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Valuable Insights to Flood Risks in Basements

Building Products Index Ltd Membranes, Waterproof Membranes, waterproofing Leave a Comment

View the Delta Membrane Systems entry on BPindex

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Flood risks are not always a primary concern during the design process of waterproofing below-ground structures.  Designers often focus on other aspects, overlooking the potential hazards associated with flood risk.  However, considering flood risks from the outset is crucial for ensuring the long-term safety of occupants and durability of these spaces.

Kevin Dodds, Managing Director at Delta Membrane Systems Limited, provides guidance on the essential considerations to reducing risks in below ground structures.

Flood Risks in Basements?

Basements are highly susceptible to flooding because of their below-ground location. Recognising the potential dangers of water entering these spaces is crucial when planning or maintaining a basement.  It is important to evaluate the likelihood of a flood event, which can occur due to heavy rainfall, increased groundwater levels, or other local flooding events. Addressing these risks can help prevent costly water damage, structural problems, and health issues.

Safety First – Means of Escape

A “means of escape” from a basement is a safe and unobstructed route that allows occupants to leave the building and reach a place of safety in an emergency (for example, fire).  In England, the Building Regulations guidance in Approved Document B sets out requirements for escape from habitable basement rooms, which typically must be served by an appropriate protected escape route and/or a suitable emergency egress window or door, depending on the specific layout and fire strategy.

In a flood, however, the usual route of escape via the staircase may be cut off, preventing occupants from reaching safety above ground.

Where flood risk is credible, consider another way out/means as escape such as a secondary exit at a higher level or a suitably designed emergency egress window/lightwell. Plan for situations where escape isn’t immediately possible: A managed place of refuge with a means of communication may be appropriate, aligned with the building’s overall fire and flood strategy.

Practical Tips for Mitigating Flood Risks

To reduce the chances of basement flooding, implement appropriate PFR (Property Flood Resilience) measures.

Routine inspections and maintenance of drainage systems, sump pumps and take steps to ensure that waterproofing protection system is suitably maintained can significantly lower the risk of water entry into a property. Use of monitoring systems on pump stations for surface water and ground water can provide early warning of increased risk of flooding and ensure appropriate actions can be taken prior to a flood event.

It should be recognised that it is not always appropriate to apply every possible property flood resilience (PFR) measure to a building. For example, where hydrostatic pressure during a flood could place the structure at risk, a controlled water-entry strategy may be preferable to full water exclusion.

Designers can influence flood performance at a variety of scales, from site planning through to component specification. It is vital that designers understand the range of strategies available to improve a structure’s flood resilience. Effective flood-resilient design can reduce exposure and vulnerability, limit damage, and support quicker recovery after a flood event. In practice, the strongest approaches is to plan for both water exclusion and managed water entry, depending on risk and context. The most cost-effective way to improve resilience is to implement appropriate measures as early as possible in the design process.

Flood Risk Assessment for Basements

Assessing site-specific flood risk is a critical early step in developing an effective design strategy.

Basements are particularly vulnerable to flooding due to their below-ground level position. When planning or maintaining basement spaces, it is essential to carefully assess potential flood risks. This includes evaluating the likelihood of water ingress during heavy rainfall, rising groundwater levels, or other local flooding events. Attention to these risks can help prevent water damage, structural issues, and potential health hazards.

The designer’s philosophy should set out what the PFR measures are intended to achieve and the principles that will guide the approach. A thorough risk assessment and a clear, robust design philosophy are essential when specifying a continuous system, as they will influence not only how the system is detailed and installed, but also the inspection, maintenance and any future repair or alteration requirements that ultimately affect the property owner.

Flood-resilient design should be viewed as an opportunity for joined-up thinking to develop better, more integrated solutions. There is no one-size-fits-all approach to successful PFR: each type of flood event has distinct characteristics that influence the suitability of the chosen strategy.  A suitable solution should reflect the building type and materials, ground conditions, conservation requirements and property owner needs.

Always Happy to Help

We offer expert waterproofing/PFR design and manufacturing collaboration, with PI insurance covering all design support and construction of our protection systems. Our installations are guaranteed and backed by a nationwide network of Delta Registered Installers.

Delta’s Technical Team provides timely advice and support for your project needs. Contact us at 01992 523 523 or info@deltamembranes.com.

Airtightness simplified and certified: a decade of Wraptite®’s BBA

Building Products Index Ltd Membranes Leave a Comment

View the A. Proctor Group entry on BPindex

Visit the A. Proctor Group website

November 16th 2025 marked ten years since Wraptite® – the self-adhered, vapour permeable, airtightness membrane from Proctor Group – first received a BBA certificate.

Wraptite’s development has mirrored changes in the UK’s building regulations and standards. Consistent improvements in energy efficiency and airtightness requirements have presented challenges to designers, specifiers and installers; Wraptite offers a simple solution.

Wraptite has become the go-to external airtightness solution – not just in the UK, but globally. The membrane delivers its combination of airtightness and vapour permeability in all climates, and its distinctive red colour is visible on construction sites and in modular factories around the world.

