New legislation from the Welsh government, which came into effect on 7 January 2019, stipulates that all new developments of more than one dwelling or where the construction area is 100m2 or more should have Sustainable Drainage Systems (SuDS) in place.

From this date onwards, SuDS on a new development must be designed and built in accordance with the Statutory SuDS Standards published by the Welsh Ministers, while SuDS schemes must be approved by the local authority acting in its SAB role, before construction work begins.

Alumasc WMS have always worked with the philosophy that surface water from both roof and ground level is a valuable natural resource which should be managed in a way that reflects this. This is not only in the interests of the surrounding environment but also to create better places for people to live, work and play.

With this in mind, we believe water management should be considered from the beginning of the development process and throughout, and that it should positively influence the design and layout of the project or space.

So, how can you implement SuDS in your project when it comes to roofing and water management?

The core aim of SuDS is to manage rainfall in a way as similar to the natural process as possible, making use of surrounding landscape and natural vegetation to control the volume and flow of surface water. The benefits of SuDS can encompass flood risk reduction, enhanced biodiversity, creation of natural habitats for wildlife, contribution to better mental health and much more.

Both Green and Blue Roof systems offer SuDS measures, intended to significantly reduce peak rates of rainwater runoff, especially during heavy rainfall. This is not limited to during the event of a storm. As a general rule in the UK, London and East Anglia receive high intensity rainfall incidents, whereas western aspects of the UK generally receive higher total rainfall. So, its not just Cardiff, officially the UK’s wettest City, but the whole of the UK that would benefit from Green and Blue Roof technology.

Green and blue roofs do this is in different ways but can be used in conjunction with each other. Blackdown Greenroofs, for example, retain rainwater through plant absorption and provide replacement of lost animal habitats through the introduction of natural vegetation, occupying otherwise redundant roof space and providing a great opportunity to create new amenity space for people to use for recreation and increased overall wellbeing—a real benefit in dense urban spaces.

Alumasc BluRoof rainwater outlets may be used to drain the excess runoff that is not absorbed by a green roof. They do this in a controlled way, using specially designed flow restrictors: the attenuated stormwater is temporarily kept at roof level for controlled discharge — integral to the mitigation of flood risk. The number and aperture diameters of which are calculated individually per job, to reduce the rainwater discharge to a specific maximum rate advised by the designer. In this way, clients can be confident that an Alumasc BluRoof system can be trusted to provide a water management solution that is tailored bespoke to their needs.

With an Alumasc BluRoof, grey water can be attenuated at roof or basement level and re-used within the building, for applications such as air conditioning or toilets after filtering. This results in less water consumption by the building, and less rainwater discharge into sewer systems: both more environmentally friendly, and more economical. On large commercial schemes this can create client cost savings in the £100,000s per annum.

How often do you look up, beyond the ground floor office lobbies, shopfronts, or restaurants that line the high street?

There is an entire other world that exists above us, away from the buzz and bustle of the busy city; a new kind of urban jungle is being cultivated on our rooftops.

Across the world, there is ongoing intense increase in urban development and with it, city living and working. This demands of us an ever-greater understanding and conscientiousness of global climate change, and our part in it. As our population increases, we must develop sustainable and compact approaches to growth in order to avoid over-development, or further development into green belt land.

Green roofs can be a way of balancing our urban development by providing pockets of nature. If every city centre roof top were to go green, the impact upon our environment could be significant, in terms of the effect it could have on maintaining cleaner air quality, on reintroducing local wildlife and on providing places of calm and serenity in the middle of the hectic city.

They can even contribute towards the performance of a building, by providing insulation, energy balance and reduction of CO2 emissions, aiding SuDS with rainwater attenuation and surprisingly, even extending the life of roof waterproofing and therefore saving money. Facilities such as schools and office blocks can even make use of roof space for synthetic rooftop sports courts, conveniently encouraging people to make time for their own wellbeing and maximising BREEAM ratings for buildings.

