In brief
- A claim of tank waterproofing experience in Borama is not evidence, so a client or procurement team should ask for written method statements, product data sheets and test records for tanks the same crew built.
- A waterproofing system fails at the joints, the base slab, the pipe penetrations and the roof slab, and each of these points can be inspected before the tank is filled.
- Arrange a supervised fill test with the level recorded for a stated period, and check what your contract says about defects and retention before you sign.
Contents
Tank waterproofing competency risks in Borama show up when a crew is judged on what it says about its experience rather than on records of tanks it has built and tested. Two things reduce that risk. First, evidence in writing. Second, a fill test the client or an engineer witnesses, with the water level written down at the start and the end.
A written claim costs nothing, and a verbal claim costs less. Ask for the documents that a waterproofing crew keeping proper records can supply: the manufacturer's data sheet for the membrane or coating, the method statement for the base slab, the wall-to-floor junction and the pipe penetrations, and the batch or delivery note showing the product matches the specification. If the crew cannot produce the data sheet for the product it proposes, the specification cannot be checked against it.
How does unverified tank waterproofing competency put a Borama tank at risk?
Because the person checking the work may not know what the crew can do, the weak points get covered before anyone sees them. A tank leaks at the details, not in the middle of a large flat panel: the construction joint where wall meets base, the pipe and cable entries, the corners, and the roof slab or cover. Waterproofing is a sequence. The substrate must be sound and dry enough for the product, the surface prepared, the product installed at the thickness and number of coats the data sheet states, and curing respected between coats. If a crew has only tiled or painted, it may treat the membrane as paint and skip substrate preparation. The leak then appears after the tank is enclosed and the site work is finished, when repair means breaking out finishes. Competency should be judged on records and site evidence rather than on where a crew says it has worked. Ask the municipal engineer's office directly what records or drawings it holds for water tanks, and ask a laboratory for its rate if stored water quality is also a concern.
What should you ask to see before awarding the work?
Ask for records of a completed tank, then go and look at that tank. A method statement, a product data sheet, a material delivery note, a daily site record and a fill test result for one tank mean more than a verbal list of projects. Bring a tape measure and a spirit level to the site visit and check what you can see: the number of coats against the data sheet, the thickness or dry film thickness if a gauge is available, the treatment of the wall-to-base junction, and how the pipe entries are sealed. Talk to the person who will actually install the membrane, not only the person who signed the bid. If the crew cannot name the product it used on its reference tank, the record is not usable.
How do you run the fill test that decides the matter?
Agree the test before the tank is filled, and put it in the contract. A fill test is the only check that exercises the whole system at once, following general practice with the duration and the acceptable loss confirmed against the project specification or the engineer. Record the water level on a fixed mark or a staff, note the time, cover the tank if it is open, and read the level again after the agreed period. Watch the outside faces for damp patches, staining and weeping at joints and penetrations during and after filling. Keep photographs of the level marks and of any damp patch with the date. If the tank is below ground, the surrounding backfill and groundwater can hide a leak, so check the internal faces of the walls and base as well. Do not fill against a painted surface that the product data sheet says must be left dry, and confirm the waiting period the manufacturer states before filling.
What to do next
Before you sign, ask the bidders for a written method statement, the product data sheet and one reference tank you can visit. Then agree the fill test duration and the level mark in writing, and check what your contract says about defects, retesting and retention. If the bidders cannot supply the documents, keep looking.
Frequently asked questions
Does a waterproofing warranty replace a fill test?
No. A warranty is a promise about the future, and its terms matter. Read what it covers, how long it runs, and who pays for access if the tank is enclosed. Check what the contract says about defects and retention, because a warranty does not show that the tank holds water today.
Can a tank be tested before the pipework is connected?
A tank can be filled and checked for leakage on its own, before the pipework is connected, and this is often the cleaner test because it isolates the shell. Confirm the sequence with your engineer, then test the pipe connections and penetrations separately once they are installed.
How much water loss is acceptable in a fill test?
There is no single figure to quote. Allowance depends on the tank size, the surface area, exposure and the specification. Ask your engineer or the project specification for the acceptable loss over the test period, and record the level and the period so the result can be checked.
Local reporting: this article is written for building work in Borama and Somaliland. Ground conditions, prices and rules differ between places; confirm the details for your own site.