Insulated – What is EWI?
External wall insulation (EWI) is insulation that is adhesively & mechanically fixed to the exterior substrate of a building, and then rendered to give a protective finish. This is an
innovative solution which improves structural and thermal performance as well as the overall aesthetics.
What are the benefits of external wall insulation?
- Savings on heating bills – reducing heat loss through walls can save up to 45%
- Improved comfort – a warm, dry building without condensation or damp
- Enhanced appearance – through our high-quality external finishes
- Increased property value – a more energy efficient building with an attractive facade
- Low maintenance – the highly durable render is rain and UV-proof
- Help the environment – reducing heat loss reduces the buildings carbon footprint
- Low impact project – no need to vacate the building as all the work takes place outside
- No effect on internal space – all the insulation is on the outside walls
Case Studies
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Project Wellesley - Insulated Render
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Blogs
The main benefit of rainscreen cladding systems is that it protects the structure of the building, whether it’s a steel frame or masonry based system, from the elements and specifically rainwater. It does this because the cladding panels form a barrier to rainwater, preventing it from penetrating across the rear ventilated cavity and reaching the exterior wall of the building. This process is helped by air continually circulated up through the ventilated cavity, driving any moisture that penetrates between the panels, upwards and out at soffit level before it reaches the building structure.
Keeping a building dry in this way provides it with a number of performance benefits including better thermal efficiency. For instance, keeping the external wall dry retains its energy efficiency. Conversely, a wall that becomes wet loses more energy because water conducts heat energy from inside the building. Aside from this advantage of rear ventilated cladding, keeping the underlying structure dry means less maintenance as there are fewer incidents of rust or corrosion on metalwork or spalling of masonry elements.
Rear ventilated cladding systems offer another significant benefit in that they are relatively lightweight when compared to conventional masonry builds. The use of lightweight materials like aluminium in facade panels therefore means less loading on the underlying building structure. This allows savings to be made on foundations and internal supporting walls, both of which tend to be made from high embodied energy materials like masonry. Architects and designers have long understood that reducing the need for internal supporting walls creates lighter, brighter interiors, a fact that is particularly valuable to landlords looking to maximise rental space and create a desirable, naturally-lit interior ambience.
Rainscreen cladding can also impact significantly on a building’s ongoing maintenance costs. Without rainscreen cladding on exterior elevations, buildings made of porous material such as cement render are exposed to the elements and the deterioration process can happen quickly. One of the biggest benefits of specifying rainscreen cladding is the almost limitless possibilities it provides in terms of aesthetics and making a visual impact. In addition, modern rainscreen cladding systems allow for individual panels to be removed, giving maintenance teams easy access to services. This ease of access means that upgrades or repairs to building services can be done cost effectively and with minimum disruption to occupiers.
Adding rainscreen cladding to the exterior of an existing building is a low-cost way of improving its thermal performance, without any loss of internal floor space. In an over clad situation, insulation is fixed to the external wall of the building before over cladding with a rainscreen system. Over cladding is also an excellent way of modernising a tired looking building envelope that may be structurally sound, but poorly insulated and unsightly. Over cladding an existing building, rather than demolition and new-build, is also much less carbon intensive, for example, having to remove materials from site takes a huge amount of resources as well as being disruptive for local residents.
Modern rainscreen cladding systems are lightweight and strong and because of that, they support the creation of innovative designs that appear to defy gravity. Rainscreen cladding system can help designers deliver visionary and innovative developments that really make your building distinctly different. Talk to us at Rendserve to understand your options and what we can do for your building.
A tired looking, stained, cracked or delaminated render system to the façade of any building is not a good advert for a client, especially on public buildings including Hotels, Schools, Hospitals, universities etc. An unmaintained building suggests lack of care or maintenance and will ultimately impact on the long-term performance of the building.
Cracked, damaged, discoloured render systems can easily be restored and repaired using modern materials and techniques. Often, the cause of the problem can be determined and addressed during the rectification works.
A process of surface preparation, renovation and recoating using high specification nano-quartz renders and paints will provide a long term, self-cleaning solution and bring the building back to life. There is even the opportunity to bring new and bolder colours into the mix and completely change the aesthetics of your building. The High spec Nano Quartz technology in modern renders have a self-cleaning element keeping your building looking fresh and clean for years to come. The same can be said for tired looking existing masonry surfaces be it brickwork or block, a newly applied render coat can totally transform the appearance of any building as well as providing protection of the building substrate for many years to come.
Older projects outside of their original warranty may be looking tired or cracked. Once the surface of the render fails, it is only a matter of time before delamination begins to occur. The cyclical freeze/thaw process can blow render in just a very short period of time with the potential for water ingress and internal damage.
Many early render projects may have been installed using a cheaper, less high spec acrylic top coat which had very little in the way of fungicide in its composition and now, buildings are showing signs of moss & algae growth. This is also true of inner city areas where higher pollutants in the atmosphere may have shown as discoloration to the building exterior.
Failed render and insulated render systems can be extremely hazardous environments due to the high risk of delamination. Early intervention is essential in protecting not just the public, but the integrity of the building too. Could you afford for a claim to be brought against you for potential claims where delaminated render has caused injury to the public? See link http://www.bre.co.uk/pdf/facademaintenance.pdf
Laminated Rainscreen Cladding panels can quickly lose their lustre if not maintained. The matting effect not only spoils the appearance of the building, the accumulation of surface soiling in a constant process and will only get worse.
Rendserve Ltd are accredited with ISO14001 Environmental Standard as wells as ISO9001. We are certified with CHAS, Constructionline and Achilles. Our insurance levels are £10m Public and Employers Liability and £5m Professional Indemnity. All Management are trained to at least SMSTS or SSS and operatives are CSCS, IPAF and PASMA Trained.
For informed and helpful assistance please contact a member of our hugely experienced team who will be able to talk you through the options and provide a free, no obligation, highly competitive quotation and start you on your first step in bringing your building or home back to a condition you can be proud of.
