Dry verge does the same at the gable edges: interlocking caps screwed over each end tile, sealing the edge against rain, wind-lift and birds. Both have been standard on new builds for years — retrofit brings older roofs up to the same detail.
Is conversion worth it?
If your mortar has already failed, usually yes: a proper re-bed and a dry-fix conversion cost broadly similar money, but you pay for dry-fix once. The honest exceptions: conservation contexts where the mortar detail is required or the look matters, and roofs whose tiles don't suit the available systems — both things a survey settles in minutes. What's never worth it is the drive-by special: fresh mortar smeared over the old bedding, which peels off in sheets within a couple of winters.