Cube vs. Mosaic for a General Contractor's WIP and Job Costing

Over billing, under billing, retainage, and change orders all flow through a work-in-progress schedule that recalculates earned revenue every time a project manager revises a cost-to-complete estimate. That schedule is the thing your financial model needs to consolidate across every open job, not a generic revenue line.

A model that treats each job as a flat monthly revenue number instead of pulling from the WIP schedule will drift from your actual percentage-of-completion revenue within a quarter or two, especially on jobs with heavy change order activity. The drift compounds because a job running behind on cost-to-complete updates in one month tends to keep running behind, since the same project manager who's too busy to update the estimate this month is usually too busy next month too.

Most contractors already maintain a WIP schedule in Excel because job-cost software rarely models it the way a controller wants to see it. Cube's spreadsheet-native approach means that schedule can stay exactly where it is, with data pulled from your job-cost accounting system instead of retyped from a report each month.

This is the more natural starting point if your controller is confident in the WIP logic already and just wants the tedious data gathering automated, rather than handed to a brand new interface. It also keeps the formulas auditable for a bonding company or a bank that wants to see exactly how over billing and under billing are calculated, line by line.

Once you're running a dozen or more jobs and reporting to an owner, a bank, or a bonding company, a dashboard that rolls every job's backlog, billed to date, and remaining cost to complete into one view can save real time compared with rebuilding that roll-up in a spreadsheet every month.

The fit depends on whether Mosaic can actually mirror your WIP calculation logic rather than approximate it; confirm in a demo that over billing and under billing come through correctly before committing, since construction accounting is easy to get subtly wrong in a general-purpose tool built for other industries first.

Backlog, the value of signed but not yet completed work, is your leading indicator of next quarter's revenue, more useful than trailing revenue trends. Build a rolling view of backlog by expected completion month, updated whenever a job is won, lost, or its schedule slips, and treat any job more than a quarter out as a range rather than a firm number, since weather, permitting, and subcontractor availability all move completion dates.

A common mistake is forecasting next year's revenue off this year's backlog without adjusting for jobs likely to slip into the following period; a contractor with heavy exterior or civil work should expect a meaningful share of late-year backlog to push into the next fiscal year, and the forecast should say so explicitly rather than assuming every job finishes on its original schedule.

Jirav's strength is building a three-statement forecast off operational drivers rather than a flat trend line, which suits a contractor whose headcount, especially field supervision and project management staff, scales with the number of concurrent jobs rather than with revenue alone. If you're planning to grow from a handful of concurrent jobs to twice that, a driver-based model tells you how many more project managers and superintendents that growth actually requires, rather than assuming the existing team can simply absorb it.

A surety underwriter cares less about which software you use and more about whether your WIP schedule is internally consistent and produced on a predictable monthly cadence. Before you switch tools, ask your bonding agent what format and level of detail they expect to see, and confirm whichever platform you choose can produce that same output without a manual rebuild each time a renewal or a new bond request comes up.

Ask these questions before you change tools:

• Ask your bonding agent what format and level of detail they expect in the WIP schedule before you switch platforms.
• Confirm the platform can produce that same WIP output every month without a manual rebuild.
• Check that the tool mirrors your own WIP logic, including over billing, under billing, retainage, and change orders, instead of substituting a generic revenue line.
• Verify the schedule is internally consistent and produced on a predictable monthly cadence, since that matters more to a surety underwriter than the software brand.
• Treat any job more than a quarter out as a range in the backlog view, not a firm number.