Green roofs are not a new phenomenon, but the ways in which they are devised, designed, installed and maintained has developed. Modern green roof systems have been used around Europe for over 50 years and are commonplace throughout western Europe. Ranging from intensively vegetated (intensive) to extensively vegetated (extensive) to recreational, there are already many examples of living roofs in London including at Canary Wharf, Bishops Square, the Laban Centre, Deptford and Offord Street, Islington.

Blackdown Greenroofs originally specialised in the supply, installation and maintenance of roof planting systems with the main purpose of creating a natural habitat for wildlife in the urban environment. But as is the nature of nature, we’ve grown into a complete roof top, podium and balcony landscaping specialist.

Nurturing extensive knowledge and the sharpest skills when it comes to planting, we are uniquely equipped to advise our clients on the most appropriate green roof scheme for the project’s requirements, offering bespoke intensive green roof design, landscaping and installation. Whether seeking to fulfil biodiversity action plan requirements, optimise BREEAM ratings, or provide an aesthetic roof covering that stands out from the crowd, Blackdown Greenroofs can provide the optimum sustainable green roof design and tailored advice.

The real urban jungle is high above the paved forest floor, and is one viable way to contribute to a healthier, more sustainable future for our cities and our population.

Redcliff Quarter is a bustling new neighbourhood for Bristol, bringing together restaurants, a 4-star hotel, offices and apartments. The 600,000 sq ft development has an urban artisan design reflecting the area’s industrial heritage. The architecture includes wider pavements, rooftop and courtyard gardens, balconies and terraces, targeting BREEAM excellent ratings for the commercial buildings.

Derbigum Blue Roof System:

Alumasc’s Derbigum BluRoof is designed to alleviate flood risk by reducing and controlling the peak rate of discharge, in compliance with design requirements. This facilitates the detention of stormwater up to a prescribed maximum hydraulic head for subsequent controlled discharge over an elongated period.

The retention of stormwater in the green roof layers complements the detention of stormwater by the blue roof, providing valuable additional drainage capacity.

The Derbigum BluRoof system benefits from the combined expertise associated with Alumasc Roofing Systems and Harmer Engineered Drainage Systems; allowing a truly single source blue roof solution that is integral to a system of this nature. The Derbigum BluRoof system is fully BBA approved and Alumasc provide a service package that provides the client, specifier and end user with complete confidence in the integrity of the waterproofing and drainage solution.

Green Roof and Landscaping:

Blackdown Greenroofs installed a combination of extensive sedum green roofs, intensive green roofs, paving on terraces and podiums and over the Alumasc Derbigum BluRoof. Blackdown also installed the bespoke papyrus coloured powder coated planters, with integral hard wood seating. They were specifically designed to make the roof spaces a recreational asset to those living in the apartments. Planted with mixed herbaceous, shrubs and trees, the hard and soft landscaping areas provide the perfect place to relax.

Alumasc Roofing Systems provided design assistance throughout all architectural, structural and drainage engineering stages. The technical team worked closely with the Main Contractor providing further assistance throughout construction stages. Blackdown Greenroofs worked with both the Main Contractor directly as well as via Span Roofing who carried out the roofing installation sub-contractor package. Alumasc Roofing’s site monitoring technical teams carried out regular site visits to ensure compliance with the warranty and that codes of practice were observed through to completion.

One system supplier, one point of contact, one waterproofing installation team and Alumasc’s Blackdown Greenroofs provided a single source solution to the successful completion of the works thus limiting potential split responsibility.

For more information about Alumasc’s Derbigum BluRoof system click here or for technical advice, please call 03335 771 500.

Alumasc has provided the new R1 building, designed by Maki and Associates, with the Hydrotech MM6125 Structural Waterproofing system. R1 Kings Cross became the new home for a number of institutions founded by the Aga Khan, which aim to increase understanding of Islam in communities around the world.

For this project, Alumasc worked closely alongside Tilbury Contracts, an Alumasc Registered Contractor, who installed the specified system.

