When should you consider using modular construction?
A modular approach benefits most from being considered early in the design process. It is more difficult to swap over to an off-site solution if the designs are already finalised. Although we have worked on projects where bathroom pods have been introduced even after the contractor has been handed the site, this is not ideal as some of the benefit of using this methodology is then lost.
The diagram below represents the main areas to consider when determining whether to use off-site construction methods:
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Is there repetition within the building?
Will a light weight structure create a cost saving?
Constraints specific to the project
Will a short build time improve the NPV of the revenue stream?
Schools, student residences and hotels are types of buildings where the completion date has a major impact on the revenue stream. It is hard to think of a project where the completion date doesn't impact the viability of the project, but there are certainly some projects where this is more critical than others.
Hotels, hospitals and student residences typically have a limited number of variations in the floor plans but also a large number of units in each project. These would be ideal candidates for modular construction methods. Conversely, a single residential home or a boutique hotel with many variations to the room layouts would not reap the benefits of off-site construction.
How expensive is the land?
If construction can continue with limited disruption from builder's holidays, weather, or any other seasonal impacts, the benefits of off-site construction will not be valued.
How accessible is the project site?
Are there risks of delay?
The more expensive the land, the greater the holding cost and thus the greater the value of a shortened project timeline.
Modular construction can provide a real solution where there are restrictions on the times when building activities can occur or where site access places pressure on receiving multiple deliveries of materials (like readymix cement, bricks, windows etc all from separate suppliers and thus separate deliveries)
Are skills available at the project site?
Projects requiring certain skills that are not available near the geographic location of the project can benefit from off-site construction with its shortened installation timeframe (of skills are brought in) or removal of the skilled labour requirement completely from the project location to a manufacturing location with access to the necessary skills.
Modular bathrooms and structural room modules can be up to two thirds lighter than conventional alternatives. This can dramatically change the foundation requirements (and hence the related cost) or afford more levels to be added to an existing structure than would otherwise be possible.
Here is an opportunity only available to light weight modular construction
Due to the light-weight nature of modular components, old retail space on traditional "main roads" can be converted into mixed use developments by adding apartments on top of the existing structure without needing to modify the existing structure to accommodate the additional levels. All this can occur with limited disruption to the retail space, thus preventing any adverse affects to the revenue stream.
Click to go to next article: How much time can modular save?