A Danrae Group guide to internal property membranes

Waterproof rain boots are standing in a flooded house

Danrae Group prides itself on expert waterproofing solutions from a skilled and diverse in-house team. With extensive expertise at hand, we’re fully equipped to provide waterproofing diagnostic, design, remediation and preventative maintenance for every type, and every section of a property… including interiors.

There are multiple elements to a quality waterproofing design, and at the core is a quality membrane. As part of every solution, our team will recommend best membrane options before providing end-to-end project management.

We take a look here at what you need to think about when selecting waterproofing membranes for interiors – and why your choice can have a long-term impact on property condition… and value.

Roll waterproofing

Waterproofing membranes need-to-know

Membranes are materials designed to block water ingress. They are typically used in areas including strata roofs and balconies, in retaining walls, and in damp interior areas like bathrooms, basements and lift shafts.

There are two main categories of membrane – liquid and sheet – and several subcategories.

The Danrae team often chooses a liquid membrane for internal applications, which may be water-based polyurethanes or cementitious type membranes.

In addition to repelling water, a membrane needs to withstand environmental conditions, accommodate normal structural movement, be breathable to permit the escape of moisture vapours and compatible with building materials. Ideally it should also be durable and easy to maintain.

Expansive interior membrane

Expansive interior membrane options

For new buildings, membranes are generally applied to the external wall face during construction. With an existing building, waterproofing can be applied from the internal side.

The general process will involve surface preparation of an internal wall to remove loose particles, grease and grime, then membrane application, with the technique dependent on membrane type. We generally use cementitious type membranes or water-based epoxies to withstand negative head of pressure.

To provide fully flexible waterproofing solutions, Danrae Group also supplements membrane replacement with additional services such as crack injection. Crack injection is a technique where polyurethane is inserted directly into cracks to repair and bind the concrete… and prevent water flow through the slab.

Black mold buildup in the corner of an old house

Protecting your property

So why is quality internal waterproofing so important? The primary function of waterproofing is to stop water entering a structure. Water that does seep into walls, floors or ceilings can impact a building in several ways.

Internal water damage can range from mould to concrete spalling and it can affect surrounding wall linings and finishes.

One key point with internal water damage is that it is often hidden from view.

Waterproofing issues such as concrete cancer or concrete spalling for instance, may already be well established before signs begin to appear on the surface of interior walls. And without intervention, damage is likely to escalate and require a larger and more costly fix.

Major repairs may also affect property value in the long term, particularly with strata buildings, where major repairs are recorded with strata history.

The Danrae Group team

Expert interior solutions

Whilst waterproofing membranes are central to effective waterproofing, not everyone can apply a membrane. Distributors will only sell to professional waterproofers trained in the specific membrane application.

The Danrae Group team is trained and qualified to work with every type of membrane and every brand, which means we can provide comprehensive waterproofing design… and give our customers full flexibility for a tailored solution.

Capability is a Danrae Group hallmark. And with builders, carpenters, tilers and other tradespeople at hand, we’re able to provide full project management and preventative maintenance to help preserve your property now and years into the future. Contact us for comprehensive internal waterproofing… from the experts. Read more articles about membrane waterproofing.

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