THE LEAD LADS® / PROJECT ARCHIVE
A complete Code 5 lead dormer covering in Bakewell, formed with seven wood-roll roof bays, welted lead cheeks, bespoke edge restraint and a dedicated ventilation route above the insulation layer.
BAKEWELL · DERBYSHIRE · CODE 5 LEAD · VENTED ROOF BUILD-UP · LEAD DORMER
Explore the Project01 — THE PROJECT
This Bakewell project involved the complete lead covering of a newly formed rear dormer as part of a loft conversion.
The dormer interrupts the existing Welsh slate roof and introduces several different weathering zones: the principal roof covering, vertical cheeks, front apron, leading edge, side drips and junctions with the surrounding slate.
Its construction also required a deliberate ventilation strategy. Restricted space towards the apex led to purpose-made Nicholson roof vents being incorporated to maintain the specified airflow route above the insulation layer.
The finished dormer therefore combines traditional sheet-lead detailing with a project-specific approach to ventilation, movement and exposed-edge restraint.
LOCATION
PROGRAMME
LEAD CODE
ROOF LAYOUT
02 — THE DORMER
A dormer is not simply a small flat roof sitting within a pitched roof.
It introduces horizontal and vertical surfaces, exposed leading edges, side junctions and transitions back into the main roof covering.
On this project, the leadwork therefore had to be considered as one complete assembly rather than as separate roof, cheek and apron details.
03 — THE BUILD-UP
The moisture strategy for a dormer depends on the complete construction beneath the external covering.
On this particular project, the specified arrangement incorporated a ventilated void above the insulation.
Restricted space at the upper junction meant that purpose-made Nicholson roof vents were used to maintain airflow through the build-up where a more conventional opening would have been difficult to achieve.
This ventilation strategy is separate from the movement requirements of the sheet lead itself. The lead covering still requires suitable bay dimensions, joints, support and restraint regardless of the thermal construction beneath it.
A different dormer build-up may require a different condensation-control strategy, so the arrangement used here should be understood as project-specific rather than a universal dormer detail.
The new structure before completion of the full external lead weathering system.
Wood rolls divide the roof into individual Code 5 sheets and establish the finished roof geometry.
Roof, cheeks, apron, drips and leading edge operating as one coordinated lead envelope.
04 — VENTILATION
The project incorporated a defined ventilated zone above the insulation.
The challenge was maintaining that route where the dormer construction approached the restricted upper junction beneath the main roof.
Purpose-made Nicholson vents provided a solution at this interface, allowing the specified ventilation route to continue without compromising the external lead covering.
The important principle is not simply to add vents to a lead roof. It is to preserve the moisture-control strategy intended for the particular roof build-up.
05 — WIND + RESTRAINT
Dormers create prominent edges above the main roof plane.
On this project, the leading edge incorporated a purpose-made stainless-steel restraint detail to create a consistent line and secure the lead covering.
The side drips were also lapped over the cheeks and tabbed as part of the project-specific approach to the exposed perimeter.
These restraint details complement the sheet layout above: the lead still needs freedom to move within the bay arrangement while vulnerable edges are appropriately controlled.
06 — SIGNATURE DETAIL
The defining visual feature of the finished dormer is the repeated rhythm of the roof bays.
Seven individual Code 5 sheets are separated by traditional wood-roll joints across the width of the dormer.
The rolls do more than create an architectural pattern. They divide the overall roof into individual pieces, establishing a controlled sheet layout through which movement can be accommodated.
The result is a roof whose technical organisation remains clearly visible in its finished form.
07 — SUPPORT + VENTILATION
08 — LEADWORK INSTALLATION
09 — MATERIALS
CODE 5 LEAD →
WOOD ROLLS →
LEAD UNDERLAY →
LEADWORK FIXINGS →
LEAD SIZING + ORDERING →
10 — THE CRAFT
A lead dormer brings several different sheet-lead techniques together within a small area. The quality of the finished work depends on those details being designed as parts of one envelope rather than completed independently.
11 — PROJECT RECORD
The Bakewell image record follows the dormer from the prepared structure through formation of the seven-bay lead roof and into the finished cheeks, apron and perimeter details.
It provides a particularly useful example of how the external lead covering and the construction strategy beneath it need to be resolved together without confusing their separate functions.
12 — LEAD DORMERS
A lead dormer combines several fundamentally different details within a compact envelope.
The roof sheets need suitable support and movement allowance. The cheeks must shed water vertically while remaining secure. The apron must transition back into the main roof covering. Exposed edges require appropriate restraint.
That is why a dormer should be designed as one integrated weathering system rather than a series of unrelated flashings.
Lead Dormers →
Lead Dormer Windows Guide →
Leadwork Guides →
13 — VENTILATED CONSTRUCTION
Ventilation and lead-sheet movement solve different technical problems.
On this dormer, the roof construction was arranged with a ventilated void above the insulation and the upper junction was detailed to preserve that air route.
The lead sheets above still required suitable bay dimensions, fully supported substrates, joints and fixings.
On another dormer, the thermal and moisture design may be different. Ventilation should therefore follow the intended roof build-up rather than being added automatically because the outer covering happens to be lead.
14 — WHAT THIS PROJECT SHOWS
The most useful lesson from the Bakewell dormer lies beneath the finished metalwork.
A visually successful lead dormer still depends on what happens below the sheet: the support, insulation strategy, moisture control, ventilation route and geometry of the substrate.
Above that build-up, the lead has its own requirements for sheet division, movement, fixing and edge restraint.
The completed dormer works because those different technical layers were coordinated rather than treated as the same problem.
PROJECT TAKEAWAYS
15 — FREQUENTLY ASKED
Code 5 rolled lead sheet was used for the roof covering and cheek cladding on this Bakewell project. The appropriate lead code for another dormer depends on the individual detail, sheet dimensions and specification.
The bay arrangement divides the overall roof into individual sheets and provides a controlled way of accommodating movement through the roof layout.
Wood rolls create the raised longitudinal joints between adjoining lead sheets and form part of the traditional sheet layout used on this roof.
No. The moisture-control strategy depends on the complete construction. This project was specifically designed with a ventilated zone above the insulation, so the ventilation route formed an important part of the dormer build-up.
The restricted geometry at the upper junction required a practical way of maintaining the specified ventilation path within the available space.
Yes. On this project the cheeks were covered using welted Code 5 lead panels secured with appropriate cleats and fixings.
A purpose-made stainless-steel restraint was formed for this project to create a consistent and secure leading-edge detail.
16 — MATERIALS + RESOURCES
Lead Roofing Project Archive →
Lead Dormers →
Lead Dormer Windows Guide →
Leadwork Guides →
Leadwork Standards →
Code 5 Rolled Lead →
Wood Rolls →
Lead Underlay →
Leadwork Fixings →
Lead Sizing + Ordering Chart →
THE LEAD LADS® / PROJECT ARCHIVE
The Bakewell dormer forms part of The Lead Lads® project archive documenting traditional sheet-lead detailing across dormers, bays, flat roofs, gutters, canopies, heritage buildings and specialist architectural work.
Its defining feature is the relationship between the visible leadwork and the construction beneath it: seven Code 5 roof bays, welted cheeks, carefully restrained edges and a ventilation path designed specifically around the dormer build-up.
