Skip to content
BPindex — The Largest Building Products Directory in the UK

ProTherm Quantum PLUS+

A Quantum leap – lowering heights, gaining value at 8 Bishopsgate.

Building Products Index Ltd Blue Roof Systems, waterproofing Leave a Comment

View the Radmat entry on BPindex

Visit the Radmat website

Architect: WilkinsonEyre
Main Contractor: Lendlease

Radmat Products used:
ProTherm Quantum® PLUS+VIP Inverted Roof System|
ProTherm XPS Infill Insulation
Blue Roof System
EshaFlex 370 Waterproofing System
PermaQuik Hot Melt System
ReadySeal Liquid Applied Waterproofing Membrane
ProTherm G XPS X 300 and ULTRA Insulation Board
RockFace A2 Non-combustible Upstand Board
FOAMGLAS T3+ Insulation

Located in the heart of London’s financial district, 8 Bishopsgate is a 51-storey commercial tower reaching approximately 204 m in height. The building was designed by WilkinsonEyre with structural and services engineering by Arup and construction managed by Lendlease. The building comprises approximately 52,900 m² of high-grade office space, along with retail and amenity areas. Its form is expressed as a series of stacked shapes that step back as the height increases, creating terraces at several levels and culminating in a pavilion block at the top which houses plant, executive space and a public viewing gallery.

Structurally, 8 Bishopsgate uses a steel-frame superstructure supported by two concrete cores that provide the lateral stability. The floor systems use composite metal-deck slabs, and the façade is a double-skin glazed system incorporating interstitial blinds designed to reduce solar gain and improve energy efficiency. From a sustainability and amenities perspective the building is impressive: it was delivered to BREEAM Outstanding and EPC A targets. A key public amenity is the free 50th-floor “Lookout” viewpoint for visitors,this public viewing gallery has magnificent views across London.

Sustainability has been a key design driver from the project’s inception. The structure uses only the steel needed for each load, reducing total steel by 25% and saving around 5,000 tonnes of CO₂. A raft foundation cuts the number of piles, saving 3,000 m³ of concrete (about 300 tonnes of CO₂). The tower’s massing is carefully composed: each block is slightly rotated and cantilevered to create a dynamic stacked form that reduces visual bulk and relates to the varied surrounding townscape.

In the roof and upper plant zone, the pavilion block at the top accommodates major building services, including mechanical and electrical plant, and makes provision for photovoltaic panels and louvres to support the building’s carbon-reduction goals. As the tower’s stacked massing recedes at higher levels, it creates opportunities for a series of generous roof terraces at levels 9, 11, 25 and 26. These elevated external platforms provide valuable amenity space for building occupants, incorporating a combination of hard and soft landscaping to support both social use and visual interest. The terraces offer welcome access to fresh air and daylight within a dense urban context and afford expansive views across the City of London, contributing positively to workplace wellbeing and the overall tenant experience.

Radmat’s products largely contributed to the environmental savings for the roof and terraces. The use of state-of-the-art ProTherm Quantum Plus+ VIP system can reduce the thickness of inverted roofing systems without compromising thermal performance, whilst still achieving level thresholds.

The U-value was kept to an overall 0.25 W/m•K despite some of the features on the roofs making this difficult to achieve. ProTherm Quantum and XPS Infill insulation was used extensively on roof areas that required irregular shapes and keeping to a low height under the BMU track and plant machinery.

This working drawing for 8 bishopsgate show the intricate design plans for roof areas using ProThermQuantum Plus+ and XPS Infill insulation.

Radmat’s Blue Roof system was also a major factor in keeping to sustainability targets. Rainwater in an inner city or urban location provides a greater challenge, particularly on constrained sites such as in urbanised areas, or brownfield sites, where the use of underground tanks are difficult and/or costly.

The Radmat Blue Roofing system is explicitly designed to attenuate rainwater rather than drain as quickly as possible, significantly contributing to the SuDS requirements within a development by collecting and temporarily retaining rainfall (for a maximum of 24 hours) within the roof finishes before discharging at a controlled rate.

