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Spray Foam Insulation

Closed or Open Cell Foam Insulation

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Spray foam insulation is the latest technology in insulation solutions, but whilst there’s lots of explanatory information about how the chemicals work and how the insulation itself stops air flow, there’s little information on the cellular make-up of such insulation.

When it comes to selecting between closed or open cell foam insulation, you may find the choice easier than you thought – as it largely relies on property type.

Here’s the lowdown on both open and closed cell foam, and why the former offers a far more salient solution from a homeowner’s perspective…

Closed Cell Spray Foam 101

When you purchase spray foam insulation, you can select from two main types: closed or open cell foam insulation. This refers to the chemical make-up of the insulation itself.

Whilst both options are effective at blocking air flow through, the performance advantages do differ.

It is these performance types that make closed cell more appropriate for commercial properties that aren’t in use twenty-four hours a day, and open cell better for residential homes.

Closed cell foam insulation incorporates an insulating gas that is retained within the insulation, whereas open cell doesn’t hold anything – making it less dense overall, but giving a far more economical spread.

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Whilst spray foam insulation is not formulated with any toxins, pollutants or allergens, and will not give off any gases that are harmful, open cell foam insulation is a fully water-blown material

Open vs. Closed Cell: Which is Best?

When we refer to open cell foam insulation being less dense, it’s easy to assume that it’s less effective. It isn’t. It just works in a different way.

Open cell foam insulation is slightly more susceptible to moisture vapour, but this allows for a more controlled diffusion of the vapour overall. There is still no risk of damp or mould, as open celled spray foam insulation provides a far more superior seal than a closed cell equivalent.

Open cell foam insulation does have a benefit that closed cell can’t facilitate at all: sound proofing. The nature of the open cells mean that sound is caught within them, and cannot pass through, but in closed cell foam insulation, it simply passes around the cells and straight through, aiding sound transfer between rooms.

This makes open cell foam insulation much more desirable for residential properties, or for commercial properties that require a quiet environment.

Whilst spray foam insulation is not formulated with any toxins, pollutants or allergens, and will not give off any gases that are harmful, open cell foam insulation is a fully water-blown material.

This means that it is mixed half-and-half with water by specialist equipment as it’s applied. It dries quickly and effectively, with rooms able to be used again within 24 hours of the application.

However, closed cell foam insulation is not purely water blown, but also mixed with additional chemicals for installation. This results in a longer drying off period and a longer period of disruption within which you will not be able to use the rooms.

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Open cell foam insulation does have a benefit that closed cell can’t facilitate at all: sound proofing. The nature of the open cells mean that sound is caught within them, and cannot pass through, but in closed cell foam insulation, it simply passes around the cells and straight through, aiding sound transfer between rooms

Why Open Cell Spray Foam Has The Upper Hand

Environmentally speaking, open cell foam insulation has the upper hand, as it requires less raw materials and resources to manufacture it.

Whilst both types will reduce energy usage, and increase the energy efficiency of a property, open cell foam insulation is far more effective, making it the go-to material for homeowners who are seeking to drive down their bills.

The slightly lower density of the open cell spray foam insulation also means that it is considerably cheaper to install.

However, despite it being more of a residential option than a commercial one, spray foam insulation should still only ever be installed by an expert technician.

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