Scope and technology of laying floating floor screeds

In today’s construction industry, floating floor screeds are a flexible and effective solution that have many advantages for a range of building projects. Because they improve thermal and acoustic insulation and offer a level, long-lasting flooring base, these screeds are especially well-liked in residential and commercial settings.

One of the main characteristics of a floating floor screed is that it is separated from the underlying structure by being laid on top of an insulating layer. Because of its improved mobility and flexibility, this setup is less likely to break or sustain damage over time. Furthermore, because the insulation layer enhances heat distribution and energy efficiency, floating screeds are a great option for underfloor heating systems.

There are a few essential steps involved in laying a floating floor screed. The base surface must first be prepared, making sure it is dry, clean, and clear of any debris. Installing an insulation layer and, if required, a waterproof membrane come next. After that, the screed mixture—which is normally composed of cement, sand, and water—is poured and leveled. A strong and long-lasting finish requires proper curing.

Knowing the scope and technology of floating floor screeds can help you make well-informed decisions and produce high-quality results whether you’re building new or remodeling an existing space. By using this technique, you can enhance the overall performance of your flooring while also making your home more cozy and energy-efficient.

Features of floating floor screeds

Floating screed, also known as an "independent" floor, is a multi-layer cement-sand structure that is laid over an insulating layer rather than directly on the base as standard screeds are.

The layers of such a foundation are as follows:

1. thermal and sound insulation;
2. separating (waterproofing);
3. reinforced screed;
4. finishing layer.

It is advised to arrange these "pies" in the following ways:

• On "raw" bases, that is, if the primary subfloor was laid directly on the ground.
• If the floor covering is in direct contact with moisture, for example, if you are arranging an open terrace or veranda.
• If the room is subject to sudden temperature changes and excess humidity (bathrooms, baths and laundries).
• When installing "warm" floor systems.
• On the first floor of a private house, if there is an unheated basement under the room.
• When laying engineering systems in the screed itself (concealed installation).
• If it is necessary to reduce the load on the ceiling.

It’s important to weigh the benefits and drawbacks of floating floor screeds.

A flexible way to create level, long-lasting surfaces in residential and commercial buildings is to use floating floor screeds. This technique, which entails applying a layer of screed over an insulating layer, is perfect for areas where thermal efficiency and noise reduction are crucial because it provides flexibility and sound insulation. The process of installing floating floor screeds is simple and easy to understand; it involves base preparation, material mixing, and application technique that ensures an even and smooth surface. The numerous uses for floating floor screeds, their easy installation, and their advantages in contemporary building projects will all be covered in this article.

Advantages and disadvantages of a floating floor

The benefits of "independent" floors are as follows:

• The flooring is installed faster and easier (compared to a conventional "rigid" screed).
• The room remains warm, and the noise level from the street is reduced by more than 50%.
• The consumption of building materials is reduced (the layer of cement-sand mixture is no more than 4.5 cm).
• The finishing layer of the base is not subject to deformation under the influence of temperature fluctuations.
• Thanks to the intermediate layer between the screed and the base, there is cushioning when walking on the flooring.

The drawbacks are highly debatable when it comes to them. The cement-sand floating screed is thought to be chemically susceptible. However, by incorporating plasticizing additives into the mixture, which enhance the properties of the cement structure, this issue can be readily resolved.

Many people are also perplexed by how ugly the screed’s finishing coating looks. Everything in this case is up to personal preference, as any kind of flooring can be freely installed on the "pie" or a thin layer of self-leveling mixture can be applied to the screed before painting the surface.

Installation of a floating screed

The following is the order of work for installing a floating screed.

Preparation and marking

Prior to anything else, the old coating must be removed from the concrete base. Following that:

1. Clean the surface of the ceiling from dirt and dust.
2. Seal up deep and small cracks.
3. Treat the base with an antiseptic to prevent the formation of mold or mildew.

Following that, markings must be made. To do this, attempt to ascertain the future screed’s height as soon as possible, accounting for the cement-sand layer and the layers of sound and heat insulation (the latter should be approximately 45 mm high).

