External Wall Insulation (EWI) is made up of several different materials that work together as a complete system. From insulation boards and adhesive to reinforcing mesh, primer and finishing render, each component has a specific role within the overall wall build-up.
Choosing EWI materials is therefore about more than selecting an insulation board. The products need to be suitable for the building, compatible with each other and appropriate for the intended application.
At Infinity PM, we supply a range of EWI materials, including insulation boards, basecoats, reinforcing mesh, fixings, profiles, primers and render products for UK trade projects.
What Materials Are Used in an EWI System?
A typical EWI build-up can include:
- Insulation boards
- Adhesive or bonding products
- Mechanical insulation fixings
- Reinforcing basecoat
- Fibreglass reinforcing mesh
- Corner and stop profiles
- Primer
- Final render
The exact materials required will depend on the insulation system, substrate, building requirements and manufacturer's specification.
EPS Insulation Boards
EPS is a commonly used insulation material within EWI systems. It can be available in different specifications, including standard white EPS and graphite EPS.
The required board type and thickness should be selected according to the project requirements and the relevant system specification.
At Infinity PM, EPS insulation boards are available alongside the other materials needed to build an EWI system.
Adhesive and Basecoat
Adhesive is used to help secure insulation boards to the wall substrate, while the basecoat forms an important part of the reinforced layer.
Some EWI products are designed to perform more than one function, depending on the system. For example, products such as ATLAS Grawis U and ATLAS Hoter U are used with insulation materials and can also be used for the reinforced layer.
Always check the product's technical information to confirm the intended application and compatibility.
Mechanical Insulation Fixings
Mechanical fixings provide additional attachment for insulation boards as part of an EWI system.
The appropriate fixing depends on factors such as the insulation type, board thickness and substrate. Fixing selection should therefore be based on the system specification rather than simply choosing a product based on length or price.
Infinity PM supplies insulation fixings, including products suitable for use within EWI applications.
Reinforcing Mesh
Reinforcing mesh is incorporated into the basecoat layer before the final render is applied.
Fibreglass mesh helps reinforce the basecoat and forms an important part of the EWI build-up. It needs to be installed correctly and should be compatible with the basecoat and wider system.
The mesh is particularly important around areas where additional detailing or reinforcement may be required, such as corners and openings.
EWI Profiles
Profiles are smaller components, but they can play an important role in completing an EWI installation.
Depending on the project, profiles can include:
- Corner beads
- Stop beads
- Base tracks
- Window and door profiles
- Other edge and detailing profiles
Some profiles incorporate reinforcing mesh to help integrate the detail into the reinforced layer.
Choosing the correct profile for each part of the installation can help achieve a clean and properly detailed finish.
Primer for External Render
Primer is generally applied before the final render where required by the system.
Its purpose is to prepare the underlying surface for the selected finishing coat. The correct primer should be chosen according to the render and system requirements.
For example, ATLAS Cerplast Priming Mass is designed for use with selected thin-coat render applications.
It is important not to treat primer as a universal product. Compatibility with the finishing render should always be checked.
Choosing the Final Render
The final render is the visible external finish of the EWI system.
Different render products can provide different finishes and properties. Options can include silicone, silicone-based and other thin-coat render systems, depending on the manufacturer's range and the project specification.
Infinity PM supplies ATLAS render products for suitable EWI and external façade applications, including products such as ATLAS Gemini RS 1.5mm.
The final render should be selected together with the appropriate primer and compatible basecoat system.
Why Compatibility Matters
An EWI system is made up of multiple layers, so choosing products individually without considering the complete build-up can create problems.
For example, the insulation board, adhesive, basecoat, reinforcing mesh, primer and final render should be suitable for use together.
Before ordering materials, check:
- The wall substrate
- Insulation type and thickness
- Adhesive requirements
- Mechanical fixing requirements
- Reinforcing mesh specification
- Required profiles
- Compatible primer
- Final render type
- Manufacturer's installation guidance
This approach helps ensure that the materials selected are appropriate for the intended EWI application.
Planning an EWI Materials List
A useful materials list should cover the complete installation rather than just the main insulation boards.
Depending on the project, you may need:
Insulation: EPS or another specified insulation material.
Fixings: Mechanical fixings suitable for the insulation and substrate.
Reinforcement: Basecoat and fibreglass reinforcing mesh.
Profiles: Corner beads, stop beads, base tracks and other required details.
Preparation: Primer suitable for the selected finishing system.
Finish: Compatible external render.
Planning these components together can make ordering easier and reduce the chance of missing important materials.
EWI Materials from Infinity PM
Infinity PM supplies a range of External Wall Insulation materials for trade projects, including EPS insulation boards, basecoats, reinforcing mesh, insulation fixings, profiles, primers and ATLAS render products.
Whether you are preparing an EWI materials list or looking for individual components, it is important to select products based on the complete system and the requirements of the project.
Explore EWI materials at Infinity PM and find the components you need for your external wall insulation project.