1. The Danger of London Weather
When undertaking a complete Full Refurbishment involving mansard extensions or total structural rebuilds in the London Borough of Hammersmith & Fulham (LBHF), the existing historic slate roof is entirely stripped away. This leaves the un-waterproofed interior violently exposed to heavy London rainfall for several months.
2. The inadequacy of Blue Tarps
Inexperienced developers often attempt to protect the open structure using vast sheets of blue plastic heavy-duty tarpaulin tied over the scaffolding. In a severe winter storm, these tarps sheer, rip, or blow away entirely. The resulting catastrophic water ingress can destroy newly laid oak floors, cause historic lath-and-plaster ceilings to collapse, and flood the newly excavated basement.
3. The "Tin Hat" Solution
Hampstead Renovations mandates the installation of a "Temporary Roof" (industry slang: a Tin Hat) for all major roof-off structural projects. This is a massive, highly engineered, freestanding corrugated metal roof structure literally built entirely over the existing house, supported by heavy-duty external scaffolding.
4. Planning Permission for Scaffolding?
While standard scaffolding does not typically require planning permission, a massive temporary roof structure that towers ten feet above the existing ridgeline and remains in place for 12 months frequently triggers complaints from Conservation Area neighbors claiming loss of light or visual dominance. We must carefully liaise with the Planning Directorate and highways to ensure the scaffolding licenses cover the true scale of the temporal structure.
5. The Financial Calculation
A corrugated tin hat is wildly expensive, often costing tens of thousands of pounds just to rent for a year. However, it guarantees the site remains 100% bone dry. This allows our craftsmen to lay high-end interior finishes on the ground floor while the roof is still missing above them, shaving months off the project schedule and preventing catastrophic water damage insurance claims.
How We Can Help
If you are considering a major refurbishment, extension or basement in Hammersmith & Fulham, our in-house architectural and construction teams are highly experienced with the specific constraints and policies of LBHF. Do not leave your planning application to chance—our Planning & Permissions and Architecture services are explicitly designed to handle strict London authorities from initial conceptual design through to final, legal consent.
Once permission is secured, our Refurbishment & Interiors division carefully manages the execution, guaranteeing the design integrity is maintained throughout the build phase.
*Published in the Hampstead Renovations Planning Guide Collection — delivering expert design and build strategies for London's most heavily guarded conservation boroughs.*