Applications
Add fire protection
or combine it with reroofing?
When reroofing, plan SHEET beneath the new membrane. If the existing membrane stays, consider VLOEI mineral roof coating or WEER exterior boards. Access, added load and drainage determine the installation.
01 · Applications
New roof or new membrane
On a new build or a complete membrane replacement, the roof build-up is open. A mineral protection and load-spreading board such as VlamShield SHEET can then be installed between the insulation and new membrane. It provides a flat substrate for waterproofing. The added weight is included in the structural calculation, and board installation is coordinated with the waterproofing work.
What matters
- Choose membrane and insulation that are assessed together with the cover board as a system
- Include the added weight of the board in the structural calculation
- Plan staggered joints for insulation, board and membrane
- Work out roof edges and penetrations as separate details
02 · Applications
Existing waterproofing stays
If the roof membrane is intact, a mineral protective layer above it can avoid removing the waterproofing. WEER is an option as water-resistant exterior boards. VLOEI is a cement-bound mineral roof coating with reaction-to-fire class A1, applied to a prepared substrate and cured on site. For boards, consider support on the membrane and wind restraint; for roof coatings, adhesion and application temperature. The area beneath existing PV modules must be accessible, so partial dismantling may be necessary.
What matters
- Adhesion test on the roof before the quotation becomes final
- Record the condition of seams, upstands and outlets
- Account for weather conditions and seasons: temperature, moisture and rain
- Detail terminations at support feet and upstands separately
03 · Applications
Mineral boards on the roof surface beneath PV
On PVC-P, granule-surfaced bitumen, PIB or TPO/FPO, WEER is an option as water-resistant boards directly beneath the PV installation. The membrane continues to provide waterproofing, while outlets and maintenance points remain accessible.
What matters
- Record the exact membrane product and its condition
- Assign contact compatibility and any intermediate layer
- Plan weight per unit area and wind restraint together
- Preserve drainage and maintenance access
Applications
Where things go wrong: seams, outlets, upstands
The protective layer must work across the roof and at interruptions. Mark joints, outlets and upstands on the layout before ordering.
- 01
Seams and joints
Joint staggering follows the selected roofing system. Movement joints must retain their function. Membrane laps and transitions need separate detailing when applying a mineral roof coating.
- 02
Outlets and emergency overflows
Every layer stops short of outlets and overflows. No intervention may reduce drainage; the check is part of handover.
- 03
Upstands and roof edges
Fixing and drainage change at upstands. Design the board termination, membrane junction and inspection access together. Any penetration through the waterproofing needs a suitable sealed detail.
Which protective layer suits your roof?