A brief history of Wraptite

Wraptite was originally developed for the North American market, where vapour impermeable solutions were common. By trapping moisture within timber frame structures, such solutions caused problems for occupants, like mould growth internally.

As building regulations in the UK continued to set stricter targets for energy efficiency, adding more and more insulation became less and less desirable. The law of diminishing returns when it came to improving U-values meant walls were getting too thick or insulation costs too expensive.

Other options were needed to help buildings perform, and specifiers and installers began to focus on airtightness. Tried and tested solutions were few and far between, however.

In 2015, a timber frame show home in Cambridgeshire provided the evidence people were looking for. The home targeted Code for Sustainable Homes Level 5, requiring a whole dwelling airtightness rate of 1m3/m2/hr. Part of the build used a typical internal air and vapour control layer (AVCL), and achieved 0.99m3/m2/hr – but only after applying extra tapes and seals.

Another part of the build used Wraptite and, with no remedial work needed, achieved 0.87m3/m2/hr. A new standard had been set.

Later that same year, Wraptite’s performance was effectively given an independent seal of approval with the issuing of its BBA certificate. Further certification has followed in the years since, and Wraptite is a Passive House certified component.

But it was the membrane’s BBA certificate that really helped to give Wraptite its foothold in the marketplace. Wraptite had shown that it could solve airtightness in one simple step; a BBA certificate provided the extra confidence people were looking for that it performed as the show home suggested.

Much imitated and never bettered

What makes Wraptite so successful? Its vapour permeability, perhaps. Maybe its peel adhesion or fire classification. Or the relative simplicity of its installation.

  • The facades and high-rise market has found many advantages in using Wraptite, like reduced material costs, shorter installation times and optimised building footprints.
  • Many projects seeking the Passivhaus standard (or similar) have turned to Wraptite to meet the required levels of airtightness, control moisture and deliver better occupant comfort.
  • Wraptite’s self-adhered nature fits perfectly with the efficiency of modular and offsite construction, and helps to protect modules during transportation far better than a mechanically fixed solution.

In truth, it’s the combination of Wraptite’s qualities that make it successful. That unique combination has also made it hard for competitors to imitate, and many have tried without bettering it.

Not all membranes are the same, and a product with a lower upfront cost rarely delivers either lower prices or desired performance levels.

Fundamental to Wraptite’s performance is meeting the requirements of BS 5250:2021 Management of moisture in buildings – code of practice. The standard sets a clear definition for how membranes should perform to be classed as vapour permeable or ‘breathable’.

With an sd value of 0.039m, Wraptite’s high vapour permeability easily meets that standard and means any construction moisture can dry out rapidly. Meanwhile, competing products offer a wide range of vapour permeability performance. Some have an sd value as high as 0.26m, which exceeds BS 5250’s upper limit for what a membrane should offer.

In other words, there are membranes claiming to be vapour permeable, which do not meet the basic definition of vapour permeability.

Wraptite features patented technology that helps to deliver its unique vapour transmission properties. One area of particular difference is in the adhesive. Wraptite’s adhesive is vapour permeable, which means it carries vapour to the membrane layer faster, and then allows it to pass through without accompanying air leakage. Most other membranes don’t enjoy that technology.

When it comes to peel adhesion and wind resistance, other products need tapes, adhesives, primers or accessories to support their installation. On a square metre basis, another product may appear cheaper. But if it needs bigger overlaps or additional accessories, or takes longer to install, then it suddenly becomes a lot less economical.

Overall, Wraptite’s track record is backed up by a comprehensive suite of testing and accreditation, as well as a warranty, that other products cannot match.

A lack of testing and certification is a particular concern when it comes to fire performance. There may be products marketed with certain levels of fire performance, but without the test data to back up those claims. With the construction industry’s renewed focus on fire safety, lack of evidence of performance is a significant risk.

A track record of success

Wraptite’s enviable track record in construction projects, plus its certification, means people can trust it will work and has been proven to do so.

One of Wraptite’s earliest breakthroughs, even before the Cambridgeshire show home, was its use on a 2013 project in Corgarff, Aberdeenshire, featuring double skin log cabins. A change in building regulations led to the project stalling. Manufacturers Sylvan Stuart experimented with Wraptite and found it delivered the required airtightness performance in a single, self-adhered layer – and suddenly the traditional construction method had a new lease of life.

Looking at the type of projects Wraptite is routinely used on today, it is fun to reflect on how it has developed from a unique solution for boutique projects to a global membrane product that features on some of the world’s most prestigious and groundbreaking buildings.

Reflecting Wraptite’s worldwide reach, the membrane was used on the refurbishment of the Sunshine Mosque dome in Melbourne, Australia. The complex structure of the Ottoman/Turkish-style mosque featured seventeen concrete dome roofs which were leaking. Wraptite was used as a watertight underlay and separation layer under the zinc finish.

Closer to home, ‘the Diamond Tower’ in Canary Wharf, London featured Wraptite being used in another unique application. To protect exposed structural steels from declension, Wraptite was applied as a temporary protection measure to ensure the Knauf Fire-Tek 160 fire protection would perform as intended once the facade cladding had been installed.

