Specific weight of plaster and a table for calculating volumetric weight
Leveling walls inside and outside a building is a complex and labor-intensive process. Moreover, the final result directly depends on the material used by the worker. The construction materials market offers a wide range of plaster mixes. The most common are:
- Gypsum-based.
- Lime-based.
- Cement-based.
- Combined mixes (a combination of two or more types).
When choosing the right material, it is necessary to take into account the functional features of each type.
Calculating material costs for dry mixes.
At the very beginning of plastering work, both a professional and an amateur need to determine the amount of material required for successful work. A mandatory condition for achieving a quality final result is to follow all the features of the technological process. Calculations can be shown using such a parameter as the weight of dry plaster:
The average weight of one square meter of plaster is 15 kg. To calculate a more exact value, this weight must be multiplied by the layer thickness. An approximate calculation is shown below in the table.
| Plaster thickness | Weight of 1 m² (kg) | Specific weight (kg/m³) |
| 1 cm | 15 | 1500 |
| 2 cm | 30 | |
| 3 cm | 45 | |
| 4 cm | 60 | |
| 5 cm | 75 |
| Criterion / Plaster mortar | Gypsum-based | Lime-based | Cement-based |
| Vapor permeability | 0.11-0.14 mg/(m·h·Pa) | 0.10-0.12 mg/(m·h·Pa) | 0.09 mg/(m·h·Pa) |
| Consumption per 1 m² with a thickness of 1 cm | 8.5-10 kg | 12-20 kg | |
| Working setting time | 1.5 hours | 2 hours | |
| Working conditions | optimal conditions must be maintained | resistant to water and air exposure | |
| Need for puttying | not required | required | |
| Moisture resistance | none | present | |
| Bactericidal properties | does not have | has | |
| Strength | high | not high | |
| Versatility (interior and exterior work) | no | versatile | |
Based on the data provided, it can be said that all types of mortars have a number of advantages. They allow vapor to pass through well, without creating a “steam room” effect. There are also nuances during work: for example, gypsum has to be mixed more often and in small portions, because it dries faster. Cement plaster can increase the heat capacity of a room, which is a significant advantage. When working in damp rooms, a moisture-resistant mortar must be used.
As for cost, it varies depending on material consumption. Thus, the specific weight of cement-based plaster is twice that of gypsum plaster, so the weight of plaster per 1 m² will differ. The price of gypsum mortar is higher, which means there will be no significant difference in cost compared with a cement-sand mix.
Frequently Asked Questions
How much does 1 m² of plaster weigh at a 1 cm thickness?
The article uses an approximate value of about 15 kg per 1 m² at a 1 cm layer thickness. Actual consumption depends on the mix type, substrate flatness, layer thickness and application losses.
Why do gypsum and cement plaster have different weights?
Gypsum mixes are usually lighter and often consume about 8.5-10 kg/m² for a 1 cm layer, while cement-based mixes are heavier and may consume about 12-20 kg/m². For accurate calculation, use the data for the specific product.
How do you calculate the weight of plaster for a wall?
Multiply the wall area by the mix consumption for the selected layer thickness. For example, at 15 kg/m² per 1 cm, a 2 cm layer gives about 30 kg/m² before adding allowance for waste and uneven surfaces.