Lime Plaster: Application, Benefits & Disadvantages
Lime plaster is a type of plaster that is made from marble dust, water, and non-hydraulic hydrated lime, which is also called slaked lime, high calcium lime, or air lime. Plasters made with ancient lime often included horse hair for reinforcement and pozzolanic chemicals to speed up the process.
Lime plaster is created when lime is utilized as a binding agent in mortar for plastering. A mixture of lime and marble dust in equal amounts in a mortar mill is combined with water to form a paste of the desired consistency.
Lime plaster has different amounts of marble dust that control things like shrinkage, strength, porosity, and stickiness. Fine marble dust is best for making lime plaster.
Note: While lime plaster and venetian plaster are similar, there are some key differences.
How Do You Use Lime Plaster?
- Applying more than one lime plaster coat is best. Before you add the second coat, the mortar is spread on the wall in a layer 6–10 mm thick with a trowel to give it a good grip.
- The first coat is followed by the second coat after 24 hour dry time.
- The mortar is pushed and rubbed along the straight edge of the board in the second layer, then leveled with a float to finish evenly.
- After two days, add the third coat, known as the finishing coat, over the second coat; the thickness of the third coat should be at most 3mm.
- The third coat is finished using a metal float to apply a cream of white known as neeru.
Note: If you’re using Venetian plaster, the process is a bit different.
Sand should not be too fine; at most, have only 5% pass through a 100 mesh sieve or 20% pass through a 50 mesh sieve.
To make the plaster more efficient and lasting, the sand should be graded and free of impurities such as stones, trash, grits, muck, etc.
Thick lime or poor lime is often preferred for plastering operations because of the slow, tedious process of hydraulic lime.
For external plastering, cement is occasionally used with lime mortar to increase its strength and characteristics.
There are also different lime plaster mixtures that can be made according to the required texture. Make sure to keep that in consideration based on your desired result.
Here are the top 5 benefits of using lime plaster:
- Lime plaster hardens into a long-lasting solid mass yet still has some degree of flexibility.
- It is porous; therefore, it allows for the movement of moisture and the evaporation of that moisture.
- It is not as susceptible to the effects of water and will not dry out or dissolve in the same way as clay or gypsum mineral plaster.
- Plasters composed of hydrated lime are less brittle and less likely to crack; therefore there is no need for expansion joints in a structure that uses these plasters.
- Lime’s high pH functions as a fungicide, killing any mold that could try to colonize the lime plasters.
- Hydraulic lime plaster is softer than cement plaster in the beginning.
- As the plaster dries, the pH dips to around 8.6.
- Non-hydraulic lime plaster can only dry for a few days since it needs moisture to set.
Here’s a quick “how to” plaster application guide:
- To apply over smooth drywall, apply one coat of Meoded Quartz Primer to make the wall feel like smooth sandpaper. This will allow for great adhesion of any plaster applied on top.
- Next, apply first coat with a stainless steel trowel and allow to dry for 24 hours
- Once dried, apply your second coat creating the texture and design desired. Let dry for 48 hours before applying a sealer or wax.
It’s no coincidence that lime plaster has remained a popular choice—this is mainly due to the fact that it can be utilized for various purposes..
At Meoded, we offer Lime Plaster to beautify any living space. We only use high-quality materials that are environmentally safe, antimicrobial, and volatile organic compound (VOC)-free for your (health) and peace of mind.
Lime plastering is an old technique. However, just because it has been around for a while doesn’t mean you can’t use it nowadays!
This unique type of plaster can help create a cozy, comfortable vibe in your home that will have you never wanting to leave your house. And now that you know everything there is to know, it’s time to look for a lime plaster that suits your needs.