While Wraptite is typically installed on the exterior of walls and roofs, it has also been applied internally. Bower House used Motion Frame Ltd’s Comfort Frame system, an offsite-manufactured internal wall insulation solution that is isolated from the external walls. The system featured Wraptite and helped deliver energy bill reductions of 50%.

As a Scottish company, Proctor Group is delighted to see Wraptite being used to provide future generations with the highest quality learning environments – at the same time as rejuvenating communities. Funding availability has led to a surge in construction of new schools and community campuses, many seeking to achieve the Passivhaus standard.

Examples include: the multi-award nominated Riverside Primary; three different Tayside schools (Perth High School, East End Community Campus in Dundee, and Monifieth Learning Campus); Dumfries High School; and Currie Community High School in Edinburgh.

No mention of Passivhaus is complete without referring to the world’s first Passivhaus leisure centre. Wraptite was used at St Sidwell’s Point in Exeter, including in conjunction with cross-laminated timber (CLT). And when our Managing Director, Keira Proctor, conducted her own eco-house self-build project, she of course opted for Wraptite to provide the external airtightness layer.

Ten years of certification is only the beginning

As building standards evolve, the needs of the construction industry change. While other membrane manufacturers are busy trying to imitate Wraptite – some with limited testing, some with no third-party certification at all – we are busy continuing research and development on our class-leading product.

Climate change; building safety and the Code for Construction Product Information (CCPI); sustainability and environmental product declarations (EPDs). The construction industry does not stand still, and celebrating ten years of Wraptite’s BBA certification is not the end of the story – it is just the beginning.

Double Award Win Celebrates excellence in UK structural waterproofing

Building Products Index Ltd Membranes, Waterproof Membranes, waterproofing Leave a Comment

View the Delta Membrane Systems Limited entry on BPindex

Visit the Delta Membrane Systems Limited website

Delta Membrane Systems Limited was honoured with the ‘Sustainability’ and ‘The All Star’ Awards at The Property Care Association, Best Practice Awards ceremony this year.  This double win follows our double win in 2024.

We are pleased to announce our success at the Property Care Association Best Practice Awards, where we have received two prestigious awards!!

During a fantastic evening at the iconic Manchester United Football Club, Old Trafford, which brought together our industry’s top professionals, we were delighted to take home a winners trophy for the ‘Sustainability Award’, and ‘The All Star’, a remarkable triumph for everyone involved. These awards acknowledge the hard work, passion, and dedication of the Delta team.

Sustainability – Winner

Delta had entered their pioneering “HLA Plus”.  Delta’s HLA Plus is an advanced high-water level alarm offering real-time remote monitoring and notifications through the Delta Pumps App. The app features a user-friendly dashboard and numerous capabilities to safeguard pumping stations, ensuring continuous monitoring without subscription fees. The HLA Plus connects seamlessly to any new or existing system, providing both proactive and preventive functions. This smart technology is invaluable for property owners, facilities managers, service engineers, and waterproofing contractors.

The All Star – Winner

Delta nominated their Marketing and Communications Manager, Rachel Munro.  Rachel, brings a unique skill set to the industry, showcasing a bold commitment to innovation and excellence.  While construction roles are typically associated with on-site work, the industry’s success significantly relies on behind-the-scenes efforts.  Rachel excels in these areas, and she is also a prominent advocate for women in the waterproofing industry.

All winners, finalists, images & videos can be found here – https://www.property-care.org/events/2025-property-care-awards/

Commenting on the achievement, Delta MD, Kevin Dodds, said: “Delta’s commitment to innovation continues with the Delta HLA Plus, exemplifying our dedication to providing new and unique solutions.”

“The Property Care Association, Best Practice Awards are among the most prestigious in the UK. Winning these two awards demonstrates the exceptional work by our team at Delta Membrane Systems Limited.

“At Delta, we consistently strive to uphold integrity in all aspects of our business. We are committed to environmental stewardship and carefully manage our plant operations to ensure sustainable practices.”

“The introduction of new products holds significant importance, not only for the industry but also for Delta.”

He continued “We’re so proud of our achievements and in the competitive structural waterproofing market it is a challenge to stand out from the crowd – we have proved our ability to do just that!”.

“Congratulations to all, and let’s strive for continued success next year.”

Sympathetic waterproofing solution to historic structure

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View the Delta Membranes entry on BPindex

View Delta Membrane Products

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Overview

The former Bradford Odeon Cinema, saved from demolition by a local campaign, has been transformed into an exciting music venue, newly named “Bradford Live”. Built in 1930, the cinema hosted famous acts like the Beatles and the Rolling Stones in the 1960s before being left derelict for 23 years.

The venue will feature a main auditorium, smaller spaces for corporate events, weddings, and graduations, and will host business conferences, awards ceremonies, comedy shows, and family entertainment.

Construction started in 2021, with many original features, such as the ballroom’s art deco ceiling, being restored.

Delta Registered Installers, Timberwise (UK) Ltd having worked with the main contractor previously, were called upon to give assistance on a dry rot outbreak and to design a custom, robust waterproofing solution for the large underground basement.

The scope of the project was to provide a Grade 3 environment to a large existing large basement which will feature multiple bars, toilets, seating areas along with further excavation for lift pits, etc.

