Schedule of Values in Construction: How to Read, Compare, and Spot Padded Bids

You receive three bids for a mechanical scope. The lump sums are $340,000, $410,000, and $520,000. The bottom line tells you nothing about why those numbers differ. Is the low bidder missing half the scope? Is the high bidder padding? Without a line-by-line breakdown, you are comparing envelopes, not proposals.

That breakdown has a name: the schedule of values (SOV). It decomposes a contractor's lump-sum price into individual line items, each with a description, unit, quantity, unit price, and extended total. This guide explains what an SOV is, how to read each line, and how to compare multiple SOVs to pick the best bid.

What is a schedule of values?

A schedule of values is a table in which the contractor breaks down the total contract price into line items tied to specific work activities. Each line shows what is being done, how much of it, at what rate, and the total cost for that item. The sum of all lines equals the contract amount.

The SOV serves three purposes beyond the initial bid:

• Bid comparison. It is the only way to compare lump-sum bids on anything other than total price. You see where each contractor puts the money.
• Progress billing. During construction, the SOV becomes the basis for monthly pay applications. Each line item is billed as a percentage of completion. A well-structured SOV makes payment processing straightforward. A poorly structured one creates monthly disputes.
• Change order pricing. When scope changes, the original unit prices serve as the reference for pricing additions or deductions.

Anatomy of an SOV

An SOV is organised hierarchically. In the US, line items typically follow CSI MasterFormat divisions (Division 03 for concrete, Division 09 for finishes, Division 23 for HVAC). In the UK, RICS New Rules of Measurement (NRM) provide an equivalent framework. The numbering matters less than the principle: every line item maps to a recognisable scope of work.

The typical hierarchy:

Division (or trade) → the broad scope area (e.g., Division 22 - Plumbing).

Section → a functional subdivision (e.g., 22.10 - Domestic water piping, 22.20 - Drainage, 22.30 - Fixtures).

Line item → a specific deliverable (e.g., 22.10.01 - 3/4" copper supply line, 22.10.02 - 1" copper supply line).

Here is a simplified excerpt for a plumbing scope on a commercial renovation:

How to read each line

Every column carries weight.

Description. It must be specific enough for another professional to understand the work without ambiguity. "Partition" tells you nothing. "3-5/8" metal stud partition, 5/8" Type X GWB each side, R-11 batt insulation, 9'-0" height" tells you exactly what is priced. Vague descriptions make unit prices uncheckable.

Unit. Common units include LF (linear foot), SF (square foot), CY (cubic yard), EA (each), LS (lump sum). Watch out for "LS" and "LOT." These are black boxes. A line item priced as a lump sum gives you no usable unit rate for change orders. The more lump-sum lines an SOV contains, the less transparency you have.

Quantity. Quantities should come from the project drawings and specifications. On a well-run bid, the owner or architect provides a quantity survey so all bidders price the same volumes. If a contractor modifies the quantities, that is either a takeoff disagreement or an error. Either way, it needs clarification before award.

Unit price. This is the core of the analysis. The unit price should cover material, labour, equipment, overhead, and profit for that specific item. A unit price that is abnormally low on one line often means the contractor has front-loaded another line, a practice that distorts progress payments and change order pricing.

Extended total. Quantity times unit price. Always verify the arithmetic. Spreadsheet errors are surprisingly common when the SOV is filled in manually.

5-step method to compare multiple SOVs

1. Confirm identical scope

Before comparing prices, verify that every bidder priced the same scope. Compare the list of line items: same divisions, same items, same quantities. If the owner provided a blank SOV template (strongly recommended), the line items and quantities should be identical across all bids. If each contractor submitted their own format, aligning them will take more work.

2. Flag missing or added line items

A line item present in Bid A but absent in Bid B could mean B forgot it, included it in another line, or considers it outside the scope. Do not assume. Request a written clarification. A line item added by only one bidder may signal a gap in the bid documents that the others missed.

3. Normalise units

If one contractor prices a line item per square foot and another prices it as a lump sum, you cannot compare unit rates. Ask the lump-sum bidder to break it into quantity times unit price. Normalisation is essential for a meaningful line-by-line comparison.

