Do I need membrane under fibre cement cladding?

What is Cladding Membrane

Normally known simply as ‘membrane’, there are numerous types of cladding membrane available on the market today, each with their own different benefits to consider. The three most common types of membrane are the Breather Membrane, the Vapour Membrane, and the Waterproof Membrane.

Breather Membrane

One of the most common types of cladding membrane, Breather Membrane is a water resistant membrane that protects your cladding and walls against water exposure from rain or snow. It is most often used for external walls and roof construction as a way to help deal with any water or moisture that the external cladding may be unable to handle.

The benefit of using Breather Membrane is that it is thick enough to resist any water exposure that gets through most external cladding while also being permeable enough to allow for proper insulation and ventilation.

The downside to Breather Membrane is that, because it is permeable to allow proper air ventilation, water vapour may be able to move through to cause potential condensation and dampness.

Vapour Membrane

A Vapour Membrane works at a much greater degree when compared to a Breather Membrane, as it results in the protection against water vapour as well. This results in considerably fewer incidents of potential water condensation or developing dampness on internal structures.

The downside to using Vapour Membrane is that, as somewhat of a reversal to Breather Membranes, makes the home potentially less ventilated due to the low levels of permeable air allowed to freely move through.

Waterproof Membrane

Waterproof Membrane are considered, by many, as the most effective in terms of blocking out water exposure. It is used as either a liquid or a sheet and can, depending on the specific quality, be made breathable while still wholly effective at protecting against water and water vapour.

Does Fibre Cement Cladding Need a Membrane?

Well, the answer is that it depends. Because fibre cement cladding is naturally very resistant against water and water exposure, there is a relatively low chance of water damage penetrating through and posing a risk to your home. The premixed fibre material acts innately as a form of resistance against water, meaning that in most cases it is not needed.

If, however, you are in an environment that is often beset by heavy or constant rains, are using a cheaper quality of fibre cement cladding, or are doing the project yourself, it may be a good idea to invest in one of the aforementioned membranes. While the fibre cement cladding will resist the majority of exposure, any amount that manages to slip through the cracks can safely be protected against by the membrane.