Proven Waterproofing Performance

Suitable for use in warm roof build-ups or as a standalone waterproofing membrane, Proteus Pro-Felt® Ultima Plus offers a robust solution for both new-build and refurbishment projects. Manufactured with distilled bitumen and elasto-plastomeric polymers (APP), the system delivers consistent performance, flexibility and long-term protection.

The system includes the Ultima Plus Mineral Capsheet, a single-strand composite polyester reinforcement, which offers excellent mechanical strength and dimensional stability. When combined with Proteus Pro-Felt® SA Underlay or the Ultima Plus Sanded Underlay, it forms into a reliable, multi-layered waterproofing system.

Specialist Anti-Root Protection

Proteus Pro-Felt® Ultima Plus is also suitable for green roof applications or areas where planting is required, when using the Ultima Plus Anti-Root Capsheet, which provides more targeted protection. Designed with special additives and reinforced non-woven polyester, it resists root penetration and aggressive chemicals such as fertilisers and herbicides, without compromising the life and health of vegetation. The anti-root properties are permanent and are unaffected by weathering, water, or torch-on application.

Key Features & Certifications

• Fire tested - Achieves Broof(t4) performance.
• BBA Certified - Independently verified for a service life of 30+ years under normal conditions.
• Long-term guarantee - Backed by the 25-year Proteus Waterproofing Guarantee.
• Durability - Provides a resilient waterproof covering with proven dimensional stability.
• Certified quality - Manufactured to ISO 9001, 14001 and 45001 standards.

Why Choose Proteus Pro-Felt® Ultima Plus?

• High mechanical performance with APP-modified technology.
• Flexible specification for warm roofs, overlays, or as part of a built-up system.
• Root-resistant options for intensive or extensive green roof applications.
• Proven longevity with independent BBA certification and system guarantees.

Proteus Pro-Felt® Ultima Plus combines proven APP-modified bitumen technology with system flexibility and long-term certification, making it the ideal choice for architects, contractors and specifiers looking for a reliable, BBA-approved waterproofing solution.

As rainfall intensifies and planning demands grow, today’s buildings need smarter, compliant solutions. Proteus Attenu8® is a fully integrated attenuated blue roof waterproofing system that meets the toughest regulatory, thermal and SuDS requirements – all in one coordinated package.

A one-stop shop for blue roof design and delivery
Specify Attenu8® and you benefit from a complete solution - from first enquiry to final installation. It includes:
•    Total system design, bespoke to each project-specific requirement.
•    Dedicated technical support from our in-house specialist team.
•    Installation exclusively via approved contractors.
•    End-to-end service from early-stage planning to final commissioning and beyond.
•    A single point of specification and insured design responsibility.
•    Comprehensive insurance-backed guarantees covering every system component.

What makes Attenu8® different?
At the heart of the Attenu8® system lies the ACO Technologies patented drainage and overflow layer that separates water attenuation from the underlying roof drainage. This unique structure allows the drainage system to be independently engineered in line with BS EN12056:3 2000, unlike many competitor systems that obscure or override essential hydraulic principles.
This matters. Precise compliance with BS EN12056:3 enables engineers to accurately calculate flow rates under worst-case rainfall events, protecting clients from design errors, contractual disputes and regulatory non-compliance.
 

Technical advantages at a glance
•    Fully compliant with BS EN12056:3 and BS6229:2018.
•    Eliminates negative thermal performance in inverted roof designs.
•    Reduces required inverted insulation thickness, saving build height and cost.
•    Mitigates flotation risk without extra ballast, supporting lighter structural designs.
•    Compatible with substrates laid to falls (meeting NHBC and LABC preferences).
•    Ideal for new builds and refurbishments on existing falls-based structures.
•    Provides secondary waterproofing membrane for high-risk buildings.
•    Integrated overflow mechanism to meet 100-year rainfall events.
•    Full support for green roofs and bio-solar integration.
•    Re-usable, in line with circular economy principles in the London Plan.
•    Effective silt and debris management.
•    Easy to inspect and maintain in accordance with GRO and CIRIA C817.
•    Contributes to BREEAM when used with rainwater harvesting.
•    Reduces or eliminates need for below-ground attenuation tanks

