How to plaster on surface

Plaster is a mixture of sand and cement with water. 1:4 or 1:6 ratio of cement-sand is mixed for making plastering mortar. 1:4 cement-sand mortar is used for plastering masonry surface and 1:6 cement-sand mortar is used for RCC surface plastering. The thickness of plaster on surface is ranging from 12mm to 25mm depending on the surface condition.

Purpose of plastering:
Plaster is used for covering the rough surface of RCC and masonry work to obtain a smooth, even, regular, clean and durable surface and with the object of improving the resistance of the surface to rain water penetration and atmospheric influences.


Construction process of plastering:

Surface preparation-

·        First of all, chip the RCC surface
 
·        Brush and scrap the cured surface to make it free from mortar, oil, greasy spots and efflorescence and loose materials.
 
·        Wash the surface with water and keep it moist before commencing plaster. But no excess water will be on surface and it will be saturated and dry.


Mixing materials-

·        Separate the foreign materials and larger particles from sand with the help of sieve.
 
·        Measure the required quantity of sand and keep them in a dry and plane place.
 
·        Spread the measured cement on sand
 
·        Mix the dry volume of cement & sand until the mixture is uniform. Then add water gradually till the mix is plastic.
 
Application of plaster-

·        Apply cement grout on RCC surface.
 
·        Make 75mm x 75mm patch of plaster @ 2 – 3 m c/c as reference level of plaster.
 
·        Apply the mortar on surface.
 
·        Check the level of the surface with thread and spirit level. Check should be made for each 5 square meter of finished surface area. If the surface is not level then redo the area by scratching when the mortar is still green.
 
·        Finish the surface with wooden trowel, broom and wetted foam. Wetted foam is used to prevent water percolation from cement mortar.
 
·        Cure the finished plastered surface after 24 hours with water continuously for at least 14 days.

Important notes to care -

·        Do not apply dry cement-sand mix on the prepared surface.
 
·        The mortar should be used within 1 hour after mixing adding water with cement-sand mix.
 
·        Add water proofing agent 0.25% by weight of cement for plastering of basement wall, reservoir and water retaining wall. For outside plastering of building add water proofing agent 0.50% by weight of cement.

Please reply:
- How do you mix cement mortar?
- What tools do you use for plastering?

1 comments :

  1. To plaster a brick wall with cement is very necessary for decoration of your home. Without plaster, your brick wall will not shine. But due to increasing labor cost, it has become costly.

    ReplyDelete

 

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