This complex project required a specialist to provide an efficient, compliant, and future proof approach.

Methodology

Timberwise (UK) Ltd collaborated with architects and the project team to provide a straightforward, effective approach. Their waterproofing design ensured a robust and suitable system that integrated seamlessly with the structure, adhering to BS 8102:2022 standards, Approved Documents, and industry Best Practice Guidance. This design emphasised continuity, proper sequencing and installation, and future maintenance and serviceability.

Timberwise (UK) Ltd specified a Delta Type C system.  A Type C waterproofing system, or cavity drain membrane system (CDM), effectively manages water ingress by creating a drainage cavity within the structure, directing water to a sump and pump or external drain. Key benefits include flexibility for both new and existing properties, a ‘failsafe’ design that doesn’t rely on external barriers, and reversible installation suitable for historic buildings.  The system’s discreet internal finishing and under-cover installation allow work to proceed regardless of weather conditions and reduce susceptibility to minor installation defects compared to surface barriers.

Before installation of the Delta Type C system, all existing walls and new concrete slab were treated with Koster Polysil TG 500 anti-lime inhibiter to seal the surfaces and reduce the leaching of ‘free lime’ which could cause blockages behind the membranes.

Attention was given to all wall/floor junctions and fillet seals were created.   Angles are potential stress points for waterproofing systems.  These crack endangered areas require special attention.

Delta PT, a high-density polyethylene (HDPE) cavity drain membrane which features a plastic mesh welded to its dimpled surface, serves as an impermeable damp proofing base for plaster or shotcrete, and functions as a water control and drainage membrane.   Delta PT was securely fixed to the internal walls using specialist fixing plugs, with Delta MS20 installed to floors.

Below the floor membrane perimeter drainage channels were sited within rebates allowing for suitable drainage of any future water ingress and this being diverted to suitable discharge point (on this occasion a mechanical pump system).

To ensure the Type C system was fully maintainable, inspection ports were located at every major change of direction.

The basement drainage system features four Dual Delta Pumping Stations, each with an individual high level water alarm (HLA) and battery backup systems to keep pumps running in event of mains power outage.

All floors and drainage elements were tested to ensure these would drain as the system was designed and BS 8102:2022 requirements were met.

A new lift pit waterproofing detail has been integrated into the elevator system, featuring a preformed liner sandwiched between concrete, enabling lift engineers to drill internally without compromising the waterproofing system.

The need to service and maintain the drainage elements of type C waterproofing systems is paramount to long-term success.  Timberwise (UK) Ltd, incorporated inspection ports in the perimeter channel and installed the sump pump in a location that allows easy access for periodic servicing.

After the Type C System was installed the all-important final integrity testing was undertaken to exercise the waterproofing system in worst case scenario.

Products Used

  • Delta PT
  • Delta MS 20
  • Koster Polysil TG 500
  • Delta Tape/Cornerstrip
  • Delta Drainage Channel
  • Delta Packaged Pumping Stations
  • High Level Alarms
  • Battery Backups

Case Study Results

The former Bradford Odeon Cinema has been transformed from an unused derelict building back to its former glory for many theatrical and musical performances to be enjoyed once again.

The project was delivered on time and to budget.

The client was delighted with Timberwise (UK) Ltd’s ability to collaborate throughout the build process, adapting to phasing and sequencing to provide a robust waterproofing solution.         

 

Airtightness simplified and certified: a decade of Wraptite®’s BBA

Building Products Index Ltd Breathable Membranes, Membranes Leave a Comment

View The A. Proctor Group entry on BPindex

Visit The A. Proctor Group website

November 16th 2025 marks ten years since Wraptite® – the self-adhered, vapour permeable, airtightness membrane from Proctor Group – first received a BBA certificate.

Wraptite’s development has mirrored changes in the UK’s building regulations and standards. Consistent improvements in energy efficiency and airtightness requirements have presented challenges to designers, specifiers and installers; Wraptite offers a simple solution.

Wraptite has become the go-to external airtightness solution – not just in the UK, but globally. The membrane delivers its combination of airtightness and vapour permeability in all climates, and its distinctive red colour is visible on construction sites and in modular factories around the world.

A brief history of Wraptite

Wraptite was originally developed for the North American market, where vapour impermeable solutions were common. By trapping moisture within timber frame structures, such solutions caused problems for occupants, like mould growth internally.

As building regulations in the UK continued to set stricter targets for energy efficiency, adding more and more insulation became less and less desirable. The law of diminishing returns when it came to improving U-values meant walls were getting too thick or insulation costs too expensive.

Other options were needed to help buildings perform, and specifiers and installers began to focus on airtightness. Tried and tested solutions were few and far between, however.

In 2015, a timber frame show home in Cambridgeshire provided the evidence people were looking for. The home targeted Code for Sustainable Homes Level 5, requiring a whole dwelling airtightness rate of 1m3/m2/hr. Part of the build used a typical internal air and vapour control layer (AVCL), and achieved 0.99m3/m2/hr – but only after applying extra tapes and seals.

Another part of the build used Wraptite and, with no remedial work needed, achieved 0.87m3/m2/hr. A new standard had been set.