Optimised for performance and circularity
The Attenu8® system is not just designed for compliance - it’s built for resilience. Its hybrid approach ensures thermal and hydraulic calculations are aligned, allowing for reduced design depths without compromising performance. It is also ideally suited to circular building practices, offering:
•    Reduced drain-down times that match hydraulic calculations.
•    All-year-round installation capability.
•    Full reusability and compatibility with circular building goals.
•    BBA certified to last for the life of the building on which it is installed.

The total integrated specification
The Attenu8® solution is more than just a blue roof - it's a fully integrated system covering:
•    Waterproofing
•    Thermal insulation
•    Water attenuation
•    Drainage
•    Green or solar roof compatibility
•    Compliance with planning, SuDS, and fire regulations
This joined-up approach reduces design risk, ensures consistent performance and removes the duplication and rework that often results from multi-supplier installations. By choosing Attenu8®, architects and specifiers gain certainty in performance and delivery, reducing pressure on the design team and supporting a "right first time" approach.
 

Guaranteed peace of mind
All Attenu8® systems are:
•    Installed only by approved Proteus contractors.
•    Covered by a single, insurance-backed warranty.
•    Backed by the combined expertise of Proteus Waterproofing and ACO Technologies.
•    Supported by full technical documentation and installation guidance.

Applications across all sectors
Attenu8® is ideal for a wide range of different application including:
•    Commercial buildings
•    Residential and mixed-use schemes
•    Data centres and critical infrastructure
•    Education facilities
•    Healthcare environments
•    Ministry of Defence and government buildings
•    Retrofit projects requiring SuDS compliance
Wherever water needs to be controlled, Attenu8® delivers precision, reliability, and compliance.

Start Your Project with Confidence
Whether you are in the early planning stages or developing detailed specifications, our team is here to help. We work with architects, specifiers and contractors to simplify the process - from technical advice and system design through to installation and post-completion support. To discuss your project or request a technical consultation, contact our expert team or download our Attenu8® specification guide.
 

This system has the ability to deliver integrated 'safe-seal' lap technology, to ensure the side-laps are sealed, creating a suitable vapour barrier. The glass fibre and aluminium composite reinforcement also provide additional strength.

The underside of the membrane is equipped with a separating foil to ensure reliable adhesion. The top side is finished with quartz sand, which enhances adhesion with subsequent thermal insulation.

Designed as a vapour barrier, Proteus Pro-Felt® Endura SA AVCL is suitable for cold-applied roofing systems. It can be applied to a wide range of substrates, including plywood, metal, and concrete decks, with the use of a suitable primer as required. This versatility allows for integration into various roofing applications.

The presence of quartz sand on the top side ensures firm adhesion with subsequent thermal insulation. Additionally, joints and overlaps can be sealed through (hot air) welding where necessary, to ensure a secure installation.

The vapour control layer offers strength and durability, while the underside of the membrane is equipped with a thermofusible polyethylene film to assist with installation and torch application. The top surface is finished with quartz sand, providing traction and walkability.

Designed as a vapour barrier membrane, Proteus Pro-Felt® Endura AVCL is suitable for torch-on roofing systems. It can be applied to a wide range of non-combustible substrates, including metal and concrete decks, subject to the use of a suitable primer as required.

With its aluminium reinforcement, the system is also resistant to alkali and corrosion.

Pro-Felt® Endura SA Underlay Sanded features a top layer saturated and coated with SBS modified bitumen to ensure protection against the elements. The system features a 200g/m² pure glass fibre reinforcement for strength and durability.

