🇲🇱 Mali · DQE / DPGF · Work section
Substructure & foundations in a Mali bill of quantities
In Mali, the substructure section of a Bill of Quantities (Devis Quantitatif Estimatif) (Devis Quantitatif Estimatif (DQE) / DPGF) is measured to DQE / DPGF (French practice). It covers 7 principal groups of work — site clearance and removal of topsoil through to ground floor slab and any thickenings — and is headed in the bill as "LOT 3 — SUBSTRUCTURE & FOUNDATIONS".
Substructure & foundations is one of the sections every Bill of Quantities (Devis Quantitatif Estimatif) (Devis Quantitatif Estimatif (DQE) / DPGF) in Mali is built from. This page sets out what belongs in it, the unit each item is measured in under DQE / DPGF (French practice), the local conventions that change the quantities here, and a worked example for a 150 m² house — plus the errors in this section that actually cost money on site.
What this section covers
- Site clearance and removal of topsoil
- Excavation to reduce levels and to foundation trenches
- Earthwork support and keeping excavations free of water
- Disposal of excavated material, on site or off
- Mass or reinforced concrete footings
- Hardcore filling, blinding and damp-proof membrane
- Ground floor slab and any thickenings
How each item is measured
| Item | Unit | Measurement rule |
|---|---|---|
| Excavation | m³ | Measured net from existing ground level to the underside of the concrete. Working space is a separate item, not an addition to the volume. |
| Disposal | m³ | Bulk excavated volume, with an allowance for bulking — spoil occupies more once dug than it did in the ground. |
| Concrete in footings | m³ | Measured net; no deduction for reinforcement or for voids under about 0.05 m³. |
| Hardcore filling | m³ or m² | Measured to the compacted thickness. Loose delivered volume is materially greater. |
| Damp-proof membrane | m² | Net area covered; laps and turn-ups are deemed included in the rate. |
| Ground floor slab | m³ or m² | Measured on the net area, stating the thickness. |
Local conventions in Mali
- —Foundations here are conventionally strip type, taken 0.6 m deep and 400 mm wide.
- —Footing concrete is normally a 1:2:4 mix, with 50 mm blinding beneath and 150 mm of hardcore under the slab.
- —A damp-proof course and membrane are standard practice and must be measured — leaving them out is the most expensive omission in this section.
Worked example — 150 m² house in Mali
Quantities for this section on a representative single-storey house, computed from Mali construction conventions. Rates are deliberately not shown: they move constantly and are priced against your own drawings.
| Description | Qty | Unit |
|---|---|---|
Trench excavation 50 m perimeter × 0.4 m wide × 0.6 m deep | 12 | m³ |
Mass concrete footings 225 mm thick strip footing, mix 1:2:4 | 4.5 | m³ |
Hardcore filling 150 mm bed under the ground slab | 22.5 | m³ |
Blinding concrete 50 mm blinding over hardcore | 7.5 | m³ |
Ground floor slab concrete 100 mm slab over 150 m² | 15 | m³ |
Damp-proof course / membrane Slab area plus 10% laps | 165 | m² |
What goes wrong in this section
- —Substructure is the section most often priced from the drawing rather than from the ground. A trial pit that finds soft material below founding level re-prices the whole section.
- —Trench depth and concrete thickness are different numbers. Measuring concrete to the full trench depth over-orders by a third or more.
- —Disposal is routinely forgotten. On a constrained urban site, carting spoil away can cost more than digging it.
Get every section measured, not just this one
Upload your dimensioned drawings and get a complete bill of quantities (devis quantitatif estimatif) in the DQE / DPGF format, priced in XOF (CFA), with every rate source-cited.
Generate my Mali BoQSubstructure & foundations — frequently asked
What goes into the substructure section of a bill of quantities in Mali?
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Site clearance and removal of topsoil; Excavation to reduce levels and to foundation trenches; Earthwork support and keeping excavations free of water; Disposal of excavated material, on site or off; and 3 further groups of work. Under DQE / DPGF each is described, measured in its own unit, and priced separately so the total is auditable line by line.
What units is substructure & foundations measured in?
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Excavation in m³, Disposal in m³, Concrete in footings in m³, Hardcore filling in m³ or m². Getting the unit right matters more than getting the quantity precisely right — a contractor can adjust a quantity, but cannot price an item measured in the wrong unit at all.
How is substructure & foundations different in Mali from elsewhere?
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Foundations here are conventionally strip type, taken 0.6 m deep and 400 mm wide.
What is the most common costly mistake in this section?
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Substructure is the section most often priced from the drawing rather than from the ground. A trial pit that finds soft material below founding level re-prices the whole section.
How do I get this section measured for my own project?
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Upload your dimensioned drawings to Enormous Buildings. The bill is produced in the DQE / DPGF format, grouped by section with substructure & foundations priced in XOF (CFA), and every unit rate carries a source so a Mali quantity surveyor can check it.