In the simplest variants of screed, a layer or waterproof layer of mortar between 2 and 4 cm thick is spread over the subfloor, which prevents soil moisture from rising to the floor. This layer is made with a mortar made up of cement, fine, water-repellent aggregate and water, dosage: (1:3 or 1:4).

However, well-executed slabs must have a lower layer of gravel to prevent the rise of water due to capillarity, and an upper layer of concrete of at least 10 cm that contains a light reinforcement or steel mesh to avoid cracks.

This subfloor must be perfectly level and smooth, for which the upper surface is usually troweled, so that it can receive the finish or flooring for interiors. In the case of roofs, terraces and toilets, it is used to slope towards storm drains or toilets.

This flooring can be of many types. flagstones, marble, granite, travertine, natural or glazed ceramic tiles, colored cement mosaics, granite mosaics, carpets, wood, linoleum, vinyl floors), synthetic rubber), high-traffic paints, etc.

If the building has a reinforced concrete slab roof, it is usual to have it level, both to facilitate its construction and to serve as a base for placing a lime or plaster mortar ceiling. In this case, it is necessary to slope the plane of the roof to direct rainwater to the drains, for which a subfloor or slope layer of variable thickness can be used, whose thickness should not be less than 8 cm on the lowest side, nor more than 30 cm on the highest side. A layer of more resistant mortar is placed on this subfloor.

In self-construction or in very economical constructions, when the floor is formed with tiles with dimensions greater than 15 cm on a side, sometimes the concrete is replaced by brick rubble), broken stone or clean slag, duly tamped and watered with lime water.

The most used thicknesses, depending on the use of the screed, are:

Expansion joints must be made, 5 cm thick around the perimeter and creating areas (panels) smaller than 100 m². They must be filled with an elastic material.

The Etruscans are credited with the invention of concrete, which was used extensively by the Romans to build subfloors and slabs, fill walls and ramparts, form roof vaults, serve as a base for roads and causeways, and aqueducts, among others. For this they used calcined limestone which they then ground and used as a binder. In volcanic areas there were stones called pozzolans that were only ground and then mixed with aggregates and water to make concrete.

In all cases it was used as a filling material due to its relatively low tensile strength. Despite this and after two thousand years it can be found in the ruins of the Caracalla baths, the Colosseum in Rome and in multiple places where the Roman Empire expanded.

In the simplest variants of screed, a layer or waterproof layer of mortar between 2 and 4 cm thick is spread over the subfloor, which prevents soil moisture from rising to the floor. This layer is made with a mortar made up of cement, fine, water-repellent aggregate and water, dosage: (1:3 or 1:4).

However, well-executed slabs must have a lower layer of gravel to prevent the rise of water due to capillarity, and an upper layer of concrete of at least 10 cm that contains a light reinforcement or steel mesh to avoid cracks.

This subfloor must be perfectly level and smooth, for which the upper surface is usually troweled, so that it can receive the finish or flooring for interiors. In the case of roofs, terraces and toilets, it is used to slope towards storm drains or toilets.

This flooring can be of many types. flagstones, marble, granite, travertine, natural or glazed ceramic tiles, colored cement mosaics, granite mosaics, carpets, wood, linoleum, vinyl floors), synthetic rubber), high-traffic paints, etc.

If the building has a reinforced concrete slab roof, it is usual to have it level, both to facilitate its construction and to serve as a base for placing a lime or plaster mortar ceiling. In this case, it is necessary to slope the plane of the roof to direct rainwater to the drains, for which a subfloor or slope layer of variable thickness can be used, whose thickness should not be less than 8 cm on the lowest side, nor more than 30 cm on the highest side. A layer of more resistant mortar is placed on this subfloor.

In self-construction or in very economical constructions, when the floor is formed with tiles with dimensions greater than 15 cm on a side, sometimes the concrete is replaced by brick rubble), broken stone or clean slag, duly tamped and watered with lime water.

The most used thicknesses, depending on the use of the screed, are:

Expansion joints must be made, 5 cm thick around the perimeter and creating areas (panels) smaller than 100 m². They must be filled with an elastic material.

The Etruscans are credited with the invention of concrete, which was used extensively by the Romans to build subfloors and slabs, fill walls and ramparts, form roof vaults, serve as a base for roads and causeways, and aqueducts, among others. For this they used calcined limestone which they then ground and used as a binder. In volcanic areas there were stones called pozzolans that were only ground and then mixed with aggregates and water to make concrete.

In all cases it was used as a filling material due to its relatively low tensile strength. Despite this and after two thousand years it can be found in the ruins of the Caracalla baths, the Colosseum in Rome and in multiple places where the Roman Empire expanded.