Foam floor insulation: technical and technological advantages

The constant increase in energy prices makes the issue of high-quality thermal insulation of premises more and more relevant. To carry out this event is not only to get the opportunity to save money on heating, but also to find a feeling of unclouded comfort. The right choice of insulation is half the battle. The construction market offers a huge variety of its varieties, to determine, of course, is not easy. Warming of square meters under your feet, among the whole range of “insulation measures”, is perhaps the most critical stage. Why? It is they who bear the main operational load – and the nature of the room does not play a special role here. The use of foamed polymeric materials, in particular floor insulation polystyrene foam, may be the best thermal insulation solution for your home.

Foamed polymers (in this case) mean foam, polyurethane foam, polystyrene foam, expanded polystyrene.


  • Styrofoam and extruded polystyrene foam?
  • Foam floor insulation
  • Penoplex – extruded polystyrene foam
  • Ground floor
  • On the insulation of the floor on the ground
  • Thermal insulation for heated floors
  • Heavy Duty Floors
  • Log floors


  • Benefits as a decisive factor

    Styrofoam and extruded polystyrene foam?

    Both extruded polystyrene foam and polystyrene have a “related” chemical composition, since both products are “derivatives” of polystyrene. But during the operation of both products (as a heater), it becomes obvious that the characteristics of these products still vary significantly. This is explained by fundamental differences in production technology..

    Foam manufacturing is a certain number of cycles of steaming raw materials with water vapor (polystyrene placed in a mold). As a result, there is an increase in the volume of granules and they “sinter”. In the process of growth of each of the granules, there is not only an increase in their surface, but an increase in micropores.

    The passage of time and external influences provoke weakening of bonds; there is a gap, the material simply “crumbles” into granules. Their weak physicochemical interaction explains the low strength of the foam (in particular, the reaction to bending) in comparison with the polystyrene product prepared by extrusion.

    Extruded polystyrene foam has a solid microstructure – this is the mass of closed cells that fill the gas molecules. Intermolecular chemical bonds are an order of magnitude higher than “foam”. The impermeability of the cells allows us to conclude that the penetration of liquid and gas from one to another is impossible. External access is possible only open (located on the side surfaces or sections) cells.

    Gradual (slow but steady) replacement of foam with extruded polystyrene foam is a worldwide trend.

    Penoplex is a domestic “nickname” of extruded polystyrene.

    Polyfoam is often called polystyrene foam, but when it comes to extruded polystyrene foam, remember – this is a material of the type “Penoplex”.

    Well, it’s time to move from theoretical to practical points.


    Foam packing process is a pleasure: plates are quickly laid, easy to cut

      Foam floor insulation

    Polyfoam is a often used material for floor insulation and not only. Warming the floor with its help is convenient, uncomplicated, and most importantly – not requiring significant financial costs.

    • Styrofoam plates (up to 50 mm thick) are laid on insulating material (plastic film);
    • The joints are sealed;
    • A wood chipboard (grooved), concrete or sand-cement mixture (about 6 cm thick) is laid next.

    It is a pleasure to work with this insulation, it is easily mechanically impacted, it is lightweight.

    Naturally, the main factor determining its popularity is cheapness..

    98% of the material is air, which, as you know, is an excellent heat insulator.

    Expanded polystyrene boards are not only an effective heat-insulating agent: they can be used to significantly reduce the transmission of impact noise (furniture rearrangement, steps).

    Three reasons to choose polystyrene as a heater:

    • thermal insulation (which goes without saying). This material is able to “keep” heat well (due to its high air content) – this allows you to save resources heating the room;
    • soundproofing. Give comfort not only to yourself, but also to your neighbors !;
    • durability. Polyfoam is able to last more than a dozen years, while not caking and not rotting.
    Warming of a wooden floor

    The insulation of a wooden floor with foam determines the use of a vapor barrier film

    Penoplex – extruded polystyrene foam

    Penoplex is a chemically biologically inert type of product with a low degree of combustibility.

    Ground floor

    The advantage of extruded polystyrene boards becomes extremely evident when building “basement” buildings (the floor of the first floor is located directly on the base).

    Polystyrene foam insulation is effective even under the most extreme operating conditions (humidity, low temperatures, mechanical stress).

    The closed-cell structure of the foam makes it possible to lay it under waterproofing membranes. The leveling layer is sand. The thickness of the underlying layer is from 100 mm. Waterproofing on top of thermal insulation should be done by “cold gluing”, excluding the presence of plasticizers and solvents in the adhesive.

    In practice, it looks like this:

    Floor insulation scheme

    Ground insulation on the ground – scheme

      On the insulation of the floor on the ground

    • level the base. An ideal option for loose soil will be its compaction;
    • it is advisable to let her settle down – from 14 days to a month;
    • pour a pillow of coarse gravel / gravel about 10 cm thick. Tamp it mechanically or manually;
    • lay a sand layer of the same thickness and compress the entire structure as much as possible;
    • if the screed or reinforced concrete slab acts as the base, the film is immediately laid on it. sheets of expanded polystyrene should be laid next to the film;
    • lay a metal mesh;
    • pour solution;
    • align the resulting plane with the leveling mass;
    • install flooring.

    At first glance, foam can seem very fragile, unreliable. Believe me, this is not so. Not only typical residential premises can be insulated with them, but also production facilities, garages.

    Thermal insulation for heated floors

    Thermal insulation becomes an absolute necessity in the presence of a floor heating system. The task of expanded polystyrene in this case is to reduce heat transfer in unnecessary directions. Due to the fact that the flow does not dissipate, energy costs are reduced. Otherwise, the heating, in addition to your floor, will be subject to the neighboring ceiling or basement.

    Expanded polystyrene is laid directly on the panel. And already on it a warm floor is “constructed”. To prevent the ingress of cement milk into the seams, adhesive tape will help.

    Schematically similar thermal insulation looks like this:

    Floor insulation polystyrene foam

    Thermal insulation of the heated floor with expanded polystyrene

      Heavy Duty Floors

    In the case of laying the foam on the leveling layer, the waterproofing is placed on top of it. A traditional roofing material can be laid under thermal insulation, directly on concrete. The wall-to-floor interface nodes are very important to protect from cold bridges.

    Log floors

    Place a polyethylene film on the base. Between the logs of the wooden crate, lay a heater. Such a floor arrangement provides a uniform load on the frame – in this case, not only extruded polystyrene can be used as a heat insulator, but also ordinary foam.

    Before mounting the structure, be sure to repair the cracks and other damage to the base – rodents do not need you.

    On top of the lag, lay OSB or chipboard, then install the necessary coating.

    Benefits as a decisive factor

    Expanded polystyrene is moisture resistant, fireproof. Its scope is unusually wide. In addition to floors, polystyrene foam is insulated with foundations, facades, walls, basements – and all this thanks to meeting the highest requirements for modern thermal insulants.

    Not only due to its thermal insulation properties is known the “foam family” – its “representatives” are also able to provide effective sound insulation (this characteristic is fundamentally important for industrial zones and megacities).

    Expanded polystyrene is environmentally friendly. Lightweight – easy to transport and install.

    Due to structural stability and stability, the material can rightly be called the optimal solution for the thermal insulation of floors and other surfaces in any of the climatic zones.


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