Later that same year, Wraptite’s performance was effectively given an independent seal of approval with the issuing of its BBA certificate. Further certification has followed in the years since, and Wraptite is a Passive House certified component.

But it was the membrane’s BBA certificate that really helped to give Wraptite its foothold in the marketplace. Wraptite had shown that it could solve airtightness in one simple step; a BBA certificate provided the extra confidence people were looking for that it performed as the show home suggested.

Much imitated and never bettered

What makes Wraptite so successful? Its vapour permeability, perhaps. Maybe its peel adhesion or fire classification. Or the relative simplicity of its installation.

  • The facades and high-rise market has found many advantages in using Wraptite, like reduced material costs, shorter installation times and optimised building footprints.
  • Many projects seeking the Passivhaus standard (or similar) have turned to Wraptite to meet the required levels of airtightness, control moisture and deliver better occupant comfort.
  • Wraptite’s self-adhered nature fits perfectly with the efficiency of modular and offsite construction, and helps to protect modules during transportation far better than a mechanically fixed solution.

In truth, it’s the combination of Wraptite’s qualities that make it successful. That unique combination has also made it hard for competitors to imitate, and many have tried without bettering it.

Not all membranes are the same, and a product with a lower upfront cost rarely delivers either lower prices or desired performance levels.

Fundamental to Wraptite’s performance is meeting the requirements of BS 5250:2021 Management of moisture in buildings – code of practice. The standard sets a clear definition for how membranes should perform to be classed as vapour permeable or ‘breathable’.

With an sd value of 0.039m, Wraptite’s high vapour permeability easily meets that standard and means any construction moisture can dry out rapidly. Meanwhile, competing products offer a wide range of vapour permeability performance. Some have an sd value as high as 0.26m, which exceeds BS 5250’s upper limit for what a membrane should offer.

In other words, there are membranes claiming to be vapour permeable, which do not meet the basic definition of vapour permeability.

Wraptite features patented technology that helps to deliver its unique vapour transmission properties. One area of particular difference is in the adhesive. Wraptite’s adhesive is vapour permeable, which means it carries vapour to the membrane layer faster, and then allows it to pass through without accompanying air leakage. Most other membranes don’t enjoy that technology.

When it comes to peel adhesion and wind resistance, other products need tapes, adhesives, primers or accessories to support their installation. On a square metre basis, another product may appear cheaper. But if it needs bigger overlaps or additional accessories, or takes longer to install, then it suddenly becomes a lot less economical.

Overall, Wraptite’s track record is backed up by a comprehensive suite of testing and accreditation, as well as a warranty, that other products cannot match.

A lack of testing and certification is a particular concern when it comes to fire performance. There may be products marketed with certain levels of fire performance, but without the test data to back up those claims. With the construction industry’s renewed focus on fire safety, lack of evidence of performance is a significant risk.

A track record of success

Wraptite’s enviable track record in construction projects, plus its certification, means people can trust it will work and has been proven to do so.

One of Wraptite’s earliest breakthroughs, even before the Cambridgeshire show home, was its use on a 2013 project in Corgarff, Aberdeenshire, featuring double skin log cabins. A change in building regulations led to the project stalling. Manufacturers Sylvan Stuart experimented with Wraptite and found it delivered the required airtightness performance in a single, self-adhered layer – and suddenly the traditional construction method had a new lease of life.

Looking at the type of projects Wraptite is routinely used on today, it is fun to reflect on how it has developed from a unique solution for boutique projects to a global membrane product that features on some of the world’s most prestigious and groundbreaking buildings.

Reflecting Wraptite’s worldwide reach, the membrane was used on the refurbishment of the Sunshine Mosque dome in Melbourne, Australia. The complex structure of the Ottoman/Turkish-style mosque featured seventeen concrete dome roofs which were leaking. Wraptite was used as a watertight underlay and separation layer under the zinc finish.

Closer to home, ‘the Diamond Tower’ in Canary Wharf, London featured Wraptite being used in another unique application. To protect exposed structural steels from declension, Wraptite was applied as a temporary protection measure to ensure the Knauf Fire-Tek 160 fire protection would perform as intended once the facade cladding had been installed.

While Wraptite is typically installed on the exterior of walls and roofs, it has also been applied internally. Bower House used Motion Frame Ltd’s Comfort Frame system, an offsite-manufactured internal wall insulation solution that is isolated from the external walls. The system featured Wraptite and helped deliver energy bill reductions of 50%.

As a Scottish company, Proctor Group is delighted to see Wraptite being used to provide future generations with the highest quality learning environments – at the same time as rejuvenating communities. Funding availability has led to a surge in construction of new schools and community campuses, many seeking to achieve the Passivhaus standard.

Examples include: the multi-award nominated Riverside Primary; three different Tayside schools (Perth High School, East End Community Campus in Dundee, and Monifieth Learning Campus); Dumfries High School; and Currie Community High School in Edinburgh.

No mention of Passivhaus is complete without referring to the world’s first Passivhaus leisure centre. Wraptite was used at St Sidwell’s Point in Exeter, including in conjunction with cross-laminated timber (CLT). And when our Managing Director, Keira Proctor, conducted her own eco-house self-build project, she of course opted for Wraptite to provide the external airtightness layer.