Alumasc assisted the project by supplying the tried and trusted Hydrotech MM6125 structural waterproofing system which has had zero product failures in over 50 years of use worldwide. Its unique formulation guarantees lifetime performance and it is manufactured using 30% post-consumer recycled material. Hydrotech is fully warranted, BBA accredited and has European Technical Approval ETA05/0152.

For Kings Cross R1, Alumasc’s system comprised Hydrotech with XPS insulation to insulate and prevent moisture from entering the roof. Hydrotech is a hot melt rubber bitumen membrane which is heated and combined with a polyester reinforcement and protection sheet to form a weatherproof layer. Through prevention of weathering, the roof will remain intact for a lifetime.

A truly unique finish was achieved with R1. The Hydrotech system was completed with decorative marble and stone, allowing for a contemporary appearance without any compromise to the performance of the system. This ornamental finish provides a clean and modern look to the North London building, the likes of which have been rarely installed before.

For more information on Alumasc’s high performance structural waterproofing systems click here or for technical advice, please call 03335 771 500.

Gelliswick Church in Wales VC School required a roofing system that would provide inhabitants with a reliable solution for the longevity of the building. Alumasc’s fully warranted Mastergold warm roof system was the ideal solution for the project.

The voluntary controlled primary school was formed following the decision to discontinue two nearby schools, the new school entity was established on 1st September 2017, with the school operating across the three existing sites. It was of the school’s interest to quickly relocate the students and staff from the other two sites to the new build, which opened in January 2018. This Mastergold system offers a quick and easy installation process without compromising the long-term performance of the waterproofing, it also requires minimal maintenance – another reason why the system was the ideal solution!

2,200m² of the Mastergold system was installed by the Alumasc Registered Contractor, Nautilus. The warm roof system included only 5 elements. Alumasc’s Self-Adhesive Primer was used to condition the metal deck, then, to encapsulate the deck from flames the Euroroof Dual Bond Vapour Control Layer was installed. The Dual Bond VCL has a self-adhesive backing to the underside and a thermofusible upper surface which enabled the PIR BGT insulation to be bonded directly to the membrane. To complete the warm roof system Mastergold Underlay was bonded to the BGT insulation which is torch receivable and the Mastergold Black Cap Sheet was then torched to the underlay providing a highly durable and effective solution.

The waterproofing is backed with an Alumasc 25-year system warranty, providing added peace of mind. The Euroroof Mastergold membrane offers high tensile strength and pliability and excellent resistance to puncture and UV degradation. The Euroroof Mastergold membrane is fully BBA approved and is tested for wind uplift and fire performance to meet with the current British Standards.

For further information about the Euroroof Mastergold system click here or contact our Technical Team on 03335 771 500

Material Store will provide 189 buy to rent apartments with residents’ parking and a communal garden.

The Old Vinyl Factory is a compelling project and was one of the largest regeneration projects in West London, home to a new community of more than 630 apartments with commercial and leisure facilities including restaurants, shops, cafes and bars.

The four ‘warehouse’ blocks of Material Store rise above a central podium area and surround an oasis of private patios and a large communal garden space. Each of the four main blocks were landscaped using a variety of Blackdown Green Roof products and finishes with the aim of providing an extended living space or ‘outdoor rooms’ for the inhabitants of the building.

The aim was to provide added recreational space and a greener environment for adults and children living there.

These areas include large green spaces that have been landscaped to provide a natural setting. These areas are made up of small trees and shrubs to give a natural effect and attract local wildlife. Blackdown’s intensive green roof system was ideal for these key requirements. An intensive roof – akin to a traditional ‘roof garden’ – often replicates the features and benefits of a domestic garden or city park; providing space for recreation and amenity. Applications can range from outdoor roof space at restaurants and office blocks to ground-level landscaping above subterranean car parks at shopping centres or residential developments.

Rob Beswick at B D Landscape Architects says:

“I visited site on Tuesday and was really impressed with the completed Material Store development – the podium landscape and roof terraces are well installed and great to see a project where the quality of the soft landscape hasn’t been compromised – so well done to your team!”

