What this work involves
Discuss internal or external insulation and assess the complete build-up, including junctions at walls and roof windows.
- Internal or external approach
- Junctions and vapour behaviour
- Internal finishes and ventilation
Use the following design considerations when coordinating this service with a wider project. Agree which parts apply to your request.
Assess frame, reveal, insulation and internal finish as one junction.
What the drawing needs to explain
Place existing and proposed elevations side by side and add a window-opening section. Mark visible changes and elements requiring adaptation inside.
Allow for later maintenance
Keep a record of the differences between existing and renewed details. Include product information and locations of components that must remain accessible.
Which trade-off matters?
New performance and existing proportions need assessment together. A different frame profile can affect glass area, reveals and internal finishes; compare the complete detail, not just the product rating.
Cost factors for this service
Costs depend on roof shape, access, build-up and reinstatement. Ask for the scope and selected specification to be described separately.
Bring this to the discussion
Photographs of the existing situation, available drawings and your requirements for roof insulation. Identify the elements that should remain.
Questions about the work
What should I discuss before arranging roof insulation?
Thickness alone is not enough. Performance also depends on material, junctions and the existing roof assembly.
The design situations here illustrate choices; they are not completed projects or a diagnosis of your property.