Ten years of certification is only the beginning

As building standards evolve, the needs of the construction industry change. While other membrane manufacturers are busy trying to imitate Wraptite – some with limited testing, some with no third-party certification at all – we are busy continuing research and development on our class-leading product.

Climate change; building safety and the Code for Construction Product Information (CCPI); sustainability and environmental product declarations (EPDs). The construction industry does not stand still, and celebrating ten years of Wraptite’s BBA certification is not the end of the story – it is just the beginning.

Tensile and Compressive Loads – Structural Waterproofing

Building Products Index Ltd Membranes Leave a Comment

View the Delta Membranes entry on BPindex

Visit the Delta Membranes website

Tensile and compressive stress and strain are two common types. Tensile stress increases an object’s length, while compressive stress decreases it. These stresses help determine a material’s elastic modulus, indicating its stiffness.

Tensile and compressive loads are key in mechanics and engineering. Tensile load stretches materials, causing elongation. Compressive load compresses materials, causing them to shorten.

Tensile Strength

Tensile strength in structural waterproofing products is important to resist cracking and tearing under stress, preventing water penetration and ensuring a structure’s longevity.  High tensile strength is vital in areas prone to movement, where the waterproofing solution must withstand stretching and elongation without failing.

Tensile strength is measured by conducting a tensile test, also known as a tension or pull test, on a material sample. This test involves applying a gradually increasing tensile force to the sample until it breaks, while simultaneously measuring the force and deformation of the material. The maximum force the material withstands before breaking, divided by its original cross-sectional area, determines its tensile strength.

There are three types of tensile strength: Yield strength (A) is the stress a material can handle without permanent deformation. Ultimate strength (B) is the maximum stress it can endure. Breaking strength (C) is the stress level at the point of rupture.

A third-party tensile strength test evaluates a material’s resistance to breaking untder tension. Conducted by independent labs, it provides an unbiased assessment of mechanical properties. Results verify the material’s suitability for high-stress applications.

Not all third-party construction product testing is the same. The goal is to ensure product performance and compliance, but standards, processes, and rigor vary between testing bodies.

It’s important to follow manufacturer’s instructions for safety, optimal performance, and longevity of products and equipment. This prevents accidents, injuries, and damage, while maximising efficiency and meeting warranty requirements.

Tensile strength is vital for crack bridging products as it measures the material’s resistance to breaking under tension.  It enables the material to span and seal cracks without fracturing.  High tensile strength is essential to withstand the stress and strain from crack movement, preventing further damage and water ingress.

Compressive Strength

Tension is a force that pulls objects apart, while compression is a force that pushes objects together.

Compressive strength measures a material’s ability to withstand forces that crush or squeeze it. It represents the maximum stress a material can endure before fracturing or deforming significantly under compression. Essentially, it gauges how well a material resists being pushed together.

Compressive strength is vital for building materials, especially those supporting loads. It’s essential in concrete foundations, columns, walls, bricks, masonry, and insulation used in floors and roofs.

Foundations transfer the weight of buildings into the ground. Concrete, often used for foundations, undergoes compressive strength tests to ensure it can bear the load.

Columns are vertical structural members, often made of reinforced concrete, that support beams and floors. Their compressive strength is crucial to prevent buckling under heavy loads.

Load-bearing walls must withstand forces from above. Bricks, concrete blocks, and some insulation types need enough compressive strength for this purpose.  Floors and roofs must support the weight of people, furniture, and materials. Insulation in these areas needs strong compressive strength to avoid being crushed and losing its insulating properties.

Using materials with good compressive strength is vital for keeping a structure’s integrity.

Compressive strength of a membrane refers to its ability to withstand crushing or deformation under compressive force. It’s a crucial mechanical property, especially for membranes used in construction, insulation, filtration and waterproofing applications, where they may be subjected to significant loads.

Always follow the manufacturer’s guidelines for any construction or waterproofing product you use, regardless of general advice offered.

Manufacturer guidelines vary based on product types, materials, intended use, and regulations. These differences affect recommended installation, maintenance, and usage procedures due to each manufacturer’s unique processes and standards.

Ask Questions

We encourage you to ask questions about our products and services. Transparency and honesty are our core values. Enquiring helps us learn, understand, and grow. It allows us to gather information, clarify doubts, and gain deeper insights. By asking questions, we engage in critical thinking and problem-solving, essential for personal and professional development. This fosters communication, collaboration, and open dialogue, leading to better decision-making and problem-solving.

Training

Manufacturer training is vital for implementing best practices, enhancing skills, and boosting career opportunities. It keeps you updated with industry trends and new technologies, making you more competitive. Training also improves job performance, productivity, and confidence, leading to higher job satisfaction and personal growth.

Always Happy to Help

Delta’s office and field Technical Teams offer expert assistance to identify the ideal waterproofing system for your project, ensuring it meets your specific requirements precisely. For any inquiries about our products, we provide honest and accurate answers at all times.

Reach us at 01992 523 523 or drop us an email at info@deltamembranes.com.

