Karnak 19 Ultra

The revolutionary new 'Rubberised Flashing Cement'



Permanent, underwater repairs now available to the UK market…

The Product:
Karnak #19 Ultra rubberised flashing cement is the next generation in emergency waterproofing solutions. Scientifically compounded with a selection of rubber reinforced asphalt, mineral fibres and refined solvents. #19 Ultra is a heavy, pliable consistency for easy application by trowel. #19 Ultra contains special chemical ingredients which give it unique water displacement qualities for permanent underwater repairs. #19 Ultra dries to a tough, flexible, waterproof and corrosion proof rubber coating which gives maximum protection and performance over a wide range of temperature and weather conditions.

Surface Preparation:

All surfaces should be clean and free from grease, oil, dust, dirt, loose paint and other foreign matter. Remove excess water where possible. If this isn’t possible don’t worry, #19 Ultra can be applied and will fully cure underwater!


Spread Karnak #19 Ultra Flashing Cement to an average thickness of 3-4mm and press tightly into joints, seams or cracks.
Embed Karnak Reinforcement Membrane into the #19 Ultra.
Apply an additional coat of Karnak #19 Ultra over the entire patch, again at 3-4mm.
Your patch repair is now complete
Can be applied for a permanent repair even UNDERWATER!
Karnak #19 Ultra Key Benefits
Excellent adhesion on:
  • Wet or Dry application
  • Adheres underwater, first time, every time
  • Rubberised – Elastomeric
  • Superior water and weather resistance
  • Will not shrink or crack
  • Smooth, rubber-like consistency
  • Excellent adhesion
  • UV stable
  • Easy and ready to apply, no mixing required
  • Permanent underwater repairs
  • Excellent ‘sag’ resistance for use on vertical surfaces
  • Quick curing
  • Bitumen
  • Felt
  • Shingles
  • Tiles
  • Metal
  • Asphalt
  • Downpipes
  • Vertical walls
  • Chimneys
  • Flues
  • Skylight flashings
And much more...


Karnak kit includes 

 1 x 3.40 Litre tin

 7m Mesh

2 x Spreaders

2 Pair of Latex Gloves

Photography for illustrative purposes only. 
For more information on the Karak 19# Ultra please give us a call on 01452 713 400 or email sales@the-roof-shop.co.uk 



Display per page
Sort by

Karnak 19 Ultra 0.25L Cartridge

£8.27 *
In stock
can be shipped within 2 - 5 days

Karnak 45m x 150mm Reinforcement Tape

£20.48 *
In stock
can be shipped within 2 - 5 days

Karna-Flex 3.4L Kit

£95.88 *
In stock
can be shipped within 2 - 5 days
* Prices without VAT or delivery