Damp Proofing

Damp Proofing Membranes (Above Ground)

Damp can cause long-term damage to internal wall finishes if left untreated. Damp proofing membranes provide an effective way to isolate moisture and salt contamination, helping walls to be finished cleanly and reliably.

Above-ground damp proofing systems include traditional studded cavity membranes as well as ultra-thin thermal membranes. Studded membranes create a controlled cavity between the wall and the internal finish, helping manage residual moisture while providing a stable surface for plaster, render or plasterboard. Thermal membranes such as ISO-THERM can also help improve cold internal surfaces while controlling damp, condensation and surface mould.

Above-ground damp proof membranes are commonly used as part of remedial damp treatments, including after a new damp proof course (DPC) has been installed. The correct system will depend on the source of moisture, the substrate and the required internal finish.

Waterproof & Dry stock a range of damp proofing membranes and associated products suitable for internal walls and floors, including:

• Slimline mesh-backed wall membranes
• Heavy-duty floor membranes
• Ultra-thin thermal wall insulation membranes
• Complete ISO-THERM insulation kits

If you’re working below ground, explore our range of basement waterproofing membranes, or browse our full selection of floor membranes.

Damp Proof Membranes for Walls

Where a property has been affected by damp due to a failed or missing damp proof course, installing a new DPC is the first step. Once in place, a damp proof membrane can be fixed to the wall to provide a dry, stable base for internal finishes.

Studded wall membranes create a small cavity, allowing residual moisture to dissipate safely. Many systems also include a bonded mesh surface, which provides an excellent key for plaster, render or dry lining.

This approach allows walls to be finished almost immediately, rather than waiting months for the masonry to fully dry out.

Mesh-Backed Wall Membranes

Mesh-backed damp proof membranes are designed for above-ground internal walls, providing a reliable key for finishes following DPC installation.

• Compatible with plaster, render and plasterboard systems
• Joints can be sealed using reinforced sealing tapes where required

Slimline Wall Membranes

For areas with limited space — such as window reveals or tight internal details — slimline membranes offer effective damp protection in a reduced profile.

• Ideal where maintaining internal dimensions is important
• Fix securely using specialist membrane fixings to maintain a sealed system

ISO-THERM Thin Internal Wall Insulation

ISO-THERM Internal Wall Insulation Membrane 7m² provides a different approach to traditional studded damp proof membranes. The ultra-thin 5mm woven polyester membrane is vapour permeable but waterproof, helping improve the thermal performance of cold internal surfaces while resisting lateral damp transfer and reducing the conditions that can lead to condensation and surface mould.

ISO-THERM is bonded directly to a suitably prepared substrate using ISO-THERM BOND PLUS Adhesive 15kg. The ready-mixed, polymer-enhanced adhesive is specifically designed for installing the membrane and typically covers around 7m² per 15kg bucket.

For convenience, the ISO-THERM Internal Wall Insulation Kit 7m² combines one 7.125m² membrane roll with one 15kg bucket of ISO-THERM BOND PLUS Adhesive, providing the two main components required for approximately 7m² of wall area.

• Ultra-thin 5mm profile helps minimise loss of internal space
• Helps improve cold internal surfaces and thermal comfort
• Vapour-permeable construction helps manage moisture
• Suitable for damp, condensation and surface mould remediation
• Can be plastered directly once the adhesive has dried

Damp Proof Membrane Installation Overview

Installation varies depending on the type of membrane being used.

Studded Damp Proof Membranes

1. Cut the membrane sheets to size.
2. Position on the wall, drill through and mechanically fix using suitable membrane plugs.
3. Seal joints and overlaps as required using compatible tapes.
4. Apply the chosen internal wall finish.

ISO-THERM Internal Wall Insulation

1. Prepare the substrate and cut the ISO-THERM membrane to size.
2. Apply ISO-THERM BOND PLUS Adhesive using a suitable notched trowel.
3. Fully bed the membrane into the adhesive and roll flat, fitting adjacent lengths side by side.
4. Allow the adhesive to dry before applying a multi-finish plaster and suitable breathable decorative finish.

Why Buy from Waterproof & Dry?

Waterproof & Dry are independent specialists in damp-proofing and waterproofing systems, supplying proven membrane solutions for domestic and commercial projects across the UK.

We offer fast UK delivery (typically 1–3 working days) and free technical advice from our in-house team to help you choose the right system for your project.

Need advice? Call our technical team on 0117 332 4747 — we’re happy to help.