Mabati Gauge Explained: What the Numbers Really Mean
Mabati gauge is the thickness of the steel sheet. The lower the number, the thicker and stronger the sheet. Gauge 28 is thicker than gauge 30, which is thicker than gauge 32. Thicker sheets cost more and last longer. Below is the thickness table and how to confirm the gauge you pay for is the gauge you get.
Gauge is the single most misunderstood word in buying mabati, and the one most often used to overcharge or short-change a buyer. Get it right and you cannot be easily cheated. Here is the plain explanation.
What gauge actually means
Gauge is the thickness of the steel sheet. Counter-intuitively, the lower the number, the thicker the steel. So gauge 28 is thicker than gauge 30, which is thicker than gauge 32. Thicker steel costs more, resists dents better, is quieter in the rain and lasts longer.
The thickness table
| Gauge | Approx steel thickness | Typical use |
|---|---|---|
| Gauge 32 | ~0.20mm | Budget, stores, temporary structures |
| Gauge 30 | ~0.30mm | The standard house roofing gauge |
| Gauge 28 | ~0.40mm | Permanent homes, coastal and high-rust areas |
Exact thickness varies slightly by manufacturer and coating, but these are the figures to expect and to ask for in writing.
What each gauge costs
For box profile this month, gauge 30 runs KSh 480 to 650 per metre and gauge 28 runs KSh 720 to 800 per metre. Corrugated is cheaper in every gauge. The jump from G30 to G28 typically adds KSh 150 to 200 per metre, which on a 3-bedroom roof works out to roughly KSh 30,000 to 50,000. See gauge 30 prices and gauge 28 prices for the full breakdown.
The gauge trick to watch for
The most common mabati scam is selling gauge 32 as gauge 30. The difference of a tenth of a millimetre is nearly impossible to judge by eye, so a thin sheet can be passed off as a thicker one at a healthy markup. Protect yourself three ways:
- Ask for the gauge and steel thickness in writing before you pay.
- Check the price against this month’s verified range. A gauge-30 price far below the range is a red flag for thinner steel.
- Buy from a factory with a claimed, reviewed Google profile so there is accountability if the delivered sheet is not what was agreed.
So which gauge should you buy?
For most homes, gauge 30 is the right answer: strong enough, widely available and fairly priced. Choose gauge 28 when the roof needs to last decades without attention, when the house is near the coast or in a high-rust area, or when quietness in heavy rain matters to you. Choose gauge 32 only for stores, temporary structures or the tightest budgets, and expect a shorter life. See the full G28 vs G30 comparison to decide.