The underside of the underlay is equipped with a single layer removable film to assist with application. The top surface is finished with a sanded texture, providing traction and walkability.

Designed as an underlay membrane, Proteus Pro-Felt® Endura SA Underlay Sanded is recommended for use with the Proteus Torch-Safe System. It is compatible with a wide range of substrates and thermal roof insulation boards and can also be used with all common bituminous vapour control layers and cap sheets.

The System features a top layer saturated and coated with high-quality SBS modified bitumen, ensuring superior protection against the elements. The product also incorporates a strong 180g/m² polyester fleece reinforcement, providing excellent strength and durability.

For added convenience and ease of installation, the underside of the cap sheet is equipped with a thermofusible polyethylene film. This feature ensures efficient and reliable torch application, saving time on site. The distinctive slate surfaced finish also ensures that every project will look good once completed. The System incorporates a special graphite additive within the membrane, enhancing its ability to withstand fire.

Designed as a high-performance cap sheet, the Pro-Felt® Endura Mineral Anthracite is perfect for a variety of Proteus Waterproofing built-up roofing systems, whether it's a Torch-Safe or full Torch-On specification. The System is also compatible with all common bituminous underlay membranes.

The System features a top layer saturated and coated with high-quality SBS modified bitumen, ensuring superior protection against the elements. The membrane also features a robust 280g/m² polyester/glass composite reinforcement, guaranteeing exceptional strength and longevity.

What sets this product apart is the integrated 'safe-seal' lap technology, which enables easy, secure, and efficient sealing of side-laps.

To further enhance its capabilities, the upper layer of the membrane is shielded with slate mineral, providing additional protection and aesthetic appeal. The bottom layer is coated with a self-adhesive compound, ensuring convenient installation. This is covered with a removable film for added convenience and ease of application.

Proteus Pro-Felt® Endura SA Mineral Anthracite also delivers excellent fire performance thanks to a special graphite additive within the membrane. This enhances its ability to withstand fire.

Designed as a premium cap sheet, the Pro-Felt® Endura SA Mineral Anthracite is perfect for cold-applied roofing systems. It seamlessly integrates with Proteus' self-adhesive or torch-safe specifications and is compatible with Proteus Pro-Felt® Endura SA Underlay Sanded and Pro-Prime® SA, to provide a comprehensive roofing solution.

The Proteus Pro-Felt® Endura AIRdhesive incorporates a high-quality polyester reinforcement, ensuring maximum strength and reliability. Its upper surface is finished with a mineral coating, providing an attractive and robust layer of protection. On the underside, is a robust fleece finish, adding an extra dimension of quality and strength.

Proteus Pro-Felt® Endura AIRdhesive can be easily bonded using the Proteus Pro-Membrane Adhesive, mechanically fixed to suitable substrates or where suitable, fully torch applied to provide installers with the freedom to choose the method that suits the specific project requirements. For added convenience, this membrane can be specified as a completely flame-free waterproofing solution, ensuring a safe and efficient installation process. Furthermore, it serves as a fast-track method for overlaying existing roof coverings, saving time and costs.

Proteus Pro-Felt® Endura AIRdhesive delivers exceptional performance during installation, but its advanced formulation also guarantees outstanding functionality in a variety of conditions. It exhibits excellent flexibility at low temperatures, allowing it to withstand even the harshest climates. Additionally, it provides a high flow resistance at elevated temperatures, ensuring optimal performance under extreme heat conditions.

Torch-free installation

The Endura warm roof build-up features a self-adhesive air and vapour control layer (AVCL), which can be securely bonded to any roof deck without the use of a torch, eliminating hot works risks on site. This makes it a safe, efficient solution for both new-build and refurbishment projects.

Endura and the single layer Airadhesive can also be both part of a full insulated roof system or as part of a waterproof overlay where building requirements allow.

In addition, for suitable non-combustible substrates, Proteus Pro-Felt® Endura AVCL Sanded provides an alternative option, ensuring full compliance with stringent building requirements.

