To calculate the amount of waste generated in a project, we will first estimate the amount of waste (total), expressed in tons T. The estimate is made based on the surface to be built (m² built) and to do so we will use estimating parameters, such as the height of the waste mixture (about 20 cm) and a type d density (1.5 t/m³ to 0.5 t/m³).

Then we carry out our detailed calculation for each of the different types of waste.

In a table we will indicate the estimated percentage (%) by weight of each waste and the estimated total of each type (∑=1), then calculating the amount of total waste.

We will conclude with the estimation of the waste volume V (m³) for each type according to the evaluated weight.

To calculate the amount of waste generated in a demolition, we must estimate the amount of each type of waste identified, estimating the apparent volume based on the weight and constructed surface and the type density.

Firstly, we classify the construction to be demolished according to the type of structure that supports it: factory, concrete or metal.

For each structural type we theoretically evaluate the volume of waste generated, estimating a weight p (m³ RCD for each m² built) that we apply to the built surface s, in order to calculate the apparent volume of waste V (m³) = p x s.

From this data we can estimate the weight in tons of waste for each type, according to the formula T = V x d, with d being the type density between (1.5 t/m³ to 0.5 t/m³).

We must specify whether the demolition is separative or integral, that is, mixed.

Inert waste is non-hazardous waste that does not undergo significant physical, chemical or biological transformations, is not soluble or combustible, does not react physically or chemically or in any other way, is not biodegradable, does not negatively affect other materials with which it comes into contact in a way that could lead to environmental contamination or harm human health. The total leachability, the contaminant content of the residue and the ecotoxicity of the leachate must be negligible, and in particular they must not pose a risk to the quality of surface or groundwater.[7]​.

In Spain, the Spanish Association of Technical Demolition, Cutting and Drilling represents the sector.

To calculate the amount of waste generated in a project, we will first estimate the amount of waste (total), expressed in tons T. The estimate is made based on the surface to be built (m² built) and to do so we will use estimating parameters, such as the height of the waste mixture (about 20 cm) and a type d density (1.5 t/m³ to 0.5 t/m³).

Then we carry out our detailed calculation for each of the different types of waste.

In a table we will indicate the estimated percentage (%) by weight of each waste and the estimated total of each type (∑=1), then calculating the amount of total waste.

We will conclude with the estimation of the waste volume V (m³) for each type according to the evaluated weight.

To calculate the amount of waste generated in a demolition, we must estimate the amount of each type of waste identified, estimating the apparent volume based on the weight and constructed surface and the type density.

Firstly, we classify the construction to be demolished according to the type of structure that supports it: factory, concrete or metal.

For each structural type we theoretically evaluate the volume of waste generated, estimating a weight p (m³ RCD for each m² built) that we apply to the built surface s, in order to calculate the apparent volume of waste V (m³) = p x s.

From this data we can estimate the weight in tons of waste for each type, according to the formula T = V x d, with d being the type density between (1.5 t/m³ to 0.5 t/m³).

We must specify whether the demolition is separative or integral, that is, mixed.

Inert waste is non-hazardous waste that does not undergo significant physical, chemical or biological transformations, is not soluble or combustible, does not react physically or chemically or in any other way, is not biodegradable, does not negatively affect other materials with which it comes into contact in a way that could lead to environmental contamination or harm human health. The total leachability, the contaminant content of the residue and the ecotoxicity of the leachate must be negligible, and in particular they must not pose a risk to the quality of surface or groundwater.[7]​.

In Spain, the Spanish Association of Technical Demolition, Cutting and Drilling represents the sector.