EPS costs less than XPS and has the same performance.
Fake
The XPS has better characteristics in terms of compressive strenght, water absorption and resistance to frost/thaw cycles, coupled with high thermal performance in the long term, also due to the low risk of absorbing water and moisture.
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The XPS uses greenhouse gases.
Fake
Most of the commercially available XPS uses carbon dioxide as an expanding gas, a substance that is reclaimed by nature and reused. Moreover, the CO2 savings obtained during the service life of the XPS panels compensate by far the possible CO2 emissions that occur during its manufacture and installation.
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Compressive strenght is not so important on roofs.
Fake
Weight of the workers at work on the roof and particular snow load could compromise the dimensional stability of the product and consequently the loss of balance in the cover package. Both extruded polystyrene and polyurethane foam offer excellent performance of mechanical resistance.
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Is it always necessary to have a high mass in the roof to ensure good behaviour during summer?
Fake
The reference parameter for evaluating the summer efficacy of opaque structures is the periodic thermal transmittance Yie. This parameter is calculated taking into account: thermal conductivity, specific heat, thickness and density. The summer performance can therefore also be achieved with light structures made up of materials with good values of thermal conductivity and specific heat. In This perspective it is possible to consider combined solutions between materials with high thermal resistance and materials with high specific heat and not exclusively particularly massive solutions.
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The reaction to fire of the organic thermal insulators is inadequate and the use can be hazardous in case of fire.
Fake
It is wrong to expect a good thermal insulator to also be a fire barrier. It is not a visible material and its function is different. Then we try to think how many objects that make up our houses would end up burning before and better than an insulator used in the cavity or cover. Wooden furniture, curtains, sofas, blankets... the same beams at the sight of a wooden roof.
Organic thermal insulators such as POLIISO FB, which offer high fire performance (Euroclass B s1 d0), are commercially available.
Organic thermal insulators such as POLIISO FB, which offer high fire performance (Euroclass B s1 d0), are commercially available.
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To what temperature does the extruded polystyrene plate retain its shape? What about polyurethane panels?
For extruded polystyrene, the maximum operating temperature is + 75 °C. Permanent deformation can occur at higher temperatures: it is therefore advisable not to cover the panels with dark protections during the hot summer days.
As far as rigid polyurethane foam is concerned, since it is not a thermoplastic but thermosetting material, it can be used in a temperature range normally between -40 ° C and + 110 ° C. For short periods they can withstand even higher temperatures. Long exposures to temperatures may cause deformations to foam or coatings, but do not cause sublimation or fusions.
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Does polyurethane melt in case of fire?
Fake
Polyurethane is a thermosetting product, so in the combustion phase it does not melt, it does not release droplets or burning particles and it maintains its structure substantially intact during the pyrolysis and carbonisation phases.
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Unlike those of polyurethane, the thermal conductivity values of extruded polystyrene worsen as the thickness grows.
True
But thanks to new production technologies this limit has been exceeded. The new X-FOAM shims have improved lambda because they are made of heat-welded multilayer. This also solves the problems related to the laying of several layers of material.
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The insulating slabs in XPS and PIR panels are durable products?
True
The products in XPS and PIR have a useful life of more than 50 years which corresponds to the useful life of ordinary buildings.
Thanks to its closed-cell structure it does not undergo, under normal conditions of use, transformations caused by water absorption, compression, bagging, etc.
Thanks to its closed-cell structure it does not undergo, under normal conditions of use, transformations caused by water absorption, compression, bagging, etc.
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With what can I paste the XPS sheets and PIR panels?
XPS slabs can be treated fundamentally with all polystyrene-suitable adhesives. These include, for example, cold-applied bituminous adhesive sheaths, polyurethane adhesives and cement-based adhesives. In General, solvent-free adhesives should be used. Always adhere to the advice of the manufacturer of the adhesive.
The rigid polyurethane foam panels offer compatibility with bitumen, adhesives of an organic nature, excellent resistance to mechanical fixings assessed according to the Pull Through Test (Wind extraction load). In particular, for polyurethane products with aluminium support, it is advisable to use mono or bicomponent polyurethane glues because, being coatings without any porosity, it is difficult to absorb the humidity of the organic adhesives.
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What do you cut or shape the XPS and PIR panels?
The XPS extruded polystyrene foam insulating slabs can be cut, in order to give them a shape, with "cutter", hand hacksaws, electric, radial and also with hot wire.
The polyurethane panels, on the other hand, cannot be cut in hot wire or with electric hacksaws but only with rotating wire cutters, cutters, circular saws, hacksaws, etc.
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X-FOAM and POLIISO products can be eaten by mice, birds, etc.?
No, being a product derived from natural hydrocarbons does not constitute nourishment for any living being, including microorganisms. In some cases it may happen that small rodents or birds are trying to get their nest. It is therefore important to correctly lay the lateral flaps and accessories for the ventilation in order to prevent them from being accessed.
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Can XPS slabs be stored externally?
There are no contraindications. Clearly the polystyrene products, being light artifacts, require a bit of respect. The material produced is stored using a UV-resistant protective film to prevent the formation of the yellowish patina that can be created on surfaces exposed to the sun.