Budget for adding a new bathroom: rough-in, fixtures and permits

In this example the plumbing is split in two. The rough-in has an accepted quote, while the trim and fixture install have none yet, so one plumbing line is committed and the other reads Not committed.

General information only, not financial, construction or legal advice. Contingency, holdback and payment-split percentages are your own inputs, and payment and deposit rules vary by contract and by state or province; check yours. Names and numbers in the example are invented.

What changes for this kind of project

In this example each trade gets its own line. Framing and blocking go in for the pipes, electrical gets its rough-in and exhaust vent, then drywall and tile close it up. Giving the plumbing a rough-in line and a trim line lets the first be committed and part-paid while the second waits for a quote. Apex Framing sits on two lines, framing and drywall, because one crew does both jobs.

Two approved change orders show up in the example. The vent line move adds to the plumbing rough-in, whose quote already sits above its line budget, and the approved vanity outlet pushes the electrical line over its budget. Both overruns draw on the contingency pool. The heated floor mat is only Proposed, so it counts as pending exposure and stays out of Committed until you approve it.

A worked example: New bathroom, 40 sq ft

Invented numbers, to show the shape. Settings on Start Here: contingency 12% (an example value you set), total project budget $16,500.

The contingency pool is $1,980 ($16,500 x 12%). That leaves $14,520 to share out as line budgets. The lines below add up to $14,500, so $20 is unallocated.

Change orders on the Change Orders tab. Only Approved rows move into Committed:

What the summary shows

• Committed: $13,500. Paid: $3,800. Unpaid commitment: $9,700.
• Contingency used: $650, what each line's committed total goes above its line budget, added up. Contingency left now: $1,330.
• Pending exposure (Proposed change orders): $420. Contingency left if every proposed change order were approved: $1,060.

Where each piece goes in the workbook

1. Start Here: Type the total project budget, which includes the contingency pool, and a contingency percentage you can overtype. List Apex Framing, Current Electric, Metro Plumbing and Tile Masters as your contractors.
2. Budget: Give each trade its own line: framing, electrical rough-in, plumbing rough-in, drywall, tile, plumbing trim, fixtures and the permit. Leave the accepted quote empty on the trim line until Metro Plumbing sends one; it reads Not committed.
3. Change Orders: Log the vent line move and the vanity outlet as Approved so they raise Committed on L03 and L02. Log the heated floor mat as Proposed against L05 and it shows only as pending exposure.
4. Payments: Log each payment against its Line ID with an invoice reference. Paid and Unpaid commitment on the Budget tab come from those rows, and the tie-out check shows a difference if a payment has a blank or misspelled Line ID.

Two formulas worth a cell of their own

• Committed for one room: =SUMIFS(Budget!$K$6:$K$65,Budget!$B$6:$B$65,"Bathroom") returns $13,500 on this example.
• Contingency used, the sum of the Overrun now column: =SUM(Budget!$S$6:$S$65) returns $650.

Four tracking tips

1. A line with no accepted quote is not zero spend: its Forecast uses the line budget until you type a quote. Read Forecast on the plumbing trim line to see what the open work is assumed to cost.
2. The vent move on the rough-in is an approved change order, but percent milestones on the Cash Schedule use the original quote. Add that change as its own Fixed $ row for Metro Plumbing so the schedule covers it.
3. A line with no contractor, like the owner-bought toilet, sink and faucet, is not part of any trade's contract on the Contractors tab. It still counts in the Budget totals and in the room and category totals.
4. Before you approve the heated floor mat, compare Contingency left now with Contingency left if all pending approved. The second figure shows the pool after that mat and any other open proposal are accepted.

Questions

Can I leave the plumbing trim without a quote while the rough-in is under way?

Yes. Leave Accepted quote empty on the trim line and it reads Not committed, with Committed at zero. Type the quote in when Metro Plumbing sends it. The rough-in line is separate, so it can carry payments and change orders in the meantime.

The plumbing rough-in line reads Over budget. Where does the extra come from?

Committed is the quote plus approved change orders. Here the rough-in quote already sits above its line budget and the approved vent move adds more, so Remaining goes negative. The amount above the line budget counts in Contingency used, which draws on the pool. A tile quote under budget does not refill it.

Related renovation guides

• Bathroom remodel budget spreadsheet in Excel: how much is really left
• Renovation budget by room spreadsheet: SUMIFS per room, with an overrun flag
• Renovation change order tracker: a spreadsheet for homeowners

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