Imperma 100 is a deeply-penetrating water repellent fluid for bricks, stones, and concrete. Due to its fluid-based formulation, it is able to penetrate more deeply into its target than standard liquid-applied water seal products.

The fluid is based on proven silane/siloxane technology, and works by lining the pores of the brick rather than blocking them, allowing the wall to ‘breathe’. This is in contrast to many standard brick and stone sealer products that coat the brick with a thin film, preventing it from breathing.

The Imperma 100 fluid is easy to apply using a brush or roller, and only a single coat application is required - many competing water repellent products require two coats.

10 -Year Durability

Imperma 100 is the only colourless brick water-repellent treatment that carries GCA approval. After extensive testing to determine continued water-repellency after aggressive freeze-thaw and UV exposure, GCA issued a certificate with the following durability statement:

“The product will remain effective as a brick water repellent for 10 years.”


By providing in-depth protection against moisture ingress, Imperma 100 is able to save energy. Tests carried out by the University of Portsmouth demonstrate that energy savings of up to 29% are possible by keeping walls dry using Imperma 100. This is because dry walls are better insulators than wet walls.

Flood Protection

Used in conjunction with Imperma 100 Repointing Additive No. 2Imperma 100 is able to increase the flood resistance of the brick without altering its appearance.

Preparation and Application

Imperma 100 should only be applied to dry, porous surfaces. It should not be applied over sealed or painted surfaces and is intended for aboveground use only. It must only be applied when rain has not been forecast for the 24 hours that follow application.

For the treatment to be successful, it is essential to check all joint and roof connections. Hairline cracks up to 0.3mm can be ‘bridged’ by Imperma 100 - however, it may be necessary to fill cracks in brick/stonework and repoint using a suitable sand/lime or sand/cement mortar incorporating Imperma 100 Repointing Additive. Dirty surfaces should be cleaned before the application of Imperma 100. While cleaning of natural stones, brick, terracotta and concrete,” detergents must not be used. Application to structures containing high levels of salt should be avoided.

Test Area

Imperma 100 has been formulated to be colourless once cured. However, very slight darkening may occur when it is applied to some substrates. Although this usually fades over time, a small, representative, and inconspicuous test area should always be treated before full treatment begins. Paints could be applied six hours after application of Imperma 100.

Learn more and place your order

To find out more about Imperma 100 and place your order, please contact us.

Benefits of using Imperma 100

  • Thorough waterproofing and protection
  • Single-coat application
  • Limits biological growths
  • Saves up to 29% on energy bills
  • Usable on a variety of substrates
  • GCA-approved; 10-year durability

Cutting building costs by up to 40%

By making good use of new low-energy consumption technologies and reliable, cost-effective building materials (and the exclusion of cement mortar, plaster, and paint, due to the nature of our Eco Bricks), we're able to cut building costs considerably to save you money.