Wraptite® external air barrier helps to create state-of-the-art learning environments for over 4500 Scottish pupils

Building Products Index Ltd Membranes, Uncategorized Leave a Comment

View The A.Proctor Group entry on BPindex

View The A.Proctor Group website

The specification and installation of A.Proctor Group’s Wraptite® external air barrier is helping three separate secondary school projects in Scotland to achieve the Passivhaus standard. As a result of the high-quality new school buildings, more than 4500 pupils will benefit from learning in thermally comfortable classrooms with excellent indoor air quality.

All three schools are being delivered by main contractor Robertson ConstructionTayside.With its purpose of assuring a sustainable future, Robertson has developed a specialism in Passivhaus construction, which supports its customers, local authorities and Government to address low carbon goals.

What are the three Passivhaus school projects where Wraptite has been specified?

The three schools are Perth High School, East End Community Campus in Dundee, and Monifieth Learning Campus. Construction commenced on all three within the space of a few months in the first half of 2023.

Perth High School was the first project to get underway.The current Oakbank Road building is more than 50 years old and rated ‘poor’ for suitability. It has been used beyond its design life.The new-build school will replace the existing facility when it is handed over in summer 2025.

Originally, a more traditional design and specification was intended for the construction, which will be used by 1600 pupils and 140 staff. The Passivhaus approach was adopted during the design process, and required minimal alteration to the building’s agreed form and location.

Two Dundee high schools also nearing the end of their life – Craigie High School and Braeview Academy – will be replaced by the East End Community Campus. Designed to accommodate around 1800 pupils, the site includes an integrated education centre for those with complex assisted support needs.

Expected to be handed over in summer 2025 as well, the campus’s sports facilities will be available to local groups and clubs. Some council services will be delivered from the new campus too.

The new education and community campus in Monifieth, near Dundee, features a new school for 1200 pupils and amenities including a swimming pool and Sport Scotland-standard athletics facilities. Angus Council’s intention is for the campus to be used fully, all year round.

Like Perth High School, construction is being phased so the new school is constructed while the old one remains in use.The existing facility will then be demolished once the new campus is up and running.

Installing Wraptite external air barrier to a variety of structural solutions

The external walls of each new school are constructed in a slightly different way, showing that the Passivhaus standard can be achieved using different construction methods. Building on and using its sustainable construction expertise, Robertson ensured the standard was capable of being met on these three projects.

“We wanted to take what we learnt delivering Scotland’s first certified Passivhaus school, Riverside Primary, and apply it to future projects,” said Kevin Dickson, Regional Managing Director, Robertson ConstructionTayside.“This opportunity came with the appointment to deliver three Passivhaus schools, constructed to realise each local authority’s vision while generating meaningful benefits throughout the process.”

A similar procurement process to Riverside Primary meant that using Wraptite satisfied the requirement for using local suppliers, on top of the experience gained in using it to meet the airtightness requirements.

Perth High School is a concrete frame with mineral wool insulation and a facing brick facade.The school buildings to the other two campuses feature a mix of concrete and steel frame, with high performance insulation. Facing brickwork is the finish at Monifieth, while East End Community Campus will have finishes of facing brickwork, precast concrete and cladding.

Wraptite is well-suited to Passivhaus projects, and the different construction methods demonstrate its versatility in helping to meet the standard’s high levels of airtightness. By moving the airtight line to the exterior face of the wall structure, it avoids a lot of complex detailing around services and other penetrations that typically occur at the internal face.

As a fully-adhered vapour permeable membrane, Wraptite saves on labour and material costs, without compromising airtightness levels and without increasing condensation risk within the structure. Not all detailing issues can be avoided, of course, and where particular areas of detailing do need to be addressed there is the added benefit of Wraptite tape.

On-site quality checks are a hallmark of the Passivhaus standard and accreditation.The simple solution offered by Wraptite allows those checks to be carried out with the minimum of fuss. Find out more: https://proctorgroup.com/products/wraptite

What is a ‘Cavity Drain System’?

Building Products Index Ltd Membranes, Waterproof Membranes, waterproofing Leave a Comment

View the Delta Membrane entry on BPindex

Type C, Cavity Drainage Waterproofing – Delta Membranes

Waterproofing Below Ground Structures RIBA Approved CPD

Technical Drawings Type C – Drained Protection – Delta Membranes

A “cavity drain system” is a structural waterproofing solution that isolates internal wall and floor finishes from water, water vapour and dampness. This article explores cavity drain systems and cavity drain products.

Structural waterproofing is a term which covers materials and/or techniques to stop water from entering a building, especially below-ground, by creating a barrier against groundwater or other water sources. Buildings globally depend on structural waterproofing systems.

A cavity drain system, or Type C, waterproofing system, protects below-ground structures (or any structure that is wholly or partially earth retained from water ingress by allowing water into enter into the structure (via ‘a cavity’) and safely draining it away.  A cavity drain system manages water entering a structure through external walls or floors, directing it behind a membrane into a controlled drainage system. This system safely diverts water to a disposal point, like a package pumping station.

