Following the passing of our good friend and mentor Heinz Jahn, Cathedral Stone Products, Inc. in the USA purchased and maintains the sole ownership rights to the Jahn products and intellectual property.

Therefore, for any enquiries relating to the Jahn M and Jahn S ranges, please visit Cathedral Stone

Jahn M90 Concrete Repair Mortar is a mineral-based, single-component mortar that was developed for the curative and preventative repair of concrete. M90 meets the requirements of the CUR-recommendation 54 – Concrete Repair with manually applied or poured cement-based mortars.

Available in a variety of grades and in a range of standard and custom colours, M90 is suitable for repairing concrete constructions such as bridges, viaducts, tunnels, industrial constructions and houses.

M90 is supplied ready to mix with water and contains no acrylic or latex bonding agents or additives. Being vapour permeable protects the substrate by allowing salts, vapour and water to reach the surface preventing failure due to salt expansion or freeze thaw cycles.

By providing a healthy pH factor with a strong resistance to carbonation, M90 does not allow corrosion to begin. The mortar is able to withstand severe environmental conditions and is not damaged when heavy concentrations of salt crystallisation are present.

As well as Coarse and Fine grades, M90 Concrete Retouch is also available.

M90 Concrete Retouch was developed in the lab to create a product that could be applied as a very thin (2mm) and taught coat to provide a very smooth surface. Besides the mechanical repair of concrete, Retouch is also suitable for fixing and compensating for uneven surfaces and detail differences, thus upgrading the original character of the concrete.
In addition to these advantages, the M90 Concrete Retouch also prevents deterioration by natural and anthropogenic emissions, such as CO2 and acidification by acid rain.

The repair of concrete.

  • Engineered in the lab, proven in the field
  • Single component mixes with water only
  • Highly moisture, frost and salt resistant and salt and moisture regulating
  • Vapour permeable – prevents failure due to salt expansion or freeze/thaw cycles.
  • Highly resistant to carbonation
  • Single layer build-up – faster and more economical
  • Non-shrinking
  • Scientifically controlled – no on-site chemistry resulting in product variation
  • Can be manually or mechanically applied.
  • Strong adhesion – requires no bonding agent
  • Water Based: Environmentally and user safe – no solvent clean up or disposal problems

Trade Enquiries

Please call to discuss your requirements. Discounts are available for bulk orders and for Steadfast Registered Installers.

Same Day Dispatch

If you order before 10am on any week day we will endeavour to dispatch your items on the same day via your chosen shipping option. Please note that this may not be possible for larger items.

Customer Support

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