Solution For Plaster Debonding For Old Construction (Renovation)

Solution for Plaster Debonding for old construction(Renovation)

Debonding in newly constructed plastered surface occurs when plaster is separated from the wall. It can be caused by an excessively thick plaster layer, inadequate substrate preparation, carks in the base of the concrete or masonry or may be due to a dusty, oily, or dry substrate.
In older structures there can also be a variety of reasons due to which plaster is de-bonded. Over roof concrete surfaces, plaster is usually deboned due to the moisture ingress and corrosion of the reinforcement, this causes the plaster to be de-bonded. Furthermore, with regular usage of the structure and general wear and tear plaster de-bonding occurs. To repair the de-bonded surface, there are a few protocols that can be followed which can extend the life of the structure and provide relief.


There are a few basic steps which can be followed to repair the deboned plaster for(Renovation).

Summary of application

Step 1: Removal of all old, deformed plaster and cleaning the area.
Step 2: Assessment of area and repairing.
Step 3: Re-plastering using 3 different options.
A. Patch 365 Plus
B. Adding Ressi SBR 5850 and Silmix in the Plaster Mix.

Step 1: Removal of all old, deformed plaster and cleaning the area.

Prior to any repair work it is essential to clean the area of all the loose plaster. Once old, deformed works have been cleaned, there should be a thorough assessment of the area to make sure that there the right treatment for the problems is implemented.

Step 2: Assessment of area and repairing.

in old, constructed structures there are a variety of spaces where plaster debonding occurs. If the plaster and concrete cover over the roof has been de-bonded and there is exposed steel, it is recommended to make sure that remedial steps are taken to make sure further internal deterioration does not occur. If there is water ingress from the top of the surface that should be addressed by waterproofing the roof slab with Water Guard 3020N or Waterproofing Membrane and proper roof assessment. Please refer to the system for the rectification of leaked roof.

Furthermore, for internal surface it is recommended to remove the rust from the reinforcement as much as possible, it is also recommended to apply a metal mesh over the affected surface prior to the application of Patch 365 Plus or a mortar made from Ressi SBR 5850 and Silmix. 

If there are minor hairline cracks over the walls, they too can be rectified using Crack Heal 920 2K. If the cracks are 6mm or wider, they too can be Crack Heal 920 2K. Please refer to the product technical datasheets for further information on the products and their usage

Step 3: Replastering of the surface.

Once proper assessment is done and the base problems have been addressed, it is essential to replaster. 

Using Patch 365 Plus: If there is a movement within the structure or a plaster with added flexibility and water resistance capabilities is required, Patch 365 Plus is an ideal product for that. Patch 365 Plus is a two-component dry premix repairing mortar useful for the repairing of old deformed plaster works, damaged floor screed with potholes and concrete where surface honeycombing has occurred. Please refer to the product technical datasheet for further information.

Adding Ressi SBR 5850 and   Silmix in the plaster Mix: A plaster comprising of a good ratio can also be applied over the wall area. It is recommended to add Ressi SBR 5850 and Silmix into the plaster mix. The recommended dosage of Ressi SBR 5850  and Silmix is 1 Ltr each to be added with the mix of every 50 KG bag of cement. Once the plaster has been applied and cured properly. Subsequent treatment can be done over the wall

Application Animation

Solution For Plaster Debonding For Old Construction (Renovation)