Ambient air temperature

+10 °C min. / +40 °C max.

Substrate temperature

+10 °C min. / +40 °C max.

Substrate moisture content

< 6 %

SUBSTRATE QUALITY

SYSTEM DESIGN

Consider the following when designing the waterproofing system:

• The supporting structure must be of sufficient structural strength to support all new and existing layers of the roof build-up.

• The complete roof system must be designed to withstand and be secured against wind uplift loadings.

• The wind uplift resistance of the adhered roofing assembly is limited by the adhesion strength of the product to the substrate.

SUBSTRATE CONDITION

The substrate surface must be uniform, firm, smooth and free of any sharp protrusion or burrs, clean, dry, free of grease, laitance, oil, dust and loosely adhering particles.

SUBSTRATE PREPARATION

PREPARATION

New concrete should be cured for at least 28 days and should have a pull off strength ≥ 1.5 N/mm². Cementitious or mineral based substrates must be prepared mechanically to remove cement laitance and to achieve an open textured surface. Loose friable material and weak concrete must be completely removed and surface defects such as blowholes and voids must be fully exposed. The concrete must be carefully assessed for moisture content, air entrapment, and surface finish prior to any primer application.

PRIMING

Primer selection

Note: For information on selecting the appropriate primer, contact Sika Technical Service.

1. Apply the appropriate SikaShield® primer with the required consumption onto the prepared dry surface.
   Note: Refer to the individual Product Data Sheet of the primer.
2. Allow the primer to dry before membrane installation.

APPLICATION

IMPORTANT

Unrolling at low temperatures

At low temperatures, the membrane becomes less flexible.

1. Be careful when unrolling to avoid damaging the membrane.

IMPORTANT

Damage through footwear

Footwear with spikes or sharp protrusions may puncture the membrane.

1. Use footwear with a flat profile when walking over the membrane.

IMPORTANT

Damage through overheating

The polyester reinforcement melts at +260 °C. If it is damaged through overheating, the membrane becomes unusable.

1. Keep moving the flame while torching to avoid overheating the membrane.

IMPORTANT

Reduced adhesion through insufficient heating

Make sure to heat the membrane sufficiently. If it is not sufficiently heated, the adhesion to the substrate, between layers or on the overlaps will be reduced.

1. If the membrane does not adhere to other elements, lift and re-torch the unbonded areas.

Tackiness at high temperatures

Note: When laying the membrane at high temperatures, the integral adhesive will become ‘tacky’ and may restrict laying operations.

ALIGNMENT

IMPORTANT

Avoid coinciding joints

To avoid coinciding joints, lay the membranes parallel to one another with staggering. When applying on another bituminous membrane, make sure to stagger the overlaps of the previous layer.

1. Unroll the membrane.
2. Align the membrane.
3. Re-roll the membrane before application.

MEMBRANE OVERLAPS

1. Overlap the membranes by a minimum of 80-100 mm on the sides and 150 mm on each end.
2. At the end overlap, cut off a corner measuring 80-100 mm per side at an angle of 45°.
3. Weld the overlaps with great care until you see a trickle of melted mixture about 10 mm wide coming out along the line of the overlap.

TORCHING

1. Heat the substrate and the backing film on the underside of the membrane with a gas burner.
2. When the backing film starts to melt, the membrane is ready to stick.
3. Roll the heated membrane forward and press it firmly against the substrate to bond it.
4. Make sure a bead of melted bitumen is visible along the full length of the overlap sides and ends when laying.

Suitable substrates for torching

• Concrete

• Bituminous membranes with a smooth surface

• Coatings (check the compatibility)

• Plastered brick / block masonry

• Cementitious screeds

DETAILING

1. Use a sharp knife to cut in all details such as internal and external corners, upstands, vent pipes, drains, support metalwork etc.

Refer to the relevant method statement for further information on detailing.