The back kitchen extension is probably Malaysia's most common structural renovation — and the one with the widest spread between quotes. One contractor says RM45,000, another says RM85,000, and the drawings look identical. Here is where the money really goes on a typical 300 sq ft wet kitchen extension, so you can see which quote is missing what.
The honest breakdown (typical RM80,000 project)
- Drawings, engineering and council submission — about 8%. Architect or submitting person fees, structural design and authority charges. The cheap quote omits this line entirely; the extension is then illegal.
- Foundations and structure — about 30%. Excavation, footings or micro-piling, reinforced concrete columns, beams and slab, plus brickwork. Soil condition moves this line more than anything else on the page.
- Roofing and waterproofing — about 15%. Metal deck or tiled roof, insulation, gutters, and the critical waterproofed junction where the new roof meets the existing wall — the spot every cheap extension eventually leaks.
- Plumbing and electrical — about 12%. New sink runs, gas point, drainage tie-ins, extra circuits and lighting. The number climbs if the existing DB has no spare capacity.
- Floors, walls and doors — about 15%. Screed and tiling, plastering and paint, plus the aluminium sliding door that usually separates wet and dry kitchens.
- Cabinetry and worktops — about 15%. The most personal line: melamine keeps it modest, full quartz and soft-close everything pushes it well past.
- Preliminaries and cleanup — about 5%. Hoarding, debris disposal, protection of the existing house, final cleaning. Invisible in photos, mandatory in reality.
How the RM45,000 quote gets to RM45,000
Almost always the same four omissions: no council submission, no soil consideration in the footing design, single-layer roofing with no junction detail, and "cabinetry by owner". Add those back honestly and the cheap quote lands within a few thousand ringgit of the expensive one — except now the surprises arrive mid-project, when you have no negotiating position.
Three questions that expose a padded or hollow quote
- "Which line covers the council submission, and who is the submitting person?"
- "What is the footing design based on — and what happens to the price if the soil is soft?"
- "Show me the detail where the new roof meets my existing wall."
A competent contractor answers all three without flinching. The other kind changes the subject to how fast they can start.
Thinking about your own extension? Read what our structural crews handle on the rebuild and extension works page, or book a feasibility visit — the honest number costs nothing.