Substrate Preparation For Liquid Applied Waterproofing - Icopal

Substrate Preparation

Before applying roof coatings ensure that surfaces to be coated are firmly fixed, smooth and free from any contaminants that could inhibit adhesion.

Generally when cleaning, scrape and sweep away bulk of contamination then clean any remaining contamination by suitable means e.g. power washing, grit blasting or mechanical abrading. Use approved detergents for more effective washing and to remove oil and grease.

Organic growth can be treated using an approved fungicidal wash. All preliminary work including formation of up-stands, kerbs, box gutters, sumps, grooves, chases, expansion joints, etc. and fixing of battens, fillets, anchoring plugs/strips, etc. should be complete and satisfactory.

Substrate Surface Preparation Primer
Bituminous Membranes

Cut back cracked and defective areas of felt as required, star cut blisters, dry out and re-bond.

Check integrity of upstands and cut back or repair. Any splits wider than 3mm should be filled prior to the application of the system. Enviroflex can be used for filling such voids.

Dry Concrete

New concrete based surfaces should be fully cured and over 28 days old.

Surfaces should be free from friable material, laitance or any contamination to allow suitable adhesion of the waterproofing system.

Uneven concrete with peaks or voids greater than 10mm can either be levelled with an approved material or mechanically prepared to give a smoother finish.

Any repairs over 15mm thickness should be built up in layers.

Investigate any structural defects or cracks in the substrate before applying the waterproofing system.


Wet Concrete

Synthetic Membranes (PVC/EPDM)

Sand surface and clean surface (e.g. Ethyl Acetate or MEK based cleaning solution) prior to appling primer. Adhesion test is recommended.


Allow suitable gaps between boards to allow for expansion or contraction.

Joints in sheets should be taped with Sealoflex Foil Jointing Tape to prevent loss of Enduroflex coating between the boards.

All boards must be securely fixed in accordance with the sheeting manufacturers specification and all areas must be swept to remove dust and debris, which could cause the system to de-bond.

Any damaged boards should be replaced (Note: OSB type 3 tends to be less porous and hence requires less primer).

Metal (Zn, Al etc.)

Inspect, remove and replace structurally unsound sheets.

Metal surfaces should be cleaned with white spirit.

Powder coated metal should be test for suitable adhesion.

Improved adhesion may be achieved by lightly abrading the surface before cleaning with white spirit.

Any corrosion or oxidation should be removed by wire brushing or mechanical abrading. To prevent future re0oxidation of the brushed metal, apply Enduroflex directly to the unprimed surface.




Ceramic / Tiles



A qualitative adhesion pull test procedure should be performed prior to any project where adhesion may be questionable.

Typical drying time for Enduroflex Primers:

Depending upon atmospheric conditions, curing time can vary: 

  • for Enduroflex EP1 primer, from 30 minutes (at 23 °C / 50 % RH) to 1h30 (at 10°C / 50%RH). The white primer cures to a translucent finish when completely dry.
  • for Enduroflex Acrylic Primer, from 1h (at 23 °C / 50 % RH) to 3h30 (at 10°C / 50%RH). The blue primer cures to a darker blue colour when completely dry. 




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    Icopal Liquid Applied Waterproofing Systems