4. Identify abnormally low pricing

A unit price significantly below the other bids on a high-quantity line item is a red flag. The contractor may have made a mistake. Or they may have deliberately underpriced that line to win the bid, knowing they will recover the margin through change orders on related work. Compare each unit price to the average of all bids. An item more than 30% below the mean on a line representing more than 10% of the total warrants a written explanation.

5. Compare totals by division, not just the grand total

Do not stop at the bottom line. Compare division by division, then section by section. Two bids with the same grand total can have very different internal distributions. Contractor A puts 60% of the cost in materials and 40% in labour. Contractor B does the reverse. If a change order involves additional labour, the contractor with the higher labour rate will cost you more. The existing construction bid comparison guide covers the broader evaluation framework, including schedule, logistics, and award decisions.

Common traps

Missing scope items. The contractor omits a spec section. Their total drops. If you award without catching the gap, that missing scope comes back as a change order, typically at a premium over what it would have cost in the base bid.

Modified quantities. The contractor reduces quantities below the owner's takeoff. The total looks lower on paper. If actual field quantities match the original takeoff, you will pay the difference during construction, plus the administrative overhead of processing the overage.

Lump-sum hiding. An SOV where half the lines are priced "LS" defeats its own purpose. You cannot compare unit rates, calculate accurate progress payments, or price change orders against a clear baseline. Require unit pricing on all significant line items. Reserve lump sum for genuinely indivisible items like mobilisation or bonds.

Undisclosed subcontractors. If the general contractor is subbing out a division, the SOV should still detail the line items. A single line reading "Electrical subcontract: $185,000 LS" gives you no visibility. Require the same breakdown from subcontracted divisions as from self-performed ones.

Related documents

Bid form. The standardised form each bidder completes. It captures the total bid amount, alternates, and unit prices. The SOV provides the detail behind the bid form's total.

Bill of quantities (BOQ). The UK and international equivalent of the SOV. A quantity surveyor prepares the BOQ and contractors fill in unit rates. Same principle, different procedure: in US practice the contractor prepares the SOV, in UK practice the QS prepares the BOQ.

GMP contract (Guaranteed Maximum Price). The SOV defines the cost baseline against which savings or overruns are measured. A padded SOV in a GMP contract means the contractor captures savings that should flow back to the owner.

Retainage (US) / Retention (UK). A percentage of each progress payment withheld until completion. Front-loaded SOVs (early-stage items overpriced) let contractors collect more cash upfront and reduce effective retention. Mobilisation priced at 8% of the contract when 2-3% is typical is a classic sign.

FAQ

Is a schedule of values required on every project?

Not by law, but by practice. Most standard contract forms (AIA, ConsensusDocs, JCT, NEC) require an SOV before the first pay application. On a single-trade job under $50,000, a lump-sum bid without one may be fine. On anything with multiple trades or progress payments, it is essential.

Who prepares the schedule of values?

On lump-sum bids, the contractor prepares it. On a well-managed project, the owner provides a blank SOV template so all bidders use the same structure. On design-build or GMP projects, the contractor prepares it and the owner's team reviews for reasonableness.

Can the SOV be changed after the contract is signed?

The SOV is a contract exhibit. Line items and unit prices are fixed unless both parties agree. Scope changes are handled through change orders, which may add lines or adjust quantities, but original unit prices remain the baseline.

How do I spot a front-loaded SOV?

The contractor inflates early-stage items (mobilisation, sitework, foundations) and deflates later ones (finishes, commissioning). Compare each line item's share of the total to industry norms. Site prep at 12% when 5% is typical is front-loading. It reduces your effective retainage and increases exposure if the contractor defaults mid-project.

What is the difference between an SOV and a cost estimate?

The cost estimate is the contractor's internal calculation of what the work costs them. The SOV is what they show you, including markup. The SOV total equals the bid price. The estimate total equals expected cost. The gap is their margin.

Related reading:

• Construction Bid Comparison: How to Evaluate Subcontractor Quotes
• How to Compare Supplier Quotes: The Complete Guide
• Free Vendor Quote Comparison Template

You receive contractor bids in PDF, Excel, or printed sheets and spend hours aligning them manually. Quotal reads your bid documents, structures the line items, and builds a side-by-side comparison in minutes.