Concrete blocks and Cinder Blocks have many pores on their surface. The size of the pores is more significant when compared with the pores on the normal concrete surface. Cinder blocks are permeable to vapour and also water. A concrete block sealer is applied on the surface of the concrete blocks to reduce the porosity. The sealer keeps the cover of the concrete blocks dry and also prevents water leakage. Most of the best quality concrete block sealer prevent leakage or cracks and reduce the degree of efflorescence and mould by keeping the concrete block dry. By applying sealer on the surface of the concrete block, they are easy to clean and maintain.

A solvent-based sealer is best for concrete blocks and cinder blocks. Solvent-based sealers will penetrate the concrete block’s surface, and their durability will be extended compared with the other types of sealers. In the retail shop, the concrete block sealer is available and can be used directly. It suggested applying at least two coats on the surface of the concrete blocks, and before applying the sealer on the concrete block, wet the whole surface. You can use a spray method for applying a solvent-based sealer, and for the usual type, you can apply directly with a brush or roller. 

The water-based sealer can be used for the cinder or concrete blocks that do not have any issues related to moisture. The water-based sealer will prevent the entering of water from ground level. It also reduces the development of mould efflorescence. The water-based sealer can be easily cleaned. A water-based concrete block sealer is available in a concentrated ultra-version. 

Before applying to the concrete block, the ultra-concentrated sealer should be mixed with distilled water. It is recommended to add four gallons of water with the ultra-concentrated sealer. The process of applying is a little different from the standard sealer type. Like a typical sealer, two coatings should be applied on the concrete or cinder blocks, but the second coating should be applied before the first coating is dried. The water-based sealer should be applied to the wet wall only. The concrete block sealer will not affect the natural property or colour of the concrete blocks even when they are exposed to heavy UV light rays. 

Method for applying sealer on concrete blocks:

  1. First, you need to dry the concrete blocks before applying the sealer. So drill a hole in the bottom and leave it to dry for two to three days. 
  2. Remove all the mould, efflorescence, mildew, and other related things from the concrete block’s surface.
  3. After cleaning the surface, apply the sealer on the concrete blocks using the spray method or regular brush. Give at least three sealer coatings on the concrete block surface after each layer leaves the wall free to dry for half an hour to one hour. Proper ventilation is required while applying the sealer on the surface of the concrete blocks.
  4. After applying a sealer, you can add decorative things to the surface of the wall.