Thermal and waterproofing protection

The system is built up with Proteus Pro-Therm Insulation bonded directly to the AVCL, supported by a polymer-modified, self-adhesive underlay and a choice of capsheets. This multi-layered approach delivers outstanding thermal efficiency, robust waterproofing and long-term resilience, even under challenging site conditions.

As a direct waterproofing overlay or as part of a full Proteus Waterproofing built-up roof system, Proteus Pro-Felt® Endura membranes also provides elastomeric flexibility, high tensile strength and proven performance in demanding environments.

Bespoke system components

The Endura range also includes:

• Endura AVCL – A premium torch-applied vapour barrier for non-combustible substrates.
• Endura SA AVCL – A cold-applied, self-adhesive vapour control membrane with quartz sand surface for secure insulation bonding.
• Endura SA Underlay – An SBS modified self-adhesive underlay for cold-applied systems.
• Endura AIRdhesive – A fleece-backed, single-layer SBS modified membrane designed for superior adhesion and ease of application.
• Endura SA Capsheet – Cold-applied, self-adhesive capsheet with slate mineral finish for durable waterproof protection.
• Endura Mineral Anthracite – A torch-applied cap sheet with enhanced fire performance through graphite additive technology.

Why Choose Proteus Pro-Felt® Endura?

• Tested to Broof(t4) Fire Performance
• Certified for 35 years
• Under normal service conditions, the system will provide a durable waterproofing covering with a service life at least 35 years.
• 30-year Proteus Waterproofing® guarantee
• All products are certified to ISO 900, 14001 and 45001 accreditations

Proteus Pro-Cold® is suitable for new builds and refurbishments and can be used of a range of substrates. It cures to provide a seamless waterproofing protection, making it suitable for use in all climates.

Drip Edge Trim: A Right-angled trim to fulfil a smart finish of the edge of the roof.

Termination Bar: A neat and efficient means of terminating roofing and waterproofing membranes at wall abutments, they require no chases to be cut for installation. Usually used for a Built Up Felt Roof system.

Trims: This high quality, durable roof edge trim is manufactured from glass fibre reinforced polyester. These trims will create a neat, unobtrusive and durable finish for the edge of any flat roof.

F profile: Used for a Built Up Felt Roof System.

A Profile: Used for Mastic Asphalt and a Built-Up Roof System

Ideal for refurbishment projects, Pro-Cryl® can be applied directly to damp substrates and rusted metal. With no primer or additional solar reflection treatment required, Pro-Cryl® offers a fast and efficient cold-application that delivers long term performance, water tightness and protection against UV degradation.

With a rapid installation, Deckmaster offers cost and convenience benefits for both refurbishment and new build projects.

All Deckmaster waterproofing comes with a non-slip surface including a compatible line marking and signage system all of which ensure optimum practicality for all projects. Environmentally friendly with solvent-free, recycled components, Deckmaster can help to meet sustainability targets.

Cold Melt® DPM Primer is a liquid applied, damp proof membrane that can be applied to wet or damp concrete and polymer screeds after three days. This encapsulation of a damp/wet concrete deck will improve the quality and strength of the concrete.

Tapered Roof Design: Proteus Waterproofing can design tapered roof designs starting from the outset of the project.

Part B Fire Roof Design:

Low Threshold Terrace & Balcony Design:

Thermal Calculation & Condensation Risk:

When specifying or installing a Pro-Living® roof using Proteus’ unique Cold Melt® membrane, you are combining environment friendly materials such as recycled rubber crumb and organically grown products.