Cavity drain systems are also known as Cavity Drained, CDM, Type C, Cavity Drainage and Cavity Protection. BS 8102:2022 ‘Protection of below ground structures against water ingress. Code of practice’ classifies Type C as “Drained cavity construction” and “Cavity Drained Protection.”

Key Components

Key components of a ‘cavity drain system’ are high-density polyethylene internal drainage membranes. These membranes are loose laid in flooring application, whilst being attached to the wall with surface plugs in vertical installations.

Water entering the structure is channelled into drainage systems (made up from basement drainage channels and collected in a submersible pumping station before being discharged at a suitable point. Additional key elements of a basement drainage system are high water level alarms and battery backups.

Cavity Drain Systems

A cavity drain system is fully maintainable, and an ideal solution for both new-builds, refurbishments, and historic buildings and structures. A cavity drain system offers a host of benefits, from easy and fast installation to ability to accommodate minor structural movements.

Cavity drain systems are highly effective and considered one of the safest and most reliable waterproofing methods.

Crossover

Certain cavity drain membranes can also provide protection in other fields. Such as AT 800, AT 800 is a cavity drain membrane that meets BS 8102:2022 and BS 8485:2015+A1:2019 standards, offering waterproofing and ground gas protection in one application. This membrane provides drainage protection in Type C waterproofing (Grade 3 environment) and acts as a barrier against Carbon Dioxide, Radon, and Methane gases. It also features high adhesion for applying flame retardants.

MS 500 Fire Retardant is an 8mm studded cavity drain membrane that achieves a Euroclass rating of B-S2, d0 (EN 13501-1:2018) and is suitable for internal walls and floors, protecting below ground structures from groundwater ingress with increased Fire Safety.

Need help with cavity drain systems?

For all your project requirements, Delta’s Technical Team is a dependable resource. Offering expert advice, comprehensive support, and timely practical assistance, we cater to your specific needs. Reach us at 01992 523 523 or drop us an email at info@deltamembranes.com.

Register Now For Building Safety for Future Generations

Building Products Index Ltd Acoustics, Membranes, Uncategorized Leave a Comment

View A. Proctor Group entry on BPindex

Visit A. Proctor Group website

A round table discussion on best practice for the implementation of the Building Safety Act across the industry. Our panel of experts will explore a range of topics around responsibility, risk and managing collaboration to deliver best practice safety management.

  • Industry Goals & Responsibilities
  • Stakeholder Collaboration & Accountability
  • Legislation, Compliance & Risk Management
  • Transparency, Documentation & Communication

Joining the discussion are leading industry experts:

• Iain Fairnington – Technical Director, A. Proctor Group Ltd
• Clare Fenton – Principal Facades Manager, Wates Group
• Peter Davies – Materials Engineer, Part B
• Gavin Hoccom – Partner, Browne Jacobson
• Will Jones – Head of Business Development, A. Proctor Group Ltd

Register now to reserve your place for our forthcoming Round table event “Building Safety for Future Generations” hosted by A. Proctor Group Managing Director Keira Proctor

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Webinar Certification 

Collect personalised CPD certification after you’ve viewed our webinar. This service downloads a PDF certificate which will appear at the bottom of your browser & will be saved in your downloads folder.

Webinar Product Sample Pack 

A pack containing samples of the materials discussed in our webinar can be posted out to you at your request.

Book An Online Meeting 

Our team are available to take online meetings (usually via the Zoom platform) at a date & time that suits you. We are happy to discuss project specific questions, review drawings, assist with specifications, documentation, calculations or anything else you need. Visit our website to start the process and we’ll get back in touch soon.

 

Safeguard Your Projects with Our Advanced Fire-Retardant Wall System

Building Products Index Ltd Breathable Membranes, Membranes Leave a Comment

View the DuPont entry on BPindex

Visit the DuPont website

In today’s building environment, the performance of materials is under increased scrutiny. DuPont has focused on improving fire safety with its comprehensive A2-s1, d0 system, which includes:

  • DuPont Tyvek® Trifecta™ Breather Membrane
  • DuPont AirGuard® A2 FR AVCL
  • DuPont AirGuard® FR System Tape

When used together, these products enhance both the exterior and interior fabric of a building. The combination of Tyvek® Trifecta™ with the DuPont™ AirGuard® A2 FR AVCL & Tape System delivers exceptional benefits in energy efficiency, moisture management, air quality, and overall comfort within the building.

This integrated fire-retardant system complies with the United Kingdom’s strict building regulations for fire safety with the assurance of a 25-year DuPont Warranty.

Explore more about our enhanced fire products here

Case study: Tyvek® Trifecta™ at a Major Hotel’s Expansion Project

When faced with new fire safety regulations, TKS sought our expertise to integrate Tyvek® Trifecta™ into their hotel design. Our Tyvek® specialists provided on-site training and a ‘toolbox talk’ for the installation team, sharing best practices for effective membrane application. This hands-on support continued over several weeks, ensuring compliance with building regulations and instilling confidence in the installation process.

With our commitment to collaboration, TKS not only met critical fire resistance standards but also transformed their vision into reality, creating a safe environment for hotel guests and staff.

Ready to elevate your projects with expert support? Discover more about our Building Knowledge Centre and the team available to provide expert guidance.

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