Where the work happens
Prefab moves some work into advance preparation and production. Traditional construction involves more work on site. This affects scheduling, logistics and when decisions must be final.
What suits your situation
- How accessible is the house for transport and lifting?
- How unusual are the shape, dimensions and connections?
- How much space is available on site?
- When must materials be chosen?
- Which work remains on site with either method?
Compare the same scope
Quotations should describe the same performance and finish. A prefab shell and a fully finished traditional extension are not directly comparable. Consider foundations, openings, connections and handover as well.
Compare methods on equal terms
Give both suppliers the same plan, finish requirements and photographs. Ask how much work remains inside and when the facade will be opened. Discuss material storage and whether you can stay at home. A difference in installation time is meaningful only when the preparation and finishing outside that period are clear.