Reinforced Concrete Deck Waterproofing

Reinforced Concrete Deck Waterproofing

PolyMaxx HA is suitable for waterproofing both new and existing reinforced concrete decks. Whilst the waterproofing system is the same for both applications, substrate preparation varies based on the concrete’s age, condition, and prior coatings.

Whether the deck is part of a podium slab, a cantilevered structure, balconies or walkways, all require careful preparation to ensure long-term adhesion of the liquid-applied deck waterproofing system.

Our PolyMaxx HA deck waterproofing system provides a durable, fully bonded waterproofing solution, compatible with both existing and new reinforced concrete decks, even those that have been previously coated, aged, or weathered.

New Concrete Decks

Substrate Considerations:

• Concrete must reach first‑stage cure (Approximately 28 days)
• Surfaces will typically have laitance on top
• Moisture can remain within the capillaries
• Early shrinkage cracks may be present

Preparation Requirements:

• Remove laitance mechanically or by high-powered jet wash (3000 psi)
• Vacuum and then wash clean with damp rags
• Confirm dryness using hand test / colour test
• Prime with PolyMaxx HA Primer

Existing Concrete Decks

Substrate Considerations:

• May contain contaminants, weathering, loose coatings or surface defects
• Cracks or voids may have developed over time
• Structural irregularities may affect adhesion

Preparation Requirements:

• Remove coatings, laitance, dust, and contaminants
• Repair cracks and voids using HydroCoat 203‑RM
• Ensure surface is dry, stable and structurally sound
• Prime with PolyMaxx HA Primer

Why PolyMaxx Works Well on Concrete Decks

PolyMaxx HA is highly suited to both new and existing reinforced concrete decks because:

• The fully bonded waterproofing system prevents water migration between the membrane and the concrete
• Excellent adhesion to primed concrete, whether new, aged or previously coated
• Reinforced resin provides long‑term crack‑bridging performance and accommodates natural slab movement
• Performs reliably on substrates with surface irregularities, historic repairs or varied conditions
• Rapid curing (30–60 minutes) enables efficient sequencing on construction and refurbishment programmes
• Durable and versatile, suitable for exposed, protected, and buried deck applications

PolyMaxx HA offers long‑term reliability across all deck types, including podium slabs, balconies, walkways, landscaped decks, zero‑fall roofs, and refurbishment scenarios.

Installer Requirements

To qualify for the 20-year PolyMaxx warranty, your new existing concrete deck waterproofing installation must be carried out by one of our PolyMaxx certified contractors and accompanied by full photographic and environmental documentation.

Contact Newton Waterproofing

Need project‑specific guidance? Our technical team can advise on:

• New vs existing concrete preparation requirements
• Curing, moisture and laitance considerations for new slabs
• Contaminants, coatings and repair approaches for existing decks
• Correct primer selection
• Protective or anti‑slip finishes for trafficked deck areas
• Integration with warm, blue, green or inverted roof build‑ups

For technical guidance, NBS specifications, or help selecting the correct system for reinforced concrete deck waterproofing, contact Newton’s technical team.