Radmat’s Blue Roof system consists of PermaQuik Hot Melt Monotlithic membrane and EshaFlex 370 Reinforced bitumen membrane, guranteeing the six Blue Roof levels at 8 Bishopsgate are completely leak free for the design life of the building.

Overall, 8 Bishopsgate demonstrates how a modern high-rise office tower in central London can integrate premium working environments, public amenity, sustainability standards and architectural distinction. Its stepped massing, generous tenant amenities, high-capacity active-travel facilities and the pavilion viewing gallery reflect evolving expectations in commercial tower design. The roof and plant zone reiforce how “the roof” in such buildings is not merely a cap but a critical performance zone, combining structural, mechanical, façade and amenity disciplines at height. The project offers useful lessons in early multidisciplinary coordination, flexibility in plant layout and the importance of detailed focus on high-level structural/maintenance zones, Radmat’s premium ProTherm Quantum Plus+ and Blue Roof systems ensure the integrity of these roofs for many years to come.

For more information on Radmat Products contact:
Contact sales@radmat.com
www.radmat.com

Using the 5th façade to help mitigate climate change

Building Products Index Ltd Insulation, Roofing Leave a Comment

View the Radmat entry on BPindex

Visit the Radmat website

A new report from the University of Southampton Energy and Climate Change Division of the School of Engineering, commissioned by the NFRC Charitable Trust, highlights some key steps that specifiers, building owners and home owners can take to use the roof to help mitigate the impacts of climate change.  https://www.nfrc.co.uk/docs/default-source/publications/roofing-industry/mrk173-nfrc-future-(p)roof-research.pdf?sfvrsn=79932a49_2&utm_source=PR&utm_medium=email&utm_campaign=future_(p)roof

©-JonLucas-Redclyffe-Road_MainWhilst the largest roofing trade association in the UK could be expected to promote the contribution roofs can make to managing climate change the award-winning environmental charity Hubbub also recognises the valuable contribution that roofs can make, so much so that one of its 10 ‘Asks’ in The Greenprint is to ‘Ensure no roof goes unused.’ https://www.hubbub.org.uk/the-greenprint

As a market leading innovative flat roofing system provider Radmat Building Products fully endorse the recommendations in the ‘Building resilience of roofing technologies in a changing climate‘ report and already have an aligned product range that fully supports specifiers in following this direction of travel and improving the built environment.

Building resilience of roofing technologies in a changing climate‘ recommendations:

  • ProTherm-Quantum-greyConventional (consolidated technologies); These are technologies that are consolidated in the market currently in both the residential and non-residential sectors, such as enhanced levels of insulation and improving airtightness.

Radmat’s range of insulation boards includes the most thermally efficient XPS insulation boards on the market and the Worlds thinnest inverted roof insulation boards, both ProTherm G XPS X ULTRA 300 SL and ProTherm Quantum PLUS+ are BBA certified.  Every roof is designed to optimise thermal efficiency within the design constraints of the roof or terrace.

  • Cool (highly reflective coatings); A cool roof is one that is designed to reflect more sunlight and absorb less heat than a conventional roof, typically flat or low sloped. A highly reflective type of paint, sheet covering, tiles or shingles can be used to achieve this.

Radmat’s single ply membranes and Liquid Applied Membranes provide light colour finishes for warm roofs, and our inverted roof systems can be finished with light coloured paving, porcelain tiles or energy capturing green roofs.

  • Anchorage-HouseGreen (vegetated); These are ballasted roofs that cover a conventional roof (typically flat) with a waterproofing later, growing medium (soil) and vegetation (plants).

Radmat’s MedO extensive, wildflower and biodiverse green roof range provide self-sustaining plant communities that replicate or replace the natural environment that was there before construction; enhancing both flora and fauna in the local environment as well as helping mitigating pollution, airborne noise, improve health and wellbeing and provide amenity.

  • Blue (vegetated with enhanced stormwater attenuation capacity); These are roofs that are designed to slow the drainage of rainwater collected above a roofs waterproof element, unlike conventional roofs which allow rainwater to drain quickly away from the roof.

