What this work involves
An extra storey changes more than the roof. The existing structure, staircase position, escape arrangements and installation routes need to be considered together. Establish what the building can support before settling the design.
- Existing structure and foundation assessment
- Stair opening and usable room layout
- Roof shape and neighbouring buildings
- Facade materials, windows and insulation
- Lifting, scaffolding and temporary weather protection
Use the following design considerations when coordinating this service with a wider project. Agree which parts apply to your request.
Identify which existing elements an addition needs to prepare now.
Which trade-off matters?
A complete approach can improve coordination, while phased work spreads the budget. Compare which junctions would need reworking after a delay and which elements can be completed independently.
What the drawing needs to explain
Create a phase drawing with three colours: repair now, improve later and investigate first. Mark where phases meet, such as roof edges, service routes and finished floors.
Decide this before construction
Address assessed causes of defects before new finishes conceal them. Plan comfort measures together with ventilation and necessary access to building services.
Cost factors for this service
Include design, investigations, structural work, the new envelope and internal finishes. Additional strengthening can change the budget.
Bring this to the discussion
Existing plans, photographs of roof and facades, intended rooms and information about earlier alterations.
Questions about the work
Is every flat roof suitable for another floor?
No. The building, its foundation and the rules for the property are decisive. Structural assessment and a location-specific permit check belong in the preparation.
The design situations here illustrate choices; they are not completed projects or a diagnosis of your property.