Green Roof Recreation and Play Area

Also incorporated was an area aimed at providing children with green space for them to play, in an otherwise highly built up area, thus improving their health and wellbeing for the future. Blackdown provided bespoke intensive planters containing a variety of wildflowers, sedums and shrubs. Paved areas, benches, decking and artificial lawns were also installed.

The inclusion of a podium play area was of interest as the play and recreational equipment was included within the initial design. This included large pebble seats, bears, large 3D resin play models and active play equipment.

These elements required a wide range of fixing and mounting solutions that were not initially designed for a podium deck. To provide adequate health and safety, gates and fencing were also installed, all of which, used specialist fixing methods to not compromise the waterproof integrity of the waterproofing membrane below.

To find out more about Alumasc’s green roof systems Click Here. Alternatively, if you would like to discuss any of our products or services with the team call 03335 771 500.

Constructed by CCG, The Ellerslie Road Development is a new build, high rise residential project located in the Yoker district of Glasgow on the northern bank of the River Clyde and is the tallest CLT building in Scotland.

Cross laminated timber or CLT is a structural, prefabricated panel used to form environmentally sustainable, walls, roofs and floors across a wide range of structures. The gluing of both longitudinal and transverse layers, which reduces the movement of the wood, means that CLT more than meets the standards required by modern building materials. CLT allows for quicker construction adding further sustainability compared with traditional construction methods.

Alumasc Exterior Building Products sets itself apart within the marketplace by providing a single source solution for the full envelope of any building project by combining the products and expertise of Alumasc’s various systems. These key benefits include unparalleled, single point technical assistance, extensive warranties and ongoing post-project support in relation to the full exterior of the project. Mast Architects specified Alumasc’s Roofing Systems, Façade (Walling) Systems, Rooflights and Harmer Drainage Outlets.

Flat Roof System:

With sustainability being a key part in the construction of Ellerslie Road, a Derbigum Olivine warm roof system was installed to provide a highly effective insulation for the roof areas. Derbigum Olivine cap sheet is coated with natural granules that neutralise CO2 found in rainwater upon contact. Olivine is also a fully BBA Certified solution which includes a durability statement which includes a service life of more than 40 years.

Alumasc provided full technical support throughout, particularly when providing the cut to falls BGT Polyisocyanurate insulation system to help provide added drainage efficiency.

The combination of these elements helps make the building more energy efficient by achieving a 0.13 U-value and improve the atmosphere on the outside. Alumasc Rooflights were also installed around the roof to allow the desired daylight to enter the building. 510m2 was installed by Alumasc Registered Contractors Hugh L.S. McConnell Ltd.

Walling/Facades:

Due to Yoker’s Cross-Laminated Timber (CLT) pre-fabricated construction, Alumasc Façade Systems’ Lightweight VBriQ Aricco was installed as it is specifically designed for use on timber frame constructions, providing a ventilated façade to protect the structure from the effects of moisture/water ingress. Again, the Alumasc technical team provided comprehensive support from start to finish. The ventilated cavity ensures that the timber substrate is kept dry in accordance with TRADA recommendations by allowing the building to breathe and prevents interstitial condensation.

The system provides aesthetically pleasing, UV resistant synthetic brick slips that can be replicated to almost any brick type – Sanctuary Scotland opted for Mid Brown, Traditional Brick Style (see pic). Furthermore, in keeping with CLT construction, VBriQ Aricco is quick to install (often upwards of 10 m2/day). With the inhabitants’ safety being of paramount importance this system provided the perfect solution having achieved an A2 fire-rating (A2-s1,d0). VBriQ Aricco is also backed up with BBA Certificate 15/5211. The system is also highly weather resistant in relation to wind driven rain, this was also key due to Ellerslie Road’s location alongside the River Clyde. 1100m2 was installed in total.

Benefits of Alumasc’s single source building envelope solution

Exploiting the combined expertise of Alumasc Roofing and Facade Systems allows a truly single source building envelope that we believe is integral to a system of this nature. Alumasc’s nationwide network of registered contractors combined with our own site monitoring team(s) ensures compliance with the warranty and codes of practice are observed through to completion.

