What Is A DPM?
14/10/2024A Damp Proof Membrane (DPM) is a crucial component in modern construction, designed to prevent moisture from seeping through building foundations and walls. Whether you're constructing a new building or renovating an existing structure, using a damp-proof membrane can safeguard your property from moisture-related damage, mould growth, and structural issues.
This article will delve into what a DPM is, its various types, and how to install it on concrete floors and walls.
What Is A DPM?
Damp proof membrane, also known as DPM, liquid DPM, and liquid waterproofing membrane, is crucial for protecting your structures from rising damp, seepage, and other moisture-related problems.
Our range includes both one-coat and two-coat DPM solutions available in a variety of tub sizes, ensuring that you'll find the perfect damp-proofing membranes for your project. Our selection includes industry-leading brands such as Ultra Floor DPM, with options such as Ultra Floor DPM It, and a sought-after Tilemaster DPM, such as Tilemaster Fast One Coat DPM. Additionally, we stock the popular Ardex DPM, Ardex DPM 1C, and a couple of go-to Mapei DPM choices; Mapei Mapeproof, and Mapei Mapeproof ESM.
Is Damp Proof Membrane Waterproof?
Yes, liquid damp proof membrane (DPM) is waterproof. Liquid DPM is a water-based waterproofing paint that can be applied to walls, floors, and foundations to create a barrier against water, vapour, and some chemicals.
It can be applied by notched trowels, or brushes and rollers to a variety of substrates, including brick, concrete, and stone. It's often used in construction for both internal and external applications.
It can be used in many applications, including:
Under screeds and renders
Under laminate or loose-lay flooring
To protect embedded joists in masonry
As part of a flood resilience system
Under tiles in bathrooms and kitchens
In food processing areas
On balconies
Choosing the Best Liquid Damp Proof Membrane
Ultra Floor Suppress It Two Coat Moisture Vapour Suppressant | ||||||
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2 Component, solvent-free, One Coat DPM. | One-coat solvent-free, low-viscosity, two-component epoxy resin. | Two-component, solvent-free epoxy resin. | Two-component epoxy product. | A single-component, two-coat rapid-drying moisture suppressant primer membrane. | Two-component, solvent-free, pure epoxy resin. | A solvent-free, low-viscosity, two-component, polymer-modified epoxy liquid waterproof membrane. |
Coverage When applied to a smooth surface using an A2 trowel: When applied to a smooth surface using a B2 trowel: | Coverage: 10kg Will Cover 18m² (Can Vary Depending On Moisture Level) | Coverage Examples: - Up to 15m² per 5kg tub on Powder Floated Concrete | Coverage: 16m² | Coverage: 16.5m² Based On Two Coats | Coverage: 20m² per 4kg unit. 5m² per 1kg | Coverage: Approximately 4.8m²/ltr (4m²/kg) e.g. when mixed a 5-litre unit will cover approximately 24m² per coat at 200 microns, and a 20-litre unit will cover approximately 96m² per coat at 200 microns. |
Fast curing– Ready To Receive Smoothing Compounds In 4 – 5 Hours | Walkable in 6 hours | Cure Time: 5 Hours | Cure Time: Within 6 hours | UltraFloor Suppress IT must be overlaid within 12 hours of the membrane curing to provide an absorbent surface for the suitable application of adhesives. | Setting Time: – at +10°C: 5-6 Hours – at +23°C: 3-4 Hours – at +30°C: 2-3 Hours | Walkability At 20°C: 6-8 hours. |
Suitable For Use On Surfaces With A Moisture Reading Of Up To 98% RH | Suitable On Surfaces With High Moisture Content (up to 98% RH) | Suitable where the moisture levels are 98% RH or less | For use on moisture levels of above 75% and below 97% | Designed to suppress residual construction moisture – up to 95% relative humidity in cementitious subfloors | Accommodates hygrometer readings up to 98% RH | |
Suitable For Use Over Underfloor Heating systems | Suitable For Underfloor Heating | It may be used over cementitious screeds incorporating warm water underfloor heating systems. | Can be used with underfloor heating systems provided the system has been fully commissioned as per BS8203 2009, Section 3, 3.11 Protection against heat, and BS 8204 Part 1 2003, Section 6.4.6. heated levelling screeds. It is not recommended for heated subfloors where wood floor coverings are to be installed. | When the product is to be used with underfloor heating, please contact UltraFloor Technical Services for further information. | If considering underfloor heating, the screed must be allowed to cure for a minimum 28-day period. | Must not be used over a subfloor containing underfloor heating. |
