What are roofing details?

Roofing details refer to the specific components and finishing touches that ensure a roof is both functional and aesthetically pleasing. These details play a crucial role in protecting a building from weather elements while also enhancing its overall design. From the way a roof transitions at joints to the materials used for flashing and edging, every detail contributes to the roof’s durability and performance.

Types of Roofing Details

Flashing Details – Flashing is essential for preventing water infiltration at vulnerable points, such as valleys, chimneys, and roof-to-wall intersections. Properly installed metal or membrane flashing directs water away from these areas, reducing the risk of leaks and damage.

Examples of flashings can be found at interfaces with adjoining buildings or structures.

Areas such as chimney stacks that penetrate a roof slope will need an effective flashing.

Commonly, flashings are installed in lead by leadwork specialists. Importantly, lead flashing details should be fitted in accordance with BS6915 and LSTA Guidelines. Further, reliance on flashings as the sole barrier for areas such as chimney stacks may be short sighted.

Owing to changing weather patters, elements such as chimney stacks may also require an integral lead tray, installed above the flashing to prevent moisture from penetrating behind the flashings which are often only installed circa 25mm into the bricks or masonry facade. Recent weather events have seen traditional masonry chimney stacks as the subject of water ingress despite correct flashings having been installed.

Eave and Verge Details – The eaves (roof overhangs) and verges (edges of the roof) require careful detailing to protect against wind uplift and moisture ingress. Materials like lead, zinc, or specially designed fascias and soffits help maintain a secure and polished finish.

There are a range of traditional and modern methods of forming an eaves detail, products such as plastic eaves trays can offer a cost effective and practical solution to forming an eave. Traditional bedded eaves still have their place on certain types of buildings, but it is crucial that such details are used in context and are properly executed.

A poorly finished eaves detail will degrade quickly, as it is the run off point for all of the rainwater flowing from a roof slope. Incorrect eaves details that do not effectively manage the flow of rainwater into a gutter can cause significant damage to the building fabric and may result in penetrating damp and ingress.

Please note that the following list is not exhaustive, and all roofing details must be understood in context. However, by using specific pages, available via this article, we can explore rowing details in greater detail.

Ridge and Hip Details – The ridge (topmost peak) and hips (angled edges) require durable capping to ensure water resistance and structural integrity.

These can be finished with materials such as clay or concrete ridge tiles, metal cappings, or modern dry-fix systems for long-term durability. Importantly, BS5534 promotes the eradication of mortar bedded hip and ridge details, in place of this lead hips and ridges can be used to provide a maintenance free solution.

This project provides a case study for lead hip and ridge tiles and completely eradicates the use of mortar from the roof.  If a bedded ridge system must be used, the tiles must also be mechanically fixed to comply with BS5534. This will require contractors to drill holes in the ridge tiles and integrate an appropriate mechanical fixing into the ridge tree at the apex of a roof. This can be problematic if using certain types of reclaimed ridge tiles

Gutter and Drainage Details – Properly designed rainwater management systems, including gutters, downpipes, and outlets, prevent water buildup and potential structural damage. Choosing the right material and positioning is key to long-term efficiency. Further, when considering gutter details, it is critical that contractors take into account the changing nature of the UK weather. With heavier, more frequent, and prolonged rainfall, gutters and downpipes must be enlarged to mitigate overflow that may result in damage to the building fabric.

More specific roofing details 

Before considering the nature of specific roofing details, it is first important to reference the core British Standards associated with roofing work.

Every roofing contractor should be aware of, and have access to a copy of, the following standards:

1. BS5534:2014+A2:2018 is the code of practice for slating and tiling for pitched roofs and vertical cladding.
2. BS6915:2001+A1:2014 Is the code of practice for installing rolled lead sheet.
3. BS6229:2018 is the current code of practice for flat roof areas with fully supported flexible coverings. Items such as Sarnafil and other Single ply membranes would fall into this category. Further, areas such as integral gutters may also be covered by the standard to ensure minimum recommended falls are achieved.

Verge details 

Verge details in roofing refer to the finishing at the edges of a roof where it meets the gable end. These details protect the exposed edges from wind uplift, water ingress, and general wear while also providing a clean and aesthetic finish.

Common verge detailing methods include:

• Wet Verge – Uses mortar to secure tiles or slates along the verge, creating a traditional and seamless look. However, it requires maintenance as mortar can crack over time.
• Dry Verge – A modern, maintenance-free system using interlocking plastic or metal caps to cover the verge edge, offering better durability and resistance to weathering.
• Bedded Ridge Tiles or Slate Detailing – For slate or tiled roofs, verges may include mechanically fixed ridge tiles or slate-and-lead detailing for a refined finish.

Further, verge details may also be customised using items such as zinc, stainless steel or lead. Again, the overriding aim is to eradicate the use of mortar and reduce maintenance.

Below is an example of a verge detail which has been formed using timber section and lead. The capping in this instance has two functions.

1. It cloaks the verge and eliminates the need for a mortar bed.
2. It offers protection to the timber barge boards and painted surfaces of the same prolonging maintenance periods.

Coping stone interfaces on roof areas can be particularly problematic.

At GNR, we have very specific ways of addressing these details. Ultimately coping stones can cause penetrating damp into a building, usually via the top of the copings.

The following section provides an overview of how, at GNR, we interface different roof coverings with coping stones.

Without question, one of the most appropriate details for a coping interface is to cap the stones in lead. However, where this is not possible, a lead damp proof course (DPC) should be installed. Alternatively, you can use other materials to act as a damp proof course such as modern membranes and even slates. Importantly if lead is used, it should be done in such a way that a key for the copings and mortar bed underneath can be created.

The series of images relate to different coping details which form part of our daily work.

Coping interface with slate roof, secret gutter detail

Westmorland slates with stone copings onto lead and slate DPC.

where it is not possible to remove the copings, because the stones are too big or they have been designed in such a way to allow water run off, a secret gutter detail can still be used.

Secret gutter detail with slates

New Westmorland slates with stone eaves detail installed without gutter to allow run off onto aisle roof below.