Waterproofing and final layer
Within the PolyShield system shown, the white UV-resistant membrane immediately forms the waterproof final layer. There is therefore no need for a separate fifth protective finishing layer. Primer, detail treatment and membrane must be assessed as one system.
The layer is applied continuously over the prepared roof surface and around suitable connections. Seams, bilges, drains and penetrations are given the detail required by their movement and shape in advance.
Sun reflection and roof temperature
A light roof surface generally absorbs less solar radiation than a dark surface. As a result, the surface temperature can be lower on sunny days. The actual effect varies per building, insulation level, ventilation and use.
A white roof should therefore not automatically be sold as an energy-saving measure with a fixed percentage. If energy saving is a project goal, the effect should be calculated separately.
Surface and preparation
White does not make flaws less important. Loose layers, contamination, moisture and inadequate repairs remain risks for adhesion and durability. The surface must be cleaned, repaired and tested where necessary.
The choice of primer depends on the existing roof covering, porosity, moisture condition and any old coatings. Combining products without written technical approval does not fit within a controlled approach.
- Clean the surface and let it dry
- Perform a test bond where necessary
- Dealing with details before the main plane
- Monitor consumption and layer thickness during implementation
Pollution and maintenance
Dust, algae, leaves and atmospheric pollution can reduce white appearance and reflection. Dirt can collect especially around drains, installations and areas with little slope.
Periodic inspection focuses on drains, damage, connections and contamination. Cleaning must match the membrane; Aggressive agents or hard mechanical loads can cause damage.
When a white membrane fits
A white system can be interesting for larger commercial roofs with a lot of sunlight, a maintenance task and a technically suitable existing structure.
The color is ultimately one property. Waterproofing, adhesion, detailing and maintainability continue to determine the quality of the roof.
This explanation is general and does not constitute project-specific system advice. Subsurface investigation, tax and official system documentation remain decisive.