How to glue concrete


Concrete is an important and equally popular building material. In addition to the classic mechanical processing techniques, you can also glue concrete. Depending on your requirements, you can use different techniques and products when bonding concrete.

One of the most important building materials

Concrete is an essential building material. Even skyscrapers and skyscrapers could not be built at these heights without concrete. This is how concrete is used in numerous ways:

  • supporting components and walls in the outdoor area
  • supporting components and walls in the interior
  • Floors (from concrete screed to prestressed concrete floor to exposed concrete floor)
  • Walls inside and out
  • Floor and path plates
  • Stand (umbrella etc.)
  • Vessels such as flowerpots etc.

The varied processing of concrete

Concrete can be processed in a variety of ways. You can mill concrete or sand the concrete smoothly. You can also waterproof or shape it. Depending on how you use concrete, you can glue concrete differently. First of all, you have to distinguish what exactly should be glued:

  • Floor slabs (concrete and / or on concrete foundation)
  • glue and seal (against water)
  • Cladding and other materials on concrete walls
  • Heavy duty dowels and fasteners (threads, rods) holes drilled in concrete

Properties when bonding concrete

This list could be extended endlessly. Another distinction may be made according to the properties associated with gluing:

  • sticking at points or over the entire surface
  • required adhesive force (calculated in kilograms per square meter)
  • Concrete with concrete or concrete with other materials
  • indoors or outdoors
  • water repellent or impermeable to water

Various adhesives for use with concrete

After all these specifications then different adhesives can be used. Even the adhesives that you can use for bonding to or from concrete are no less diverse:

  • Concrete as an adhesive for floor slabs (concrete or mortar bed outdoors)
  • Tile adhesive as adhesive for floor tiles (flexible tile adhesive indoors)
  • chemical adhesives based on polymers (numerous properties, also over the entire surface or selectively)

Mortar or concrete as a concrete adhesive

If you use concrete or mortar as an adhesive, for example for floor slabs, you can also differentiate according to different approaches. So you can create a thin or thick bed. In addition, you can use the concrete adhesive fluent or earth-moist. It always depends on the circumstances.

Soil-moist concrete adhesive (mortar, concrete) is suitable if it is to prevent water from penetrating and breaking up plates in the event of frost. If air pockets and the like have to be avoided, it is advisable to use a flowing adhesive in the thin bed. In addition, in such adhesives for concrete (tile adhesive, mortar, etc.), if necessary, the application of a primer, since concrete itself is only slightly absorbent.

Chemical glue for bonding concrete

On the other hand, if you use chemical adhesives, the exact requirements must first be taken into account. You can also use chemical adhesives such as silicone or acrylic to seal parts of the building (rain gutter, balcony, terrace, basement foundations, etc.). When used as a point adhesive, however, it is mostly about the direct adhesive properties:

  • very fast (within seconds) strongly adhesive
  • sticking slowly to be able to repair or adjust differently
  • very high adhesive strength

Consider required bond strength and other important properties

Here, too, there is the right adhesive for concrete for almost every requirement. Depending on the product, the adhesive force ranges from 50 kg / m² and up to 400 kg / m². You must take into account whether adhesive must be distributed over the entire surface, or whether the pulling of beads (with a silicone syringe from the cartridge) is sufficient.

Fix and glue threaded rods, anchors and heavy-duty dowels

Also often done by do-it-yourselfers are threads, heavy-duty dowels or metal bars that need to be glued in concrete or with concrete. For example, when building a canopy or a carport, the (mostly made of wood) stand must be mounted on a metal shoe, which you previously anchored with and / or in the concrete floor. For this you use special metal shoes or threaded rods. These rods push through a crossbar in the lower part. Then the part is set in concrete and works like an anchor.

The right chemical adhesive for concrete for every application

On walls, on the other hand, you can use a chemical adhesive for heavy-duty dowels that not only bonds solidly to the concrete or masonry but also to the metal or that adheres to it. You can use different chemical adhesives and adapt them exactly to your requirements. However, there are also special concrete adhesives for injecting the glue into drilled holes.

Tips & Tricks

A very old trick, which was already used by the Romans and which is still very efficient, is often forgotten: water glass. For example, if you add water glass to the cement for your concrete mix, the concrete adhesive becomes impermeable to water. But you can also drill concrete components and inject water glass. It then closes the capillary pores efficiently against, for example, rising water in the masonry.


Video Board: SAKRETE Construction Adhesive How-To Video