A bill of quantities is the most important document in a construction contract, and it is the one clients read least carefully. It is usually handed over as a thick spreadsheet, at the end of a long meeting, when everyone is tired and the price at the bottom is the only figure anyone looks at.
That bottom figure is not the promise. The pages above it are the promise. In 25 years I have seen very few disputes that were not already visible in the BOQ, to anyone who knew where to look. Here is where to look.
1. Can every line be measured on site?
A proper BOQ line names a unit — cubic feet of concrete, square feet of plaster, running feet of skirting, numbers of doors — and a quantity against it. If a line cannot be walked up to and measured with a tape when the work is done, nobody can prove it was delivered.
Lines like “electrical works — lump sum” or “finishing as per design” are not quantities. They are permissions.
2. Are materials named by brand and specification?
“Tiles” is not a specification. “Sanitary fittings” is not a specification. The BOQ should name the brand, the grade or series, the size and the finish — and ideally say what happens if that item is unavailable when the time comes.
This is where most quality complaints are born. The client pictured one thing, the rate was priced for another, and both parties were technically correct.
3. What is hiding in the provisional sums?
A provisional sum is money set aside for work that has not been designed yet. There is nothing wrong with that — sometimes a decision genuinely cannot be made at tender stage. The danger is how much of the contract sits inside them.
Add the provisional sums up and express them as a percentage of the total. If a meaningful part of your project is provisional, then a meaningful part of your price is not yet a price. Ask when each one will be fixed, and by whom.
4. Check the quantities, not only the rates
Clients negotiate hard on rates and almost never check quantities. Both matter equally: the cost of a line is the rate multiplied by the quantity, and an over-measured quantity at a keen rate still costs you more than a fair quantity at a fair rate.
You do not need to re-measure the whole building. Take three or four of the largest lines by value — usually concrete, masonry, plaster and flooring — and check those against the drawings. If the big lines are honest, the small ones usually are too.
5. Read what the rate is said to include
Every BOQ has preamble notes, and almost nobody reads them. They decide whether a rate includes materials, labour, scaffolding, wastage, curing, hoisting to upper floors, cutting and making good, and clearing away. Two identical-looking rates from two contractors can mean very different things once you read what each one covers.
6. What is not in the BOQ is what will cost you
Look deliberately for what is missing. Excavation and disposal of spoil. Dewatering. Temporary electricity and water. Site security. Approvals and utility connection charges. External development — boundary wall, gate, driveway, landscaping. Municipal fees.
None of these are dishonest to leave out, provided everyone knows they are out. They become a problem when the client believed the bottom figure was the cost of the finished house.
7. Does the payment schedule follow the BOQ?
The BOQ and the payment plan should describe the same project. Payments should be released against measured, completed and inspected work — not against the calendar, and not in round figures that bear no relation to what has actually been built.
If the payment schedule cannot be reconciled with the bill of quantities, one of the two documents is decorative.
The honest summary
A good BOQ protects the contractor as much as the client. It settles arguments before they happen, and it means the person doing the work is paid for what they actually did. When we issue one, we would rather a client questioned every line than signed it unread — because an unread BOQ produces a dispute six months later, and disputes are more expensive than explanations.
If you have a BOQ in front of you now and you are not sure what you are reading, bring it to us. We will go through it with you, whether or not you build with us.