Quoting and BOQ Software for Interior Fit-Out Contractors

Interior fit-out is priced twice: once quickly to win the job, and again slowly when the site measurements come back and the drawings are firmed up. The gap between those two numbers is where most of the margin goes.

The work itself is parametric — panel areas, running lengths, hardware counts, finishes — but the tool is almost always a spreadsheet inherited from a previous project. It carries old rates, hidden formulas and whichever assumptions the last estimator made and never wrote down.

What a bill of quantities actually has to carry

A BOQ is a priced list of the work, item by item, each with a description, a unit, a quantity and a rate. It looks like a document and behaves like a calculation, and the difference matters because every one of those quantities is derived from a measurement and every rate is derived from a build-up.

A joinery line is not one number. Behind a run of base units sits the carcass board area, the shutter area, the edge banding by running metre, the hinges and drawer channels by count, the handles, the back panel, the skirting or plinth, the finish on each visible face and the labour to assemble and install it. Behind a partition line sits GI stud spacing, board layers and thickness, insulation, tape and jointing, and the paint or laminate finish on top.

Two things follow. The unit has to be stated and honoured — a shutter priced per square foot and measured per running foot is a mistake that survives all the way to a bill. And the mode of measurement has to be agreed, because whether a deduction is taken for an opening, and at what size, changes the quantity on a line neither side thinks is contentious.

Where the measurements come from, and when

Early enquiries are priced from a drawing, sometimes a concept one. Firm pricing waits for a site survey, and what the survey brings back decides how close the first number was.

The survey has to return clear dimensions at working height rather than at floor level, the out-of-square of each wall, slab-to-slab height and whatever service the ceiling has to dodge, floor level variation across the area, and the access route — door widths, lift car dimensions, stair turns — which decides what is built in the workshop and what is assembled on site. It also has to record what is genuinely there against what the drawing claims, because a column that moved 90 mm changes a run of units and nothing else in the drawing will tell you.

The parametric nature of the work is what makes this tractable. Once dimensions are captured as numbers rather than as a marked-up print, the quantities can be recomputed rather than re-measured, and a firm price is a re-run rather than a rebuild.

Why the spreadsheet eventually lies

It does not fail loudly. It drifts.

Rates are updated in one copy and not another. A wastage allowance is adjusted for a difficult job and left adjusted. Formulas that were referenced but never written return a zero that looks like a legitimately free line. Rows are added by people who have since left, and nobody can say which assumptions produced which price. Because the workbook keeps the total and discards the working, the question that gets asked later — why is this line that number — has no answer anywhere in the file.

The shared consequence is that two estimators on the same firm quote the same scope differently, and the difference is invisible until one of them wins a job that cannot be built at the price.

How variations actually happen, and what they cost

A variation is a change to the agreed scope after the contract price is fixed. On a fit-out they are not exceptional; they are the normal condition of the job. The client adds a wall shelf, the finish changes from laminate to veneer on the visible faces, a partition moves 300 mm because a services route would not clear.

The failure is almost never the change itself. It is that the change is agreed on site, verbally, and priced weeks later — by which point the work is done and the negotiation has no leverage. The sequence that protects margin is the boring one: the variation is raised as a revision against the accepted scope, priced from the same rate library, and issued as a document showing the previous total, what was added or removed, and the new total, with a date and a name against the approval.

Keeping the original scope intact matters as much as pricing the change. If the accepted quotation is edited in place, there is no longer a baseline to measure the variation against, and the argument becomes about the whole job rather than about one wall.

How the money is billed

Fit-out is rarely paid in one go. Interim payment runs against measured work — a running account bill for what has actually been completed in the period, valued at BOQ rates, with retention held back against snagging and released after the defects liability period. Variations either sit in their own section of the bill or fold into the measured quantities, and which of those was agreed is worth writing down before the first bill rather than after it.

Two details on the document itself repay attention. Lines want grouping into sections by area — the kitchen, the reception, the meeting rooms — with a stable reference per line, because that is how both the client and the site team will talk about them for the rest of the job. And transport, installation and commissioning are separate charges applied after the discount and before tax, not percentages folded into rates, or the first variation makes the whole build-up untraceable.

That structure only works if the measurement, the rate and the bill all read from the same place. When the BOQ lives in one spreadsheet and the bill is typed from a site measurement sheet, the two diverge in the same predictable way an invoice diverges from a purchase order: not by dispute, but by three people entering the same facts from different memories.

Why generic estimating software does not fit

Catalogue-based quoting tools assume a product list with prices. Fit-out has a rate library and a set of measurements, which is a different shape — a rate is a build-up, and the quantity it is multiplied by is computed from site dimensions rather than chosen from a dropdown.

Full construction ERP sits at the other end: procurement, subcontractor accounting, plant, payroll and a general ledger, sold as a programme rather than a tool. If the bottleneck is that a BOQ takes three days to price and a variation takes a week to quote, that is where the work should start.

The test worth running on any demo is the same one that separates catalogue tools from formula tools anywhere: change a dimension and watch whether the price moves proportionately to material and labour, or in steps. Steps mean somebody has to create every variant by hand, and that maintenance never ends.

When this is not the right fit

If you subcontract essentially everything and your commercial job is to assemble other people’s quotations into a tender, a rate library and a parametric pricing engine solve a problem you do not have. What you need is comparison and coordination, which is a different tool.

If the volume is one project at a time and one person prices it, the spreadsheet is still the right answer. The point where it stops being right is when two estimators are pricing to two sets of rates, or when a variation has to be defended against a client who has the original document and you have three copies of it.

And this is a quoting, BOQ and variation tool rather than a site programme. It does not replace scheduling, a snag list app or a project accounting system, and a firm that needs those should say so and buy them separately rather than expect one product to be all three.