Joints of paved and slabbed surfaces have frequently become defective after many years of use. Non-bonded jointing material was sweeped or vacuumed out, and open joints remain, which are not only unsightly and badly walkable but also endanger the solid bond of the paved surface. There is the risk of stones to come loose, that leave accident-prone danger spots. Simple resanding can not resp. can only achieve short-term improvement.

Unsuited hydraulically-bound mortars or, especially, polymer-bound mortars show shoulder separations, macroscopic cracks and crumble-offs, causing finally the same already mentioned consequences. The adhesive bond is insufficient, due to deficient joint-preparation, and, furthermore, processing defects are the rule rather than the exception. Besides, there is the risk of disfigurement of the paved or slabbed surface with a film of reaction-resin, which, later on, absorbs and binds the street impurities. Moreover, as a result of frequent small-area repairs and reworks, an inhomogeneously-looking patchwork-rug arises, that does not in the slightest meet the requirements on a natural-stone surface.

To avoid further damages, in parts inner-city useful areas are un-loaded, which causes additional traffic problems, because these streets and squares can not be used as originally designed. STEIN TEC® has, in co-operation with a specialist jointing firm, addressed itself to that problems and has developed a patented joint-repair method (patent number DE 198 48 437 C2) on the basis of many years of experience and respective experiments.

Defective jointing

Defective jointing due to unsuited jointing mortar.


Uncovering of defective joints with a specially designed high-pressure cleaner.


Surface after joint uncovering.

Problem solving

The problem of joint repair has already been gone about by STEIN TEC® many years ago and durably solved. The essential part of the patented technology (DE 198 48 437 C2) are the specially designed STEIN TEC® repair mortar SF 02 – 1K, which has been approved for more than 20 years now, and a specially designed high-pressure cleaner, with which it succeeds to uncover damaged joints in the complete area sufficient-deeply and to clean them for optimal (shoulder) adhesion of the repair jointing. Surface elements, showing defects or damage, will be replaced by specialised personnel as a craftsmen supplementary work. Stones, that have come loose of the bond, will be hammer set with specialty mortar at the appropriate height. Remains of the old mortar will be chipped or milled off, if necessary, and professionally disposed.

After the uncovering of the joints, the joint opening will be sealed with STEIN TEC® Repair Mortar SF 02 – 1 K, and the surface will be cleaned accurately. The special properties of this specialty mortar guarantee excellent solidity and shoulder adhesion. The use of the renovated area is possible within a very short time, due to the mortars quick development of firmness. Special attention should be paid to the paving-block or slab bedding. For surfaces used by vehicles, it shall be executed with appropriate water-permeable mortar and still be intact. In this case, a repair is generally noncritical. If the bedding consists of chippings or chipping/sand mixtures, the exposure time of these areas should be 3 to 5 years, at least. Only then, it can be assumed that the bedding is compressed as far as possible and no compression set will occur anymore. Otherwise, there is the risk of crack formation in the joints. But the stability of the joints will be much bigger after than before the joint repair.

We would be pleased to inform you, on request, of references. The area of the first successful large scale experiment has been in use since 1993 now, therefore the product has a long-term experience of > approx. 20 years. For the execution of the performance, trained personnel should be deployed, only.

If you should have a problem case, please contact us. We would be pleased to give you personal advice and to work out a special proposal for solution.

Grouting process

Grouting process of the efficient-deeply uncovered joints with Joint Repair Mortar SF 02 – 1K.


Cleaning of the grouted surface.


Surface after joint repair.