Choosing a Pro-Living® green or bio-diverse system from Proteus can provide ecological benefits and more; energy efficiency is enhanced too. Studies show a building’s internal air temperature remains more constant; hotter in winter and cooler in summer meaning air conditioning and heating systems are relied upon less.
Pro-Living® can help you to create a rooftop garden or communal space, a pleasant environment in which to spend time. Terraces can offer additional living space when created using a Proteus paving system. Walkways can meander through bio-diversity

Ideal for both refurbishments and new builds, Pro-BW® Plus is suitable for a variety of external applications. As it is a cold applied installation, the system meets health and safety criteria by minimising risk to both operatives and members of the public. Pro-BW® Plus reduces installation time from days to hours, is made in the UK and is BBA Certified.

In the dynamic field of construction, where effective moisture management is essential, the Proteus Hot Melt® system from Proteus Waterproofing Limited delivers a monolithic waterproofing layer suitable for various roof types. This hot-applied system, certified under British Board of Agrément (BBA) Certificate 22/6186, aligns with UK Building Regulations and provides a bonded membrane for flat roofs, terraces, podiums, and more. Architects, contractors, and property owners can rely on its documented performance for projects requiring consistent waterproofing.

This article examines the system's documented attributes and advantages, outlines general installation procedures, and discusses its compatibility with inverted roofs, blue roofs through the Attenu8® system, and green roofs via the Pro-Living® range. Based on technical specifications and guidelines, it highlights how Proteus Hot Melt® contributes to functional roofing designs.

Attributes and Advantages of Proteus Hot Melt®
The Proteus Hot Melt® system consists of a hot-melt compound, polyester reinforcement mesh, and a mineral-surfaced capsheet, forming a continuous membrane assessed for performance in demanding conditions.

Assessed Performance Characteristics
•    Weathertightness: The system prevents moisture ingress into the building, as evaluated in the BBA Certificate, making it applicable for inverted flat roofs (including zero falls), terraces, podiums, balconies, blue roofs, green roofs, and roof gardens.
•    Fire Performance: In specified protected configurations, the system achieves classifications that allow unrestricted use under Building Regulations, such as Requirement B4(2) in England and Wales, and Standard 2.8 in Scotland. Restrictions apply to balconies, and project-specific classifications should be confirmed.
•    Wind Uplift Resistance: The system's bond withstands wind loads, with performance tied to the roofing specification's upper layers, as per BBA assessments.
•    Mechanical Resistance: It accommodates limited foot traffic during installation and maintenance, as well as minor structural movements, without damage.
•    Root Resistance: Combined with Proteus Hot Melt Anti-Root Plain Capsheet, it resists root penetration, supporting green roof applications.
•    Service Life: When protected (e.g., by insulation or ballast), the system maintains waterproofing for the roof's expected lifespan, based on BBA evaluations.

Practical Considerations
•    Application Range: Compatible with substrates like concrete and various finishes, allowing use across multiple project elements.
•    Monolithic Structure: The application method minimizes potential weak points from seams, as detailed in installation guides.
•    Installation Efficiency: The pour-and-roll technique supports coverage with controlled material use.

Selecting Proteus Hot Melt® allows integration with roofing designs that meet documented standards.

General Installation Procedures for Proteus Hot Melt®

Preparation and Safety Measures
•    Health and Safety: Perform risk assessments and equip with PPE, such as heat-resistant gloves and eye protection. Adhere to Safety Datasheets and CLP Regulations for handling, with precautions against fire risks.
•    Storage and Handling: Keep components dry at 5–25°C for up to 12 months. Handle 25kg blocks manually and shield from weather on-site.
•    Tools and Equipment: Use boilers (heating to 180–200°C), rollers, and safety items like harnesses. Clean with solvent wipes after use.
•    Substrate Readiness: Inspect and repair (e.g., remove concrete laitance), clean via sweeping or vacuuming, and dry fully. Conduct adhesion tests on each area.
•    Priming: Apply DPM Primer at 0.2–0.3 l/m² with rollers or brushes, drying in 1–2 hours.