Suitable for use in a one-coat application on a wide range of substrates including concrete, sand & cement screeds and calcium sulphate screeds. | Suitable for heated concrete and cement/sand screeds. | It is suitable for use as a DPM to suppress residual moisture in concrete and sand/cement screeds | Apply over sand/cement screeds that are laid over an effective moisture barrier to control residual or constructional moisture | Use over a variety of substrates including concrete floors, sand/cement screeds and most absorbent construction materials. It is not suitable for use with very dense substrates. | Specifically developed to provide a water and water vapour barrier, or priming layer to concrete, screeded, rendered or masonry surfaces, steel and other vertical as well as horizontal hard surfaces. | |
Use On Heated & Unheated Calcium Sulphate Screeds | Can Be used On Anhydrite/Calcium Sulphate Based Screeds |
How To Install Damp Proof Membrane On Concrete Floor
Applying liquid DPM correctly is crucial for preventing moisture from penetrating through walls, floors, or other surfaces. Liquid DPMs are often used in basements, concrete floors, or wet areas to create a waterproof barrier.
Here’s a step-by-step guide on how to apply liquid DPM effectively:
Materials Needed To Apply Liquid DPM:
DPM (always check the manufacturer’s data sheet for suitability)
Paint roller (medium to long pile)
Paintbrush (for edges and corners)
Mixing paddle (if required)
Primer (if recommended)
Measuring tape or ruler (to measure surface area)
Trowel or brush (optional depending on product type)
Read more:
Step-by-Step DPM Application:
Prepare the Surface
Clean the Surface: Ensure the surface is clean, dry, and free from dust, debris, oil, or grease. This step is important for good adhesion.
Repair Any Damage: Fill any cracks, holes, or gaps with a suitable filler and ensure the surface is even and stable. Allow any repairs to fully dry.
Priming: Depending on the product, some surfaces may require a primer. Follow the manufacturer’s guidelines for the type of primer suitable for the surface material.
2. Check Conditions
Dry Surface: The surface should be dry, especially if applying on concrete or masonry.
Temperature and Ventilation: Ensure the application is done in the recommended temperature range, and in well-ventilated areas.
3. Mix the DPM (If Needed)
Mixing: Some liquid DPM products come in two-part systems, requiring mixing. Follow the instructions provided to ensure proper consistency.
4. Application of the First Coat
Apply with a Roller or Brush: Use a medium to long pile roller for larger areas or a brush for smaller areas, such as edges and corners.
Start at the furthest point and work your way towards the exit.
Apply the DPM evenly across the surface in smooth strokes, ensuring complete coverage.
Coverage Rate: Follow the manufacturer’s recommended coverage per square meter to apply the correct thickness.
5. Allow to Dry
Drying Time: Let the first coat dry completely, usually for 4-6 hours, depending on the product and ambient conditions.
The membrane will usually turn from a wet appearance to a dry, tack-free finish.
Avoid stepping on the surface during this time.
6. Apply the Second Coat (If required)
Second Coat: Apply the second coat perpendicular (at a 90-degree angle) to the first one. This helps ensure complete coverage and prevents pinholes or weak spots.
Even Application: Ensure this coat is applied evenly without missing any areas. If the manufacturer specifies multiple coats, continue applying additional coats as instructed.
7. Final Drying and Curing
Dry Completely: Allow the final coat to cure fully. This can take anywhere from 12-24 hours, depending on the product. Check the manufacturer’s guidance on full curing times.
This method ensures a strong, continuous waterproof membrane that prevents moisture ingress and keeps surfaces dry. Whether you’re looking for a damp-proof membrane for walls or floors, or working on a residential project or large-scale commercial build, our range ensures you have the best liquid damp-proof membrane options available. Should you need any DPM advice or support with your order, don’t hesitate to contact us via email at [email protected] or give us a call at 01604 859800.