---
title: Polyurethane systems to improve sound insulation
description: Poor sound insulation is a problem for buildings and it has also an impact on the well-being and health of people. Would you like to know how to solve it?
---

[Synthesia Technology- Polyurethane Systems](https://blog.synthesia.com/en)

# [Polyurethane systems to improve sound insulation](https://blog.synthesia.com/en/polyurethane-systems-to-improve-sound-insulation)

 Written by [Synthesia Technology](https://blog.synthesia.com/en/author/synthesia-technology) | 09 July 2019

Poor sound insulation is a problem for buildings, not only in purely constructive terms, but it also has an impact on the well-being and health of its occupants. Therefore, the interior noise of buildings has become a problem that requires effective constructive solutions to ensure compliance with current regulations.

[**Synthesia Technology**](https://www.synthesia.com/)is a manufacturer and distributor of [polyurethane systems](https://blog.synthesia.com/en/polyurethane-systems-in-buildings) that have multiple applications in the construction sector and in other relevant sectors such as the industry. Below, we present a set of injected and sprayed **[polyurethane systems indicated to improve acoustic insulation](https://blog.synthesia.com/en/thermoacoustic-insulation-of-polyurethane-characteristics-and-applications).**

 

 

## **Systems of injected and sprayed polyurethane foam for sound insulation**

The **Phono Spray I-905, S-904 and S-907** systems are **thermoacoustic polyurethane systems** that are applied by “in situ” projection or injection, obtaining low and medium density rigid open cell foams with good acoustic absorption properties.

The application of these systems **improves the acoustic insulation** of the housing in a global way, while reinforcing the hygrothermal behavior of the enclosure, thus complying with the **regulations for protection against noise**. In addition, these systems do not contain foaming agents that damage the ozone layer.

 

 

### **Phono Spray I-905**

The [**Phono Spray I-905**](https://blog.synthesia.com/en/injection-moulded-polyurethane-insulation-for-facades-phono-spray-i905) injected polyurethane system is applied by casting with high pressure equipments, with heating, and a mixing ratio of 1:1 in volume. Its main application is **the improvement of the thermoacoustic insulation to the aerial noise** in enclosures of renovation buildings, as well in partitions between neighbors as in external facades.

The **adhesion** of the **Phono Spray I-905** system is excellent with all materials used in construction (concrete, ceramics, laminated plaster, wood, etc.) as long as they are clean, dry and free of dust and grease.

| Features |  |
| --- | --- |
| Apparent bulk density | 12±2 kg/m3 |
| Closed cells | <20% |
| Reaction to fire | Euroclass F |
| Water Permeability | ≤2 kg/m2 |
| Water vapor resistance factor (μ) | ≥5 |
| Acoustic absorption | 0,5 |
| Resistivity to air flow r | 5-6 kPa s/m2 |
| Free applied density | 18±2 g/l |
| Thermal conductivity | 0,038 W/mK |

 

You can see its application in the following video:

 

 

 

### **Phono Spray S-904**

The [**Phono Spray S-904**](https://blog.synthesia.com/en/projected-polyurethane-facades-phono-spray-s-904) system is applied by "in situ" projection, obtaining open cell foam of low density (9-11 g/l) with good acoustic absorption properties. Its objective is **the improvement of thermoacoustic insulation against airborne noise**, and it can be applied both in partitions between neighbors and in façades.

| Benefits |  |
| --- | --- |
| Apparent bulk density | 10±1 kg/m3 |
| Closed cells | <20% |
| Reaction to fire | Euroclass F |
| Water Permeability | ≤3.5 kg/m2 |
| Water vapor resistance factor (μ) | ≥5 |
| Acoustic absorption | 0,5 |
| Resistivity to air flow r | 5-6 kPa s/m2 |
| Free applied density | 10±1 g/l |
| Thermal conductivity | 0,037 W/mK |

 

You can see its application In the following video:

 

 

 

### **Phono Spray S-907**

The main application of the [**Phono Spray S-907**](https://blog.synthesia.com/en/projected-polyurethane-insulation-for-floors-phono-spray-s907) is **the improvement of acoustic insulation to noise in floors**, especially to impact noise in horizontal divisions, thanks to its porosity and elasticity. The system is applied by projection "in situ" obtaining medium density open cell foams (55-65 kg/m3). **Phono Spray S-907**, like the previous systems, is a constructive solution that improves the overall thermoacoustic insulation of the building.

| Benefits |  |
| --- | --- |
| Apparent bulk density | 55±10 kg/m3 |
| Closed cells | <20% |
| Reaction to fire | Euroclass F |
| Water Permeability | ≤1 kg/m2 |
| Water vapor resistance factor (μ) | ≥5 |
| Acoustic absorption | 0,32 |
| Resistivity to air flow r |  - |
| Free applied density | 43±3 g/l |
| Thermal conductivity | 0,037 W/mK |

 

It is recommended to apply the Phono Spray S-907 in the lower number possible of sprayed layers in order to achieve the desired thickness You can see its application in the following video:

 

 

 

[View full post](https://blog.synthesia.com/en/polyurethane-systems-to-improve-sound-insulation)

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