Installation Steps
1.    Compound Heating and Application: Maintain boiler temperatures at 190°C target. Apply at 1.5–2 kg/m² via pour-and-roll for uniform distribution. Seal incomplete sections daily.
2.    Reinforcement Mesh (Proteus Hot Melt® Force): Position polyester mesh, securing as needed, and embed in compound.
3.    Capsheet Placement: Prepare rolls, pour compound, and roll for adhesion with 100mm side laps and 150mm end laps. Proceed from low to high points on flat areas.
4.    Detail Work: Reinforce upstands, outlets, penetrations, joints, and edges with extra layers for seals.
5.    Adaptations: For zero-fall roofs, incorporate drainage per design standards. Inverted setups place insulation over the membrane.

Quality Assurance and Upkeep
•    Verification: Include site inspections, integrity tests (e.g., flooding), and daily reviews with records.
•    Maintenance: Check twice yearly for blockages or wear, clearing drains and addressing issues with matching materials.
•    Guarantees: Available post-installation by certified contractors, covering system performance.
These procedures, supported by Proteus training, align with standards for consistent outcomes.

Compatibility with Inverted Roofs
Inverted roofs position insulation above the waterproofing, and Proteus Hot Melt® supports this by providing a protected membrane that reduces exposure to temperature fluctuations and UV.
•    Advantages: Minimizes thermal bridging and aids energy performance, with options for ballast or paving.
•    Installation Notes: Apply directly to the deck, then add insulation and filters. Suitable for zero-fall layouts with appropriate drainage.

Integration with Blue Roofs: The Attenu8® System
Proteus Hot Melt® works with the Attenu8® blue roof for stormwater management, using modular cells to store and release water at rates as low as 0.07 l/s via flow restrictors.
•    Functionality: The membrane serves as the base, with Attenu8® forming a void above and a secondary layer for added security. Overflows manage high volumes per BS EN 12056-3:2000.
•    Advantages: Reduces runoff peaks, supports planning compliance (e.g., London Plan), and avoids flotation in inverted designs, enabling sloped roof adaptations.
•    Flood Management Alignment: Detains rainfall to lessen flood risks, fitting Property Flood Resilience principles for new and existing structures.
•    Installation: Build on the Hot Melt® layer, secure components with tapes, and top with finishes like paving or green roof.

Compatibility with Green Roofs: The Pro-Living® Range
Proteus Hot Melt® also pairs with Pro-Living® for vegetated roofs, incorporating sedum, wildflower, or diverse plant layers.
•    Suitability: Use the Anti-Root Capsheet to prevent root ingress, maintaining membrane integrity under vegetation.
•    Advantages: Contributes to drainage systems, moderates urban temperatures, and supports plant growth per BS 8217.
•    Installation: Layer over the membrane with root barriers, then add substrates and plants. Inspect annually for drainage and debris.
•    Applications: Effective for roof gardens handling soil loads.

Training, Assistance, and Assurances
Proteus provides site-based training on substrate assessment, application, and detailing, issuing 24-month certification cards (renewable). This supports compliant installations qualifying for guarantees.

In conclusion, Proteus Hot Melt® forms a verified base for roofing systems, compatible with inverted, blue (Attenu8®), and green (Pro-Living®) configurations. For specifications or inquiries, reach Proteus Waterproofing at enquiries@proteuswaterproofing.co.uk . Choose documented solutions for lasting roof performance.
 

Key Highlights

• Versatile Applications: Suitable for inverted roofs, podium decks, green roofs, balconies, terraces, and blue roofs as part of the Attenu8^® water attenuation system
• Overlay Compatibility: Can be applied over existing single-ply, felt or asphalt surfaces in inverted roofs after removing finishes and insulation, allowing reinstatement of finishes on completion.
• Accelerated Installation: Features Cold Melt^® DPM Primer, enabling application on substrates with up to 98% RH after just 3 days of concrete curing (subject to adhesion testing)
• Performance Benefits: Remains flexible without becoming brittle over time; no odour during application due to 100% solids content; tested to BS EN 1504-2 for protective coating