All about insulating with foam sealant
In a variety of applications, 2k pu foam, also known as PU foam, is the most effective form of thermal insulation. PUR is short for polyurethane and has a very high insulation value. 2K pu foam has maximum airtightness, ensuring optimal sealing of nooks and crannies of the space to be insulated. In addition, foam sealant is relatively quick and easy to apply as insulation. In this article, we will take a closer look at insulating with polyurethane foam. You can read exactly what foam sealant is and how it works in our other article on the properties of PU foam.
Types of PU foam insulation
PU foam insulation is available in different forms: sprayable PU foam and PU foam insulation boards. There is also 1-component PU in spray cans for small DIY applications. However, many polyurethane foam systems consist of two components and are suitable for all kinds of industrial applications: from shipbuilding to the petrochemical industry and the non-residential market. The most well-known are the Froth-Pak sprayable PU foam and the foam kit from Handi Foam.
Sprayable PU foam
PU foam insulation is always applied as a liquid after which it cures. This has the advantage that the PU foam gets into all nooks and crannies, thus sealing the space perfectly. Applying 2k sprayable PU foam can be done with different nozzles, depending on the application. A cone-nozzle is ideal for filling and injecting, while a spray-nozzle atomises the insulation material onto the surface. Sprayed PU is applied under high pressure after which it cures slowly or quickly, depending on the type of foam.
Besides sprayed PUR, it is also possible to use PUR insulation boards or moulded parts. These are cut to size and thickness in the factory from a large block of cured PU foam. The insulation value is the same as with sprayable PU foam, but in-situ foam works faster because you don’t have to measure everything in advance.
Advantages PU foam insulation
- The insulation foam cures quickly
- 2-component foam has a high insulation value
- Polyurethane foam insulation ensures perfect airtightness
- Applicable on surfaces with irregular shapes and indentations
- With sprayable pu foam, there is no need to measure everything first
- Lightweight but provides structural support
- Little to no waste
Cured PU foam
Thanks to the two components in the foam sealant, the foam insulation cures from about 30 seconds and is cured to a solid structure in five minutes. Within 10 minutes, the cured polyurethane foam can then be worked on. This makes it perfect for working through which is useful for large areas. But this quick curing time also makes it important to work accurately, as the foam also cures quickly on surfaces where it is not wanted. Once the PU foam insulation is on something, it is best to use a PU foam cleaner to remove it.
PU foam adheres firmly to most surfaces
With a foam gun, sprayable PU foam can be applied in a dosed manner to walls, ceilings, roofs and in cracks, among others. Polyurethane foam adheres to many building materials such as wood, metals and concrete. But also to plastics such as polyester, PVC and Styrofoam. It is a widely used insulation material in industry for good reason.
Polyurethane foam as insulation material
PU is a firm and dense foam that insulates well. This is due to the mass of closed cells that make up foam sealant. It holds dry air and it is this dry, stagnant air that ensures good insulation. Thanks to its high density, it not only insulates but also dampens sound. It also fills spaces, keeps odour and smoke out and provides additional structural support. Moreover, PU foam insulation resists temperatures from -120°C to 100°C.
Lambda value PU foam
An important criterion for the effectiveness of PU foam insulation is the Lambda value. This insulation value is an important measure and shows how much heat is lost through the PU foam insulation. The lower the value is, the better the insulation. This value depends on the layer thickness, but in general, polyurethane foam has a very high lambda value: 0.026 W/mK. Compared to other insulation materials such as glass wool (0.040 W/mK) and foam concrete (0.350 W/mK), this is a lot lower.
Sprayable pu foam is not only for insulating
However, foam sealant is not only used to insulate in industry, but is also used in many other applications. For instance, artists and builders of sets and floats also buy pu foam. They make light, yet sturdy shapes with the 2k pu foam. This is because cured polyurethane foam can easily be cut and modelled into the most complicated shapes.
Would you also like to buy PU foam for insulation?
Contact one of our specialists for advice or a quote. They are always at your service and together they will find the best insulation solution for your project.