Client: Faithdean
Role: Specialist Sub-Contractor

• Warm Roof Installation
  Reinforcing Leadwork
  Bespoke Tapered Insulation
• Liquid-Applied Waterproofing

• • Luxury residential apartments roof and balconies
    Lead joint reinforcement using Sika FlexTape
    Labour intensive detailing to complex geometries
    1,125m² re-waterproofing using Sika Decothane Ultra
  • Combined PIR & VIP tapered insulation design
  • Sequenced to allow uninterrupted resident access

Located just moments from Buckingham Palace, Montrose Place represents prime London living with luxurious multi-million pound apartments, set within an architecturally refined building. Despite its prestigious setting and high-end finish, the property was experiencing issues with water ingress.

The traditional lead roof had begun to split along numerous roll joints, allowing water to track beneath the coverings and into the residences below. At the same time, the waterproof coatings to the balconies had deteriorated, creating further routes for water ingress and placing both internal finishes and structural elements at risk.

The main roof defined by an extensive arrangement of traditional lead rolls, each one demanding careful preparation to form a compatible and durable interface with the waterproofing system. Lead is inherently mobile, expanding and contracting in response to temperature fluctuations and any waterproofing solution had to accommodate this movement without restricting it.

To address this challenge, Sika FlexTape was applied across every lead joint, reinforcing vulnerable areas while preserving the materials natural flexibility. Each roof section was individually assessed and approached in a controlled sequence, with working direction adjusted to suit the changing gradients. The process demanded absolute precision and consistency, as every joint required strengthening to prevent future stress fractures while maintaining a seamless membrane finish.

The volume of rolls, junctions and architectural transitions made the detailing exceptionally labour-intensive. Upstands, penetrations, terminations and complex interfaces had to be encapsulated with care, ensuring complete waterproofing continuity without compromising the building’s classical aesthetic. The application had to be carefully programmed around narrow curing windows to guarantee correct adhesion and long-term membrane performance. Achieving uninterrupted detailing continuity across such intricate geometries required meticulous planning and expert execution.

The seamless, liquid-applied nature of Sika Decothane Ultra proved fundamental to the project’s success. By eliminating the need for mechanical fixings or vulnerable lap joints, the system created a continuous and resilient waterproof envelope. Every outlet, junction and penetration was integrated into a unified surface capable of withstanding UV exposure, ponding water and long-term environmental stress. The completed 1,000m² roof has delivered a durable, low-maintenance solution that aligns with the expectations of a high-value residential development.

Attention then shifted to the balconies, where both waterproofing integrity and thermal performance required significant improvements. The existing inverted roof build-up was stripped back, exposing the substrate so that defects could be rectified. Strict height constraints at the door thresholds meant that insulation depth was limited, prompting the specification of a combined PIR and Vacuum Insulated Panel solution. VIP technology offered exceptional thermal resistance with minimal thickness, making it ideally suited to maintaining critical interface levels while significantly enhancing energy efficiency.

The balconies themselves presented practical challenges. Many were compact, irregularly shaped and situated within occupied high-end residences, restricting access and requiring bespoke detailing rather than standard solutions. A tapered insulation scheme was introduced across each balcony to promote effective drainage; eliminating standing water and protecting the long-term structural integrity of the slab. This approach not only enhanced thermal performance but also safeguarded the waterproofing system against premature degradation.

Following the insulation, the balconies were fully encapsulated using Sika Decothane Ultra to ensure consistency with the main roof and to create a unified waterproofing strategy. The liquid membrane allowed for precise detailing around the handrail base plates, edges, upstands, door thresholds and service penetrations – areas historically vulnerable to leaks. The system’s inherent elasticity enabled it to accommodate differential movement between the insulated build-up and the structural slab, ensuring resilience under cyclical, thermal and structural stresses.

Throughout the programme weather exposure, confined working areas and the need to maintain safe and uninterrupted resident access demanded ongoing coordination and adaptability. Sequencing and labour allocation were continuously adjusted, ensuring the system’s performance was never compromised.

The completed project represents a comprehensive enhancement of Montrose Place’s roof and balcony elements. By combining advanced insulation technologies with a high-performance, liquid-applied waterproofing system, the refurbishment has delivered long-term durability, improved thermal efficiency and robust protection against the elements. The meticulous treatment of the traditional leadwork and the integration of tapered insulation schemes reflect the technical and high-quality building envelope worthy of its prestigious location.

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