In brief
- A provisional sum is an allowance, not a price, so the winning bidder may never have priced the supervision and skill the actual work needs.
- The gap shows up at instruction stage: the contractor sends whoever is free, and the client has no tested record to challenge it.
- Close it by describing method, testing and supervision in the instruction, not by trusting the bid total.
Contents
A provisional sum does not buy labour, testing or supervision. It only buys the promise to do work that nobody has defined yet. That is how a provisional sum in Gabiley can turn into misleading budget certainty: the tender page looks complete, the total looks firm, and the skill the work will actually need sits outside the priced scope.
Why does a provisional sum look certain when the skill is not priced?
A provisional sum is an allowance for work that cannot be measured at tender stage, so the bidder carries the number without carrying the method. General practice is that the sum gets adjusted when the work is instructed, and that instruction is where the real price appears. Read your own contract for what it allows before you treat any line as fixed.
When the priced scope stops at the allowance, the contractor has no reason to study the ground, the access or the finish the job will demand. The bidder who wins on the lowest total can be the one who never planned how the work gets done. Nothing on the tender page shows whether the crew, the plant or the testing exists.
Before you compare bids, ask each bidder to write down, in one page, how they would carry out the likely work behind the sum and who would supervise it. That page costs nothing to read and tells you more than the total.
Where does the unpriced skill gap actually show up on site?
The gap appears when the work is instructed and the contractor sends whoever is available, because no one priced the specific trade or the supervision it needs. Ask the project engineer which site records exist for the area before you plan the programme, and check what your contract allows when instructed work depends on weather.
If the instruction does not name a method, a test and a supervisor, the crew decides those on the day. The client then pays twice: once for the original work, and again to correct workmanship that was never checked against a stated standard. This is what makes the budget certainty misleading. The tender total did not fall, but the money that should have bought competent labour stayed unspent.
Ask the municipal engineer's office what records, if any, it holds for similar work in the area. Walk a recent site with the same kind of instruction and look at the finished work, not the brochure. A short walk tells you more about skill than a bid document can.
How do you close the gap when you instruct the work?
Close it in the instruction: name the method, the test, the supervisor and the acceptance criteria before the work starts. General practice is to agree in advance what proves the work is correct, whether that is a witnessed test, a sample panel or a recorded level check. Confirm the exact limits against the project's specification or engineer, because those limits belong to the design, not to a habit.
Write the instruction so a person, not a company, is named as responsible for supervision. Then check that person is on site when the work happens. Keep a dated record of who attended, what was tested and what failed.
If the contract allows, ask for a priced breakdown of the instructed work before it begins. If the contractor cannot show a rate for labour, plant and testing, the skill was never priced. Check what your contract allows before you hold or release anything.
What to do next
Open your tender file and find every provisional sum. For each one, write the likely work, the trade it needs and the test that would prove it. Send that list to the client's representative or quantity surveyor and ask them to confirm how your contract prices it. Then ask the municipal engineer's office what records, if any, it holds for that work in Gabiley.
Frequently asked questions
Can a client reject a bid because the provisional sum is too low?
That depends on the evaluation rules in the tender document. Ask the client's procurement lead what the rules allow before you raise it, and put your concern in writing with the method question attached.
Should a contractor include supervision in a provisional sum?
General practice is to price labour, plant, testing and supervision separately rather than bury them in one figure. Check what your contract requires for instructed work.
Local reporting: this article is written for building work in Gabiley and Somaliland. Ground conditions, prices and rules differ between places; confirm the details for your own site.