Independent School, Gloucestershire - Felt Roof Overlay

Project Overview

Gloucestershire, generic reference only

£67,239 ex VAT

Service: Roofing

Sector: Education

Approved Contractor: MLG UK Ltd
System Installed: Alumasc Euroroof Premium felt system with PIR insulation
Client: Independent school, Gloucestershire (client not to be named)
Duration: Six weeks, within the summer holiday
Work Carried Out: Felt overlay system, PIR insulation, Layboard detailing, bespoke leadwork

Scope of Work

A felt roof overlay to an independent school building in Gloucestershire. The existing asphalt roof was reaching the end of its serviceable life, not yet leaking, but the client wanted a new system carrying a long-term warranty and a thermal upgrade to future-proof the property. MLG’s first school project in an Alumasc felt system.

Alumasc Euroroof Premium 2-layer felt system with PIR insulation
Overlay adopted rather than strip-out, to avoid exposing an occupied building
Careful preparation of an undulating existing deck to receive the overlay
Layboard detailing to the perimeter slate roof
Bespoke leadwork flashings to adjacent masonry and stonework

Systems installed

Waterproofing: Euroroof Premium two-layer felt system: MLG’s first school project in an Alumasc felt system
Insulation: PIR insulation (Alumasc)

Challenges & Constraints

An occupied building

The building was occupied accommodation, so stripping the roof off and exposing it was not an option.

An undulating deck

The overlay had to be laid over an existing deck that was uneven and had to be prepared rather than replaced.

Hot works in heatwave

The programme ran through a continuous heatwave, with hot works involved throughout.

Project Execution & Techniques

Overlay, not strip-out

An overlay was specified precisely so the occupied building never had to be opened up.

Deck prepared carefully

The existing undulating deck was prepared carefully to receive the new system rather than levelled or torn out.

Junctions detailed individually

Layboard detailing was used at the perimeter slate roof and bespoke leadwork flashings at adjacent masonry and stonework, rather than standard trims.

Alumasc felt over PIR

The Alumasc Euroroof Premium two-layer felt system was installed over PIR insulation, MLG’s first school project in an Alumasc felt system.

Outcome & Long-Term Benefits

A warranted system

The client got a new system carrying a long-term warranty in place of an asphalt roof reaching the end of its serviceable life.

Thermal upgrade

PIR insulation within the overlay gave the building a thermal upgrade at the same time as the waterproofing.

Building never exposed

The work was completed without the occupied accommodation building ever being opened up to the weather.

On time, on budget

The job finished within the agreed timescales and on budget, hot works and heatwave included.

Conclusion

The asphalt roof on this Gloucestershire school building was not leaking, but it was reaching the end of its serviceable life. The client wanted to deal with it before it failed, and wanted a long-term warranty and a thermal upgrade out of the work. The building was occupied accommodation, which ruled out a strip-out.

MLG overlaid it in the Alumasc Euroroof Premium two-layer felt system over PIR insulation, preparing an undulating deck rather than replacing it, and detailing the junctions with the slate roof and the surrounding stonework individually in Layboard and bespoke leadwork. Hot works ran through a sustained heatwave and the job still finished to programme and to budget, at £67,239 ex VAT.