Dry-fix systems hold ridge, hip and verge tiles in place with screws, clips and purpose-made fittings instead of relying on mortar. They need far less upkeep, don't crack or wash out, and usually cope better with strong wind. Mortar can still be used, but under the current British Standard, ridge and hip tiles must also be mechanically fixed, not held by mortar alone. On period homes and in conservation areas, mortar may be the better choice for looks.
What ridges and verges are
- Ridge: the line of tiles along the top of the roof where two slopes meet.
- Hip: the sloping ridge where two roof slopes meet at an outside corner.
- Verge: the edge of the roof at a gable end, where the tiles finish above the wall.
These are the most exposed parts of a roof. They take the strongest wind and the most weather, so they are often the first parts to fail.
Why mortar fails
Traditionally, ridge and hip tiles were bedded on sand and cement mortar, and verges were finished with a strip of mortar along the gable. Mortar is not a glue. It holds tiles mainly by weight and grip, and over time:
- frost and rain wear it away
- the roof timbers move slightly with the seasons, cracking the mortar
- moss and lichen loosen it
- cracked mortar lets water in under the ridge
Once mortar cracks, ridge tiles can rock and lift off in a storm, and lumps of mortar can fall from verges. Repointing or re-bedding helps, but the problem tends to come back.
How dry-fix systems work
Dry ridge and hip
A timber batten is fixed along the top of the roof on metal brackets. A flexible roll is laid over it and sealed onto the tiles on both sides. Each ridge or hip tile is then screwed or clipped to the batten, with sealed joints between tiles. Many dry ridge systems also let air out of the roof space, which can help reduce condensation in the loft.
Dry verge
Dry verge systems use interlocking caps or clipped units that fit over the end of each row of tiles at the gable, fixed to the battens. They replace the strip of mortar entirely. Some systems instead use a neat timber or fixed trim. On plain tile and slate roofs, verge tiles can also be clipped and nailed with a discreet finish.
What the standards say
The British Standard for slating and tiling, BS 5534, was revised in 2014. It requires tiles to be mechanically fixed rather than held by their own weight, with extra fixings at the edges of the roof, and it says mortar alone cannot be used to fix ridge and hip tiles. Mortar can still be used, but the tiles must also be fixed mechanically, for example with screws or clips into a batten.
A separate standard, BS 8612, was published in 2018 for dry-fix ridge, hip and verge products. It tests how well they resist wind, shed water and cope with weathering. Choosing a product that meets BS 8612 is a good way to avoid poor-quality kits.
Dry-fix vs mortar: pros and cons
Dry-fix
- Pros: little maintenance, no cracking or falling mortar, secure in strong wind, can be fitted in most weather, can add ventilation.
- Cons: the plastic verge caps are visible and not to everyone's taste; quality varies between products; may not suit listed homes or conservation areas.
Mortar (with mechanical fixing)
- Pros: traditional appearance, suits period homes, can be matched to the colour of existing work.
- Cons: needs repointing or re-bedding over time, can't be laid in frost or heavy rain, still needs mechanical fixings to meet the standard.
Can dry-fix be added to an existing roof?
Usually, yes. When ridge or verge mortar has failed, the old ridge tiles can often be lifted, cleaned and refitted on a dry ridge system, and dry verges can be fitted along the gable. It depends on the tile type and the condition of the roof, which a roofer will check.
Planning and permissions
Replacing a ridge or verge is a repair and doesn't normally need building regulations approval. But dry verge caps change how the gable looks. If your home is listed, you are likely to need listed building consent, and in a conservation area a visible change like this may need permission. Check with your local council first. Our guide to roofing in a conservation area or on a listed building explains more.
In Essex, Hertfordshire and Cambridgeshire
Dry-fix systems are especially useful on exposed roofs, and these are common across the three counties.
- The coast: In Clacton-on-Sea and on West Mersea, strong winds and salt air lift ridge and hip tiles, loosen verges and break down old mortar faster than inland. Dry-fix ridge and verge systems stand up much better to coastal weather.
- The fens: With flat fenland on every side, Littleport roofs catch the wind, and storms lift ridge tiles and verges. Around Soham, old mortar on ridges and chimneys breaks down over time.
- Open countryside: On the edges of Great Dunmow, storms lift ridge tiles, loosen verges and break down older mortar.
- Newer homes: In Cambourne, loose or cracked mortar on ridges and verges is one of the most common jobs, and a dry-fix ridge and verge system stops it coming back.
- Old clay tile towns: In places with many listed buildings, such as Thaxted, traditional mortar-bedded ridges with matching clay tiles may be the right choice.
How First4Roofcare can help
We fit dry-fix ridge, hip and verge systems, and re-bed and mechanically fix traditional ridges where that suits the house better. See our roof repairs and tiled roofs services, or book a free survey to find out which is right for your roof.