The Transportability of Panels and Modular Homes

Modular housing can be tested during the development stage for both structural and environmental performance. There are a variety of different testing methods that will prove modules or panels are fit for purpose and will meet the performance standards of building regulations when constructed in the factory. However, what is often unknown or not considered, is the effects of transporting panels or modules to site.

Inadequately stored panels can deteriorate if unprotected due to weather or fail when put under load due to poor storage and transportation techniques.

Transportation can also effect windows and doors with stresses acting at the corners causing cracking or damage to the window glass or casing.

The construction stage has the additional problem of requiring the incorporation of suitable panel lifting points. The lifting points need to enable the use of safe lifting techniques and should not impact on the way the panels join to form the building. Poor lifting techniques can put too much stress into the frame and cause plastic deformation which is not visual but will ultimately cause failure. Furthermore, panels can be damaged when placing them down, particularly if the load is not centred and the panel lands on one corner or partial edge first.

This can cause extensive damage and prevent panels being bolted down to the foundations correctly or lining up with other panels or modules. Depending on the extent of damage, repairs may be required or shims added; this can result in areas that are not waterproof or structurally sound.

At an added cost, supplementary bracing or increased material thickness can be used to help the transportation and lifting processes, but these are often redundant when the panel is installed and in use.

The transporting, storage and installation (TSI) techniques also impact on the costs of the overall build. Any savings made during the construction process can be factored into the project cost and give a cost advantage in the initial tender process.

Panels or modules can be damaged during any of the TSI stages; this can have a large impact on the end-use of buildings. Damage sustained cannot always be seen by the naked eye, e.g. joints can open up behind sheathing or plaster boards which can have a bearing on thermal and acoustic performance, and in extreme cases, may affect weather tightness.

The impact of the transport and installation processes can be assessed using different techniques. During the lifting, transportation and construction stages, the live measurement of the stresses and strains being generated in the frame or cladding can be taken. Ultrasonics, air leakage testing and thermal imaging can be used to benchmark the panel or module performance in the factory and at the finished construction phase. These procedures assess any deterioration and can prove the performance in relation to the requirements of the building regulations.

A factory-built modular system creates a consistent and quality product that is not always found in traditional build. The success of a factory-built modular building is dependent on it arriving at site and being erected in the same condition as it left the factory.