External wall insulation systems - StoTherm

StoTherm is a range of external wall insulation systems (EWIS), also known as externally thermal insulating composite systems (ETICs) or more colloquially known as 'insulated render', features a variety of insulation materials, reinforcement layers and a vast range of surface finish options. These include highly customisable through-tinted plaster or renders, as well as alternative finishing materials such as resin or clay brick slips, making it possible to create functional, durable and beautiful facades.

Products and systems vary from location to location due to local building regulations and standards. We strongly advise you to contact your local expert who will be happy to consult you on standards and approval.

Advantages of external wall insulation systems

• Cost-effective low carbon architecture for new build or renovation projects
• Improved aesthetics with multiple surface finish options
• Increase lifespan of building fabric by protecting it from the elements
• Variable insulation thickness up to Passivhaus standards
• Lower heating and cooling energy consumption
• Maximise space inside by installing insulation on the outside
• Minimise thermal bridging, reducing condensation risk

Benefits of StoTherm

• Multiple insulation options, including non-combustible materials
• Multiple finish options & materials, including intense, dark colour shades
• High resistance to mechanical stress & cracking
• Up to 120 Joules of impact resistance possible
• High resistance to microorganisms (algae and fungi)
• High weather-resistance
• Permeable to water vapour and CO2
• Cement-free, ready-to-use system components with minimal waste

Choose from multiple insulation material options

The Sto systems can be designed with an appropriate thickness of insulation to meet any project requirement, including compliance with Passivhaus standards. The systems are either bonded or mechanically fixed to a suitable load-bearing substrate, either on new buildings or for energetic retrofit and thermal upgrading of existing buildings.

Product systems and the choice of insulation vary from location to location due to local building regulations and standards. We strongly advise you to contact your local expert who will be happy to consult you on standards and approval.

Why insulate the outside of a building? Find out more

Surface finishes for a distinctive first impression

Performance and aesthetics are essential for the long-term success of a building. Sto offers a vast range of surface materials for facade designs including:

• cement-free acrylic-based renders
• silicone- & silicate-based renders
• mineral-based renders
• prefabricated render tiles
• 3D sculpted facade profiles & panels
• metal, concrete, wood or brick impression render
• brick slip & ceramic tile claddings

Find out more about our facade surface finishes

Enhanced performance with innovative coatings & additives

Minimise the long-term impact of extreme weather, moisture, algae and fungus on building facades with Sto's innovative coatings, paints and additives. Depending on the building requirements and local climate conditions, facade paints and coatings can help keep your facade looking its best for many years:

• StoColor Dryonic - protect from algae & fungus
• StoColor Photosan - break down airborne pollutants
• StoColor X-Black - prevent solar-related cracking & discolouring
• StoColor Lotusan - hydrophobic surface to keep the surface cleaner

Find out more about Sto's Intelligent Technology facade finishes

Flexible reinforcement layers for high crack and impact resistance

Reinforcement materials are added between the insulation and the surface finish, designed to improve impact resistance and to absorb thermal stresses caused by temperature fluctuations. This prevents crack formation and therefore protects against the ingress of water.

Sto offers a choice of cement-free or cementitious reinforcement layers, creating an impact resistance of up to 120 joules with the appropriate system build-up.

Technical support & design visualisation

At our global locations and using state of the art U-value or dew point calculation tools, we are able to advise design and construction professionals on the anticipated effects of applying insulation at your locality, in your individual climatic conditions, regardless of hot and humid, cold or wet. This allows us to suggest the most appropriate solution suitable for your building. Sto also offers material advice and a visual design service to housing authorities and construction partners to enable them to visualise the improvements being suggested.

Discuss your project with a local Sto representative