The GBE System® can contribute to optimising construction costs, simplifying project interfaces and maintaining a significant part of the value chain within the structural works package. Its cast-in-place principle also allows local contractors to use their existing reinforced-concrete skills.
Cost optimisation
The wall combines structural concrete, integrated insulation and the external concrete finish within a single construction principle, which can simplify the overall cost structure of the façade.
Local construction
Walls are cast directly on site by the structural contractor, supporting the use of local labour, concrete supply chains and established construction skills.
Simplified scheduling
Integrating the insulation during structural works can reduce the number of subsequent façade operations and simplify coordination between separate trades.
Supporting local construction expertise
The GBE System® is based primarily on materials and construction techniques commonly available within the concrete sector. Concrete production, reinforcement, formwork and wall construction can therefore rely extensively on local supply chains and local contractors.
Because the walls are produced directly on site rather than supplied as complete prefabricated façade panels, a significant part of the construction work remains within the structural contractor’s scope. This enables companies to make direct use of their own formwork, reinforcement and concrete-placement expertise.
The approach can therefore contribute to maintaining local construction skills and employment while reducing dependence on specialised off-site façade manufacturing.
Durability and whole-life cost
The economic performance of a building should be considered over its entire service life and not only through its initial construction cost. Concrete provides a robust external surface with high resistance to normal weather exposure and mechanical stresses.
In the GBE System®, the insulation is protected between the two concrete leaves, reducing its direct exposure to weather and accidental damage. This configuration can help limit maintenance operations associated with the external thermal envelope over time.
Since the façade is cast in place rather than assembled from prefabricated panels, there is also no repetition of panel-to-panel joints across the façade, apart from the construction, movement or expansion joints required by the project and applicable standards.
Construction programme and trade coordination
With the GBE System®, the insulation is installed during the structural works phase. This can reduce the amount of façade work to be carried out after completion of the main structure and can simplify coordination between structural, insulation and external-finish trades.
Once the concrete walls are completed and the building is sufficiently enclosed, internal works can also progress without waiting for a separate external insulation package to be installed over the entire façade.
This integration can help reduce interfaces within the construction programme and limit the exposure of certain façade operations to adverse weather conditions. The actual time saving nevertheless depends on the organisation, geometry and construction sequence of each project.
Project-specific economic studies
The economic performance of the GBE System® depends on the wall configuration, project geometry, concrete and insulation specifications, reinforcement requirements, architectural finish and construction method.
GBE can therefore carry out project-specific economic studies to compare the cost of GBE walls with alternative façade solutions and to identify opportunities for optimisation at an early design or tender stage.
Cost and programme benefits are project-specific. They should be assessed using the actual wall areas, structural requirements, façade finishes, labour conditions and construction sequence applicable to each project.
Costing guidance
A practical benchmark for estimating GBE installation labour
For a contractor using the GBE System for the first time, labour requirements can be estimated using a simple approach derived from extensive site experience: start with the labour ratio the contractor would normally allow for constructing the same wall as a conventional cast-in-place concrete wall, then add approximately 0.50 labour-hours per m² of gross formwork area.
The starting ratio should reflect the actual wall to be constructed. It should therefore already account for the wall’s inherent complexity: number of openings, geometry, architectural features and profiles, form liners, specified concrete finish, exposed concrete, concrete intended to receive a stain or other finish, and any other requirement that affects formwork operations or the level of care required to achieve the specified architectural result.
GBE labour ratio ≈ equivalent concrete wall labour ratio
0.50 h/m²
Measurement basis: all ratios are expressed in labour-hours per m² of gross formwork area, with openings not deducted. The reference area therefore corresponds to the gross wall area, including door and window openings.
01
Establish the baseline concrete-wall ratio
Use the labour ratio the contractor would normally apply to the reference concrete wall, taking account of its geometry, openings, architectural features, form liners and specified surface finish. The ratio is expressed in h/m² of gross formwork area, with openings not deducted.
02
Add the labour specific to the GBE System
Add approximately 0.50 h/m² of gross formwork area for installing the insulation boards and GBE connectors, fixing the reinforcement for the external concrete leaf and carrying out the additional operations associated with placing the concrete for the second leaf.
03
Adjust only where the project requires it
Unusual or particularly complex configurations may require the allowance to be adjusted. For typical projects, this method provides a practical preliminary costing benchmark for contractors who are not yet familiar with the GBE System.
