Dry Ridge vs Mortar Ridge: Which Roofing System Is Right for Your Home?
Posted by John Price May 29th, 2026
The ridge of your roof — that horizontal line running along the very top — does far more than complete the look of your home. It is one of the most weather-exposed parts of the structure, taking the full force of wind, rain, and temperature fluctuations year-round. How those ridge tiles are fixed in place makes a genuine difference to the longevity and safety of your roof.
For decades, ridge tiles were bedded in mortar. Today, dry ridge systems have become the standard for new and re-roofed homes across the UK. If you are planning roof work, understanding the difference between the two will help you make a confident, informed decision.
What Is a Mortar Ridge System?
A mortar ridge is the traditional method. Ridge tiles are bedded in a sand-and-cement mix, which hardens to hold them in place and seal the joint at the apex of the roof. For generations, this was simply how roofs were finished, and a well-executed mortar ridge can look beautiful — particularly on older and period properties where the soft, settled appearance of mortar suits the character of the building.
The drawback is that mortar is a rigid material sitting on top of a structure that naturally moves. Roofs expand, contract and flex slightly with changing temperatures and wind loads. Over time, this movement causes mortar to crack, crumble and work loose.
Once that happens, water can creep in, tiles can slip, and in high winds, a loose ridge tile can become a serious hazard. Most mortar ridges need attention — repointing or rebedding — within 10 to 15 years.
What Is a Dry Ridge System?
A dry ridge system eliminates mortar entirely. Instead, ridge tiles are secured using mechanical fixings — screws and clamps — that anchor each tile firmly to the roof. A ventilated ridge roll membrane runs beneath the tiles, sealing against driving rain while still allowing air to pass through.
Because the components are designed to flex with the building rather than against it, a dry ridge system holds firm where mortar would crack. A correctly installed dry ridge can last as long as the roof itself — often 50 years or more — with virtually no maintenance.
The Key Technical Differences
The two systems differ in three fundamental ways:
- Fixing method: Mortar relies on adhesion and weight to hold tiles down. A dry ridge relies on mechanical screws and clamps, which do not degrade with weathering.
- Movement tolerance: Rigid mortar cracks under structural movement. Dry ridge components accommodate it.
- Weatherproofing: Mortar seals the joint only while it remains intact. A dry ridge uses a purpose-made waterproof union that channels rain away while remaining permanently flexible.
The Advantages of Dry Ridge Systems
Built-in ventilation
One of the most valuable benefits of a dry ridge is ventilation. The ridge roll allows warm, moist air to escape from the roof space at the highest point, helping to prevent the condensation that leads to damp, mould and rotting timbers. Mortar, by contrast, seals the ridge completely, trapping moisture inside the loft. Good ventilation protects both your roof structure and your home’s health.
Superior storm and wind resistance
This is where dry ridge systems really prove their worth. Because each tile is mechanically anchored rather than simply bedded down, dry ridges stay put in severe weather. As the UK experiences more frequent and more intense storms, this resilience matters more than ever. Mechanically fixed ridges are far less likely to lift, slip or be torn away during high winds.
Low maintenance and long life
With no mortar to crack or repoint, a dry ridge needs little to no upkeep over its lifetime. That means fewer call-outs, fewer repairs and lower long-term costs, even though the initial installation may carry a modest premium over traditional mortar.
Why British Standards Now Require Dry Fixing
This shift is not just a matter of preference — it reflects a change in the rules. The relevant British Standard, BS 5534 (the code of practice for slating and tiling), was substantially revised in 2014 and came into force for all new roofing contracts from 28 February 2015.
The revised standard made clear that mortar alone can no longer be relied upon to secure roof coverings. All ridge, hip and verge tiles must now be mechanically fixed — even where mortar is still used, it must be accompanied by a mechanical fixing. The change was driven by an increase in extreme weather and the need for roofs that remain secure under higher wind loads.
A further amendment in 2018 introduced BS 8612, which sets the quality and performance requirements that dry-fix ridge, hip and verge products must meet to be considered compliant. In practice, the most straightforward way to meet these standards is to use a proprietary dry ridge system. For any new build or re-roof, dry fixing is now the norm.
What About Heritage Buildings?
There is an important exception. BS 5534 itself acknowledges that its recommendations may not be appropriate for heritage roofs, where traditional fixing methods can conflict with the standard. On listed buildings and properties in conservation areas, the soft, authentic appearance of a mortar ridge — or the use of reclaimed ridge tiles — is often essential to preserving the building’s character.
In these cases, the right approach is to consult your local planning authority and a conservation specialist so a suitable, sympathetic solution can be agreed. Heritage and compliance are not always in conflict, but they do call for expert judgment.
Which Should You Choose? A Buyer’s Guide
For most homeowners, the decision is straightforward:
- Building a new home or re-roofing? A dry ridge system is the clear choice. It is required for compliance with BS 5534, offers superior weather resistance and ventilation, and is virtually maintenance-free.
- Worried about ongoing upkeep? Dry Ridge wins comfortably. The higher upfront cost is repaid many times over in saved repairs.
- Living in an exposed or storm-prone location? Mechanical fixing offers peace of mind that mortar simply cannot match.
- Own a listed or period property? Speak to a conservation expert. A mortar finish may be the most appropriate — and sometimes the only permitted — option, but it will still need mechanical fixing to comply.
The Final Decision
A dry ridge system delivers better ventilation, stronger storm resistance, far less maintenance and full compliance with current British Standards. For the vast majority of UK homes, it is the smartest investment for a secure, long-lasting roof.
Mortar still has its place on heritage buildings, where character matters — but for everyday roofing, dry fixing has rightly become the standard.
If you are unsure which system suits your property, our team is here to help. Get in touch for honest, expert advice and a no-obligation quote.
John Price, the owner of JP Roofing Services, is an experienced roofing expert with deep roots in Nottinghamshire. Leading a family-owned business, John has built a reputation for excellence in the local roofing industry. JP Roofing Services offers a comprehensive range of services, including new roof installations, repairs, and maintenance, with specialisations in flat roofs, guttering, fascias, soffits, and chimney work. John’s commitment to reliability, punctuality, and affordable pricing without compromising on quality has made JP Roofing Services a trusted name in the community. With a focus on safety and customer satisfaction, John ensures that every project meets the highest standards, combining traditional values with modern expertise.
