TB/18 – Verge Detail: Warm Roof

This warm roof verge detail illustrates the junction between an insulated masonry cavity wall and a pitched roof insulated at rafter level.

It is intended for architectural designers, building professionals, contractors, developers and self-builders coordinating roof insulation, gable restraint and weather protection. Use it alongside the matching warm-roof eaves drawing; Approved Document L provides the official energy-efficiency guidance.

The detail shows:

• External brickwork and Celcon Solar aircrete block inner leaf
• Partial-fill cavity-wall insulation and clear residual cavity
• Insulation between and beneath the rafters or trusses
• Insulation continuity between the roof and external wall
• Insulated infill between the final rafter and gable wall
• Insulated cavity closer and fire-resisting cavity barrier
• Gable-wall restraint straps and supporting noggings
• Breathable roofing membrane
• Ventilation above the insulation where required
• Vapour-control and airtightness layer
• Proprietary dry-verge or traditional undercloak construction
• Render termination beneath the verge
• SAP junction reference E13
• Calculated psi value of 0.057 W/m·K

The accompanying notes cover roof structure, gable restraint, insulation installation, ventilation, condensation control, cavity closure, airtightness, mechanical fixing and verge weather protection.

What This Warm Roof Verge Detail Includes

• One downloadable PDF construction drawing
• A3 landscape sheet
• Drawn at 1:10 when printed at 100% on A3 paper
• Drawing reference: TB/18
• Detail title: Verge Detail – Warm Roof

Important Information

This is a standard construction detail intended to provide general guidance. Rafter or truss sizes, bracing, restraint, verge support and fixings must be confirmed through the structural design.

Insulation thickness, ventilation and vapour-control requirements must be coordinated with the approved U-value calculation, roofing-underlay certification and condensation-risk assessment.

The stated psi value applies only where the illustrated construction, geometry and insulation arrangement are followed.

The drawing does not include structural calculations, a roof layout, U-value calculation, condensation-risk analysis, SAP assessment or Building Regulations approval.

The PDF is supplied for use by the purchaser on their own projects. It may not be resold, redistributed or reproduced for commercial resale without written permission.