The holistic approach to the design allowed for interfacing to be performed pre-contract allowing for installation on time, on budget and without compromise in terms of quality.

Split responsibility may result in the use of various trades and contractors, which in turn may lead to installation errors, damage to materials or negative warranty implications. The Alumasc Single Point Warranty limits this.

Alumasc’s single point warranties assure CCG and Sanctuary Scotland that if they require any further support in relation to this project in future it can be swiftly and efficiently provided from one single point of contact. This also includes details designed by Alumasc or any workmanship queries.

To find out more about Derbigum Olivine Click Here, for more Alumasc Facade Systems information Click Here. Alternatively to speak to our technical team call 03335 771 500.

The Brunswick Shopping Centre in London required a refurbishment to bring it into the modern era. This included providing the waterproofing solutions to all the main piazzas, walkways and podiums. With over 50 years zero product failures Hydrotech Structural Waterproofing was installed, this included a build up of XPS Inverted Insulation and the Hydrotech Hot Melt itself. Beneath these piazzas is a cinema and car park, therefore waterproofing integrity was vital. Hydrotech Hot Melt Waterproofing is fully BBA approved.

Above the Retail Units are situated residential dwellings of which the walkway areas also needed refurbishing. The existing deck was removed and replaced with a Derbigum Warm Roof consisting of Vapour Control Layer, Underlay and Derbigum Mineral Bituminous Cap Sheet. These walkways run above the whole length of the retail units below. Again, Derbigum Mineral Cap Sheet is fully BBA Approved.

For further information click here or call our Technical Team on (0) 3335 771 500

Q1. Can we purchase an Alumasc Blue Roof outlet without the waterproofing?

Alumasc has developed the BluRoof system that benefits from the combined expertise associated with Harmer Engineered Drainage Systems and Alumasc Roofing Systems. The result is that Alumasc is ideally positioned to offer a single-source solution, fully warranted waterproofing and sustainable drainage solution that is integral to a system of this kind.

We do not offer drainage attenuation design as a standalone package to be used in combination with any non-Alumasc product.

Q2. What are the typical flow rates that can be achieved using an Alumasc BluRoof?

BluRoof is an engineered drainage approach that addresses the individual project requirements. Blue Roofs are calculated to a whole rainfall series not just a single value, as intensity will change with time and therefore providing a default flow rate without analysis is not practical.

Q3. What information is required to provide a Blue Roof calculation?

The following key project parameters should be assessed to ensure that they are taken into consideration within our calculation.

1. The total size of the applicable areas in m², and if any other areas are draining onto them, the size of them also. Roof plan
    preferably in .dwg format would be required if the size of area was not advised.

2. The plan size of the applicable void former area in m², if less than the total plan area.

3. Are there any height constraints that would restrict the depth of void former that can be accommodated within the
    proposed assembly.

4. Are there any project targets identified for the Blue Roof to achieve, for example:
    – A particular peak run off rate in litres per second (l/s).
    – The detention volume of water (m³) to be attenuated per roof area.
    – A particular % reduction in the site peak run-off rate

Alumasc offer a free Blue Roof design service and all enquiries should be sent to technical@alumascroofing.com

Q1. What is the fire rating of Alumasc Extruded Polystyrene?

Fire performance is declared Euroclass E under EN 13501-1. A flame retardant additive is also present that makes it capable to resist, for a short period of time, a small flame attack without substantial flame spread.

When ballasted with either 20/40mm grade aggregate (minimum depth of 50 mm) or fully-supported cast stone or mineral slabs of at least 40mm thickness, the roof may be considered to be of designation AA (low vulnerability in Scotland) and so is unrestricted by the national Building Regulations.

Q2. Are there any non-combustible insulations compatible with Alumasc roofing systems?

Two insulations rated separately as ‘non-combustible’ (i.e. class A1 to EN13501) are Foamglas and Rockwool Multi-Fix Dual Density Mineral Wool. Both products are compatible and available as a system within the Alumasc product offer as part of a warm roof assembly.

For further information about Alumasc’s insulations contact our technical team on 03335 771 500