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    ​​​​​​Solutions for Rain Damaged Concrete Surfaces

    When concrete is pumped or finished in the rain, the after effects can often lead to a series of failures which can cause structures to become weakened and even dangerous over time.​ 

    Failures Caused by Rain Damaged Slabs:


    If rain falls on a slab during the initial set, it is common that the surface layer of cement will be removed, exposing the aggregate, leaving an unappealing final result (shown below).​
    ​​ is a polymer modified fairing mortar which develops high early and ultimate strengths. MasterEmaco N 5100 is chloride-free, shrinkage compensated and supplied ready-to-use.

    Concrete Spalling ​

    If the rain is relentless, steel reinforcement may also become exposed, leading to concrete spalling from the expanding, oxidized steel.​

    Solution: Break out the concrete to the effected areas and if active corrosion is present, treat with MasterProtect 8500CI. Then, prime with MasterEmaco P 5000AP, and apply a MasterEmaco S 5300CI or MasterEmaco S 5400CI​, depending on the time required to return to the asset to service.

    The high build structural repair mortar has active corrosion inhibition, which not only hinders ongoing internal corrosion, but will also help to protect the surface concrete from external corrosive forces.

    Rain damaged surfaces are complex to repair and it’s important to know what shortcoming is causing the defect prior to starting repair works. 

    Before you begin repairs, we recommend that you speak to the Master Builders Solutions Team so that we can offer sound engineering advice, conduct testing of the concrete and help you select the right product to eliminate any chance of further failures.
    Contact the team on 1300 227 300 or enquire at: