Joints
Thermal protection also depends on how board joints are executed in the actual assembly.
VlamShield SHEET · Cement-bound glass-fibre board beneath roof waterproofing
Thin glass-fibre sheet.
Beneath the new membrane.
SHEET combines a cement-bound matrix with glass-fibre reinforcement in a factory-cured board. Positioned between insulation and new waterproofing, it combines mineral protection with load spreading. The board has a nominal thickness of 10 mm and a mass of 10 kg/m².
01 · Function
Function and installed position
SHEET adds a layer directly above the thermal insulation. The membrane above provides waterproofing; the mineral board beneath forms an additional protective and load-spreading layer.
Loads from PV supports and maintenance must suit insulation compressive performance, board support and joints.
Schematic positions, not an installation drawing. WEER and VLOEI show alternative material routes above the membrane; SHEET sits below it. The illustrated layers are not automatically combined.
What loads act here?
Heat from a PV fire
A thin mineral layer can contribute little fuel yet still transmit heat. Protecting the insulation depends on the temperature profile and the complete assembly.
Point loads and joints
Load spreading depends on the selected board’s stiffness, support areas, joints and insulation compression. The roof’s spare structural load capacity requires a separate assessment.
Moisture before waterproofing
Dry storage, sequencing and protection of open roof areas remain necessary. A layer below a new membrane is different from an exposed roof surface.
02 · Material
Material build-up
The material principle combines a hydraulically hardening cement matrix with alkali-resistant glass-fibre reinforcement. This allows a mineral layer to be placed as a coherent element beneath the new roof membrane.
- Cement-bound matrix from the VLOEI material family
- Fine mineral aggregates to adjust structure and workability
- Alkali-resistant glass-fibre carrier for cohesion and crack control
- Factory curing as the principle of the board format
03 · Installation
Installation on the roof
- 01
Select the assembly
The roof membrane, insulation and requirements for the mineral layer form the starting point. Thickness, format and surface mass are assigned to the specific project proposal.
- 02
Coordinate the board concept
The factory-cured fibre composite is intended for dry laying. Support, handling and cutting follow the selected version.
- 03
Plan joints and fixing
Board joints, edge connections and wind restraint are coordinated with the roof assembly. These details belong in the installation plan.
- 04
Install new waterproofing
The new membrane provides protection against weather and water. Connections and outlets are designed consistently as part of the waterproofing.
Joints, outlets and upstands
Outlets
Thickness and cut pieces must not obstruct drainage. The membrane remains the continuous water-carrying layer.
PV mounts
The protective board does not replace the load-bearing structure. Load spreading, insulation and PV supports must be assessed together.
04 · Data
Material and application
Material and application
An overview of the product line. The specific version and supporting technical documents are assigned in the project proposal.
| Material principle | Cement-bound fibre composite |
|---|---|
| Reinforcement | Alkali-resistant glass-fibre carrier |
| Position | Beneath new roof waterproofing |
| Selection criteria | Build-up height, surface mass, joints and heat transfer |
| Project information | Insulation, roof membrane, PV arrangement and protection requirement |
SHEET compared
Limit the flames.
Account for the heat.
VlamShield SHEET and AllShield BarrierSheet form mineral intermediate layers below new waterproofing. VlamShield SHEET is described here as a 10 mm protective and load-spreading board. Compare the specific configuration and complete roof build-up.
Stopping flames does not stop all heat.
ZAG reports limited fire spread in AS-1, alongside local melting of the full 100 mm EPS thickness due to heat transfer. Acting as a flame barrier and protecting the insulation beneath are two different performances.
ZAG · AS-1, conclusions ↗Two thin layers in the tested assembly.
The roof assembly tested by Efectis uses two thin protective layers: 2.5 mm AllShield BarrierSheet above and below 140 mm PIR. Both layers in their respective positions form part of this tested assembly.
Efectis · R000982, section 3.3 ↗Thickness needs a like-for-like comparison.
Greater thickness increases the steady-state thermal resistance at the same thermal conductivity. When comparing different materials, heat storage, moisture, joints and behaviour under fire exposure also matter. A stiffer cover board can also offer benefits for load distribution and installation.
Compare the complete version: material, position, joints, additional loads and installation. Our technical article explains the published tests and the differences between material families.
Sources for the material comparison
05 · Selection
When yes, when no
Suitable
- New roof waterproofing with a mineral intermediate layer
- Projects with limited build-up height
- Load spreading and mineral protection in a single element
- Project-specific selection of material and roof assembly
Not suitable
- As standalone roof waterproofing
- As a load-bearing board without the relevant structural evidence
- As a replacement for thermal insulation
- Permanently exposed use without an appropriate material specification
06 · Questions
Questions from practice
What is SHEET for?
SHEET forms a mineral protective and load-spreading layer above insulation and below new waterproofing. The board has a nominal thickness of 10 mm and a mass of 10 kg/m². System load capacity depends particularly on insulation, support and joints.
Is SHEET the same as BarrierSheet?
SHEET is VlamShield’s cement-bound approach. BarrierSheet is a separate product line from AllShield. For selection, we compare the specific version, layer position and supporting documentation.
How does SHEET spread loads?
SHEET forms a mineral load-spreading layer on the insulation. Load capacity depends on board stiffness, support areas, joints and the compressive behaviour of the insulation.
What information does an enquiry need?
Send the area, roof assembly, proposed waterproofing, PV arrangement and programme. We compare the material options and specify the appropriate version in the project proposal.
Project enquiry for VlamShield SHEET
Your roof. The right material solution.
Send the roof build-up, area and programme. We compare the sensible options and specify the right version for your project.
Project enquiry- Roof assembly, insulation and proposed new membrane
- Available build-up height and allowable additional roof load
- Area, project location and intended installation date
- PV mounts, access routes and junction details
- Required material and roof-assembly evidence
