Modular can improve construction quality.
Constructing units in a controlled, dry environment, with kiln dried timber, with floors, walls and ceilings constructed on flat stable surfaces, results in a product that exceeds the tolerances found in most conventionally built housing. Modular construction also helps minimize mold and other water damage issues later on by construction in a dry factory.
A conventionally constructed project (image bottom right) exposes materials to weather. Accuracy, plumb and level are more at risk on an on-site project due to exposure and material drying on-site.
Structurally, modular construction is designed for transportation and lifting, increasing the quality of the structure. This results in modular construction being structurally stronger than conventional site-built construction.
The 1.202% effect, as coined in the 2007 MIT modular study makes modular stronger than conventional site built due to redundancy. The MIT report states: “A modular structure has a certain inherent strength superiority to a traditional site-built home due to the fact that each module is a self-supporting and independent structure.” Also, quality is increased in modular construction by the practice of gluing and screwing drywall and sheathing, rather than just attaching with screws alone, as is established practice in conventional site-built construction.