Radmat’s Blue Roof systems provide roof level attenuation and discharge rate control, meeting the requirements for the London Plan 2021.  The installation of the Radmat Blue Roof system at The Forge won the Roofing and Drainage award at the AJ Specification Award 2020 and features in the NLA report ‘Resilient London’ produced for COP26.

To find out more about Radmat’s product range go to www.radmat.com, for design support to help mitigate climate change e-mail TechServices@radmat.com  or call 01858 410372.

 

Thinner by design ProTherm Quantum PLUS+

Building Products Index Ltd Roof insulation, waterproofing Leave a Comment

View the Radmat entry on BPindex

Visit the Radmat website

100-Liverpool-Street.Environmental issues influence the construction industry at every stage of the building process. Government legislation and the Building Regulations have become more stringent with every update, requiring more sustainable approaches, and driving the industry to design, construct and deliver more energy-efficient buildings.

Building balconies and terraces over heated space is problematic for architects, designers and contractors: in new-build applications, stringent regulatory requirements and long-term economic viability have created greater demand for improved energy efficiency, while roofing designers and installers must strive to keep overall construction as thin as possible.

In order to meet the required U-values, the insulation will sometimes be installed both on top of and on the underside of the balcony or terrace. Not only can this be time-consuming, technically challenging and pose a condensation risk, it can also add unnecessary costs and increase the overall thickness of the construction.

There remains a huge industry demand for thinner and better performing products that will have a smaller impact on constructability and function in use. These limitations can significantly impact the ability to meet the requirements of Approved Document Part L Approved Document Part M and NHBC Chapter 7.1 when designing inverted roof constructions.  Here the demand to insulate above habitable space can make it difficult for a designer to meet the backdrop of increasing thermal requirements whilst meeting the desire to maximise the glass façade and cater for a level threshold.

ProTherm_Quantum-PLUS-Hybrid copyInverted Roofing System market leader Radmat Building Products developed the ProTherm Quantum Inverted Roof Systems in 2014 to tackle exactly these issues, and in 2016 the BBA Certified ProTherm Quantum VIP Inverted Roof Systems; making it the first Vacuum Insulated Panel system to achieve such an accolade.  Since then, ProTherm Quantum VIP has undergone continual development, resulting in the BBA Certifying ProTherm Quantum PLUS+ VIP Inverted Roof Systems in 2020.

ProTherm Quantum PLUS+ consists of a rigid Vacuum Insulated Panel (VIP) robotically coated with an elastomeric waterproof coating, creating a robust ultra-high performance insulation panel with a Design Lambda value of 0.007 W/mK, potentially reducing insulation thickness to 72mm to achieve a 0.15 W/m2K U-value, as opposed to 220mm of Extruded Polystyrene (XPS) or 240mm of Expanded Polystyrene (EPS).

ProTherm_Quantum-PLUS-Pure copyProTherm Quantum PLUS+ can dramatically reduce the thickness of inverted roofing systems without compromising thermal performance whilst still achieving level thresholds.  Suitable for use in roofs, roof terraces, podiums, enclosed balconies over heated space, insulated walkways, green roofs and blue roofs ProTherm Quantum PLUS+ provides the thinnest and most robust state of the art insulation system for inverted roof construction.

Quantum-PLUS+-Architects-diagramWhether designing an inverted roof to achieve the lowest possible Surface Slab Level to Finished Floor Level (SSL-FFL) or rectifying unexpected slab of floor level issues, ProTherm Quantum PLUS+ provides the thinnest insulation solution for a given u-value in roof, roof terrace, podium and balconies over heated space.

Quantum-PLUS+-Step-diagramTo ensure every project achieves an optimal solution Radmat’s in-house Quantum Design Team provide a full service, from initial outline design and thermal calculation to pre-delivery site survey, providing a final design solution with layout drawings for sign off.  This comprehensive process considers the insulation thickness requirements early in the design process, highlighting potential threshold issues and providing the most cost effective solution to meet the target U-value.