Waterproofing torch-on membrane.

Unigum® and Fidia P are waterproofing membranes made of polymer modified bitumen which have been reinforced with a rot proof fabric and a strengthened fibreglass mat, therefore has excellent stability to different temperatures. The top face is covered with fine talc and the bottom face is embossed and lined with anti-adhesive film. Mineral versions are also produced on which the top face has slate granules.

Unigum® gets mostly used in hotter climates and Fidia in cooler climates.

Whereas the VIS P is a waterproofing membrane made of polymer modified bitumen which is stabilized with a rot proof fabric / fibreglass composite reinforcing. Ideal for use in warmer climates.

abe construction chemicals DIY fidia p unigum visp applications


for Unigum 

  • For renovation purposes.

Suitable for solving the most difficult waterproofing problems on:

  • flat roofs.
  • sloping and pitched roofs.
  • reinforced concrete.
  • prefabricated concrete.
  • masonry cement.
  • metal and timber decks and terraces, with or without thermal insulation.

for Fidia P

Use either in a single layer or in conjunction with other layers as a base sheet for:

  • continuous waterproofing.
  • foundations.
  • tunnels.
  • tanks.
  • parapets.

for VIS P

Ideal as single or multi-layer waterproofing systems for new building work or for refurbishment:

  • on all sloping surfaces (on fl at, vertical and curved surfaces).
  • on different types of substrates (prefabricated concrete substrates, timber roofing, most thermal insulation).

For roof waterproofing 

  • Under layer or intermediate layer.

For damp proofing

  • Basement tanking.
  • Foundations.
  • High elongation strength.
  • Extreme temperature resistance.
  • Long life expectancy.
  • Guaranteed water tight.
  • Recyclable.
  • Stable.
  • Shear resistance of joints.
  • Resistance to tearing.
  • Puncture resistant.

abe construction chemicals DIY fidia p unigum visp properties


abe Construction Chemicals - fidia p unigum visp - colour

Bonding / Priming

All cementitious surfaces must be primed with abe® bitu.®prime at a rate of approximately 3.5 m2/L.  Depending on the porosity of the surface a second coat of primer may be required.


Depending on the different construction types, the sheets must be fully bonded to the substrate.  See Index publications ‘Technical Specifications’ or ‘Application manual’ which also describe other methods of application such as mechanical fixing, hot air welding and bonding with adhesives. The substrate must be clean, dry, smooth and free of roughness or dips. The cast concrete surface must be allowed to dry before the sheet is applied.  Drying depends on the weather and may take from 8 days to 3 weeks.  To protect timber floors from the flame, either sheets of ROLLBASE or abe® malthoid 5-ply must be nailed before application of the membrane.  

Torch-bonding is carried out with a suitable gas torch burner connected to a propane gas cylinder.  To bond the sheet to the substrate and on the overlaps, use the torch flame to melt the flaming lining on the lower face of the membrane while the membrane is being unrolled.  The sheets are overlapped longitudinally by 100 mm, while the head laps of the polyester reinforced membrane should not be less than 150 mm.

Bonding is carried out by torch application in such a way that a continuous bead of melted bitumen comes out from the overlap.  So as not to remove the protective top layer, the use of a trowel is to be avoided.

When overlaying mineral finished membranes, the mineral surface must be heated so that the slate granules are completely embedded in the overlap.  

The correct temperature for bonding the membrane on the substrate and the overlaps is indicated when the protective flaming burns off. However the membrane must not be overheated and a further sign of correct application is that an excessively large bead of melted compound does not come out from the overlap.


Effective coverage: 8.9 m 2/roll.


Tools, brushes and mixing equipment should be cleaned immediately after use and before material has set with abe® super brush cleaner followed by washing with soap and water.

Protection on Completion

Waterproofing torch-on membrane should be allowed to weather for a minimum of 8 – 10 weeks before overcoating with 2 coats of abe® silvakote. The system should dry for 7 – 10 days and then overcoat exposed area with abe® silvakote.


Supplied in rolls of 10 m x 1 m.


This is not a do-it-yourself product, consult an experienced contractor.

Health & Safety

Product safety information required for safe use is not included.  Before handling, read product and safety data sheets and container labels for safe use, physical and health hazard information.  The safety data sheet is available from your local a.b.e.® Construction Chemicals branch.