🧰 Sheet Membrane Waterproofing: Long-Lasting Protection for Northern Beaches Apartment Balconies

planab55
Aug 3, 2025
3 min read

Updated: Aug 10, 2025

If you manage or own an apartment on the Northern Beaches of Sydney, chances are your building’s balconies are exposed to harsh weather, salt air, and heavy rain. Over time, these conditions can cause serious waterproofing issues—leading to leaks, concrete cancer, and internal damage.

At Plan A Builders, we specialise in sheet membrane waterproofing—a durable, code-compliant solution for protecting multi-residential balconies from long-term moisture damage.

🏗️ Why Waterproofing Matters for Apartment Balconies

Failing waterproofing is one of the most common causes of balcony deterioration in coastal apartment buildings. When left unresolved, it can cause:

Water ingress into lower units
Concrete spalling and corrosion of reinforcement
Damage to interior walls, ceilings, and electrical systems
Growth of mould and mildew
Compromised balcony safety and structure

If your building is showing signs of leaking balconies, sheet membrane waterproofing is one of the most effective and long-lasting remedies.

🧱 What Is Sheet Membrane Waterproofing?

Sheet membranes are pre-formed waterproofing materials (typically made of bitumen, PVC, or rubberised compounds) that are applied in layers to the substrate. Unlike liquid membranes, sheet systems:

Provide consistent, uniform thickness
Have factory-controlled quality assurance
Offer greater resistance to movement and tearing
Are ideal for balconies, planter boxes, and podium slabs

Our team ensures that the substrate is properly prepared, the membrane is correctly overlapped and sealed, and all penetrations are flashed and detailed per manufacturer requirements.

🔍 When to Consider Sheet Membrane Waterproofing

Balconies are leaking into lower units
Visible cracks, bubbling tiles, or water stains
Damp smells in internal rooms below the balcony
Poor drainage or ponding water on balcony surfaces
Previous liquid membranes have failed

Our team will inspect and advise if sheet membranes are the right waterproofing system for your property.

📍 Sheet Membrane Waterproofing for Northern Beaches Apartments

Coastal suburbs like Manly, Curl Curl, Dee Why, Collaroy, Narrabeen, and Mona Vale face unique waterproofing challenges:

Salt-laden air accelerates corrosion
Intense UV exposure weakens inferior membranes
Frequent storm activity tests weak drainage systems

At Plan A Builders, we use sheet membrane systems designed for high-exposure environments and install them in compliance with the National Construction Code (NCC) and Australian Standards.

🏢 Case Study: Sheet Membrane Install in Collaroy

Plan A Builders recently completed a full balcony remediation project in a 10-unit apartment block in Collaroy. The existing membrane had failed, causing water damage to units below.

Our team:

Demolished tiles and screed to expose the slab
Carried out concrete repairs and slope correction
Installed a torch-on bitumen sheet membrane system
Rebuilt the screed and re-tiled the balconies
Provided a 7-year waterproofing warranty

The result? No more leaks, improved drainage, and higher unit value.

✅ Why Choose Plan A Builders?

✔ Experienced in multi-residential waterproofing✔ Licensed and insured for remedial building works✔ Sheet membrane systems from trusted suppliers✔ All work engineer-certified and council-compliant✔ Detailed quotes and progress updates✔ Locally based on the Northern Beaches

We work directly with strata managers, engineers, and owners to deliver waterproofing solutions that last.