Optimax PRO PV

The substrate should be even and stable. The moisture content of the board substrate should not exceed 21%.

The product should not raise any objections. The roll should be evenly rolled, without kinks.

If it is necessary to make the covering at low ambient temperatures, it is recommended to store the rolls in heated rooms for 24 hours before installation. At ambient temperatures below 10°C, it is recommended to heat the self-adhesive overlap using, for example, a hot air gun.

During acceptance, the following should be checked:
- correctness of bonding of overlaps with particular attention to transverse overlaps,
- correctness of mechanical fastening and securing of visible fasteners,
- correctness of detail work.

Secure the NEXLER Optimax PRO PV bituminous membrane to the wooden substrate with roofing nails or staples that are at least 140/10 in size.
Roofing nails or staples should be driven perpendicular to the substrate to ensure maximum tightness of the joints. Mechanical fastening should be carried out to a depth of at least ¾ of the roof decking thickness.

Fixing methods:

• only under the membrane overlap - in this case, it is necessary to simultaneously attach counter battens or the final covering made of standing seam metal roofing or bitumen shingles. Fasten under the overlap with nails or roofing staples at a minimum spacing of 26 cm in two lines.
• under the overlap with nails or roofing staples every 13 cm in two lines, and additionally through the overlap with nails approximately every 20 cm alternately in two lines - in this case, installation of counter-battens and/or the final covering can be carried out at a later stage of the work.

The fixing patterns are shown in the product's Technical Data Sheet.

Installation recommendations:

• on roofs with a slope up to 50%, the membrane should be laid parallel to the eaves, while for slopes greater than 50%, it should be laid perpendicular,
• overlap width 12 cm.

Longitudinal overlaps do not require extra adhesive - after removing the protective film from the strips, the bitumen bonds with the bitumen, creating a durable joint.
Transverse overlaps must be sealed with a bituminous adhesive, such as NEXLER Arbolex Aqua Stop, NEXLER Adhesive for Bituminous Felt and Shingles or NEXLER Bitumen Roofing Sealant.
Additional sealing is required for the membrane starter strip and all vertical flashings.
At low temperatures, before installing counter battens, we recommend sealing the membrane surface under the puncture points using the above-mentioned bituminous compounds.

Additional sealing of overlaps and mechanically fastened areas should be performed in the following cases:

• mechanical installation through the overlap,
• installation at ambient temperatures below +10°C (or activation with a hot air gun),
• on roofs with a slope of less than 20%, the longitudinal overlap with the self-adhesive strip requires longer contact time or additional sealing and pressing to ensure immediate and effective bonding.

In areas of the roof exposed to prolonged contact with rainwater, e.g. gutter hopper heads, gutter flashings, roof edges, vertical chimney flashings, etc. the membrane should be applied in two layers.

Before use, please read the application details in the product's Technical Data Sheet.