The next step is to draw two horizontal lines around the outside of the room. The lower line will represent the level of the insulation layer, and the upper line will represent the level of the screed.

Practical! The level of the insulation layer needs to be marked on the room’s walls if slab material is being used as insulation.

Installation of insulating layers

At this point, it’s important to consider the following suggestions:

1. If the floating screed is laid in a dry room, then a layer of polyethylene must be laid on the ceiling so that it goes onto the walls of the room.
2. If you are doing work in the bathroom, then you need to pay more attention to waterproofing. To do this, first treat the floor with bitumen mastic, and then lay the polyethylene. It is better to join the film with an 8 cm overlap.

Next, a damper tape is applied around the room’s edge (self-adhesive products work best for this). After laying the "pie," the tape is cut, so its height should be greater than the thickness of the screed.

Ensure that the floor is level before applying the heat insulator. If you see any unevenness, you can fill in the resulting depressions with sand to make up for it.

The following details need to be considered when installing the insulation:

• The material must cover the entire area.
• The insulation sheets are laid end-to-end, and the cracks are sealed with polyurethane foam.
• There should be no waves or bumps on the surface.
• If you are laying the insulation in several layers, it is better to arrange the sheets in a checkerboard pattern. This will prevent the formation of cracks between the seams.

Additionally, a polyethylene layer is applied to the heat insulator.

Installation of beacons and reinforcement

Using pre-made plastic "stands" as beacons is advised. Alternatively, you could use identically sized wooden blocks or heaps of cement mixture (based on the markings).

On the "stands," a reinforcing mesh (rod diameter: 1.5 mm, cell size: 40 x 40 mm) is placed.

The reinforcing frame should ideally be in the center of the screed when determining the beacons’ height.

Pouring the cement-sand mixture

In order to prepare the solution, combine the sand and cement in a 1:4 ratio. Then, dilute the mixture with water until it becomes a semi-dry mass. The solution shouldn’t crumble when formed into a ball, but it shouldn’t have too much water added either. It is advised to incorporate a plasticizer into the mixture, if at all possible.

Subsequently, the solution must be poured until the reinforcing mesh is reached, the surface must slightly dry, and then guides (wooden or metal profiles) must be installed, along which the second layer of screed will be laid and leveled.

The grouting of the screed and, if required, the removal of the guides come next.

Drying

Giving the finished screed the proper attention during the drying process is essential to preventing cracks and extending its lifespan. The advice that follows will assist you in this:

• The room temperature should be between +10 and +25 degrees, and the humidity should be 40-60%. Avoid drafts and sudden changes in temperature.
• It is recommended to “keep” the screed under a plastic film for the first week, wetting the surface daily. However, if condensation accumulates on the film, this indicates excessive over-humidification.
• After 3 days from pouring the screed, you can walk on it, after 5 – carry out repair work in the room (not related to the floor).
• After a month, the surface can be covered with a self-leveling mixture and install the floor covering or paint.

Floating floor screeds present a flexible option for contemporary building projects. They are a popular option for both residential and commercial buildings because of their versatility in accommodating different types of flooring while offering thermal and acoustic insulation. The technology enabling the installation of floating floor screeds has developed to meet the various demands of various construction environments while guaranteeing a seamless, long-lasting, and effective process.

The installation of a floating floor screed necessitates precise application techniques, appropriate material selection, and thorough subfloor preparation. In order to create a level, stable surface that will support the finished flooring, these steps are essential. To guarantee the durability and functionality of the screed, it’s critical to adhere to manufacturer instructions and best practices.

Knowing the basics of floating floor screeds, whether you’re a professional installer or a do-it-yourselfer, can greatly improve the strength and longevity of your flooring projects. You can accomplish a high-quality finish that satisfies the requirements of modern construction and renovation standards by using this method.

Video on the topic

THE EASIEST way to install beacons on the screed ⭕️ Few people know about it!

Floating floor screed on top of noise, sound, heat insulation, what is the minimum layer, how to make it.

Correct laying of screed (floating floor)

Vibrating beam for concrete, how it works.