By the MassBid Estimation team · Reviewed by a senior estimator with 10+ years of experience · Published · Updated
In short
UniFormat classifies a building by its physical systems, or elements, such as A Substructure, B Shell, C Interiors and D Services, so a cost can be estimated before materials are chosen. MasterFormat classifies the work results and products that build those systems, in 50 numbered divisions such as 03 Concrete and 09 Finishes. Estimators use UniFormat for early, elemental budgets and MasterFormat for specifications, detailed estimates and bids.
- UniFormat organizes by
- Building system or element (what it is)
- MasterFormat organizes by
- Work result, trade and product (what it is made of)
- UniFormat codes
- Letter and numbers: B2010 Exterior Walls
- MasterFormat codes
- Six digits: 04 22 00 Concrete Unit Masonry
- UniFormat top level
- A to G, plus Z General
- MasterFormat top level
- Divisions 00 to 49
- Best stage for UniFormat
- Concept and schematic design
- Best stage for MasterFormat
- Construction documents and bidding
The difference, in one table
Take an exterior wall. In UniFormat it is one element, B2010 Exterior Walls, with one cost per square foot of wall. In MasterFormat the same wall is split into the work that builds it: block in Division 04, studs and sheathing in 05 or 06, insulation, air barrier and sealants in 07, and paint in 09. Both describe the same wall; they answer different questions.
| UniFormat | MasterFormat | |
|---|---|---|
| Organizes by | Building systems and elements | Work results, trades and products |
| Answers | What does each part of the building cost? | What does each trade's work cost? |
| Code format | Letter plus numbers, such as D3040 | Six digits, such as 23 31 13 |
| Top level | A Substructure to G Sitework, plus Z General | 50 divisions, 00 to 49 |
| Needs materials chosen? | No: a wall is a wall before its materials are | Yes: work is sorted by what it is made of |
| Typical stage | Concept, schematic and early design development | Construction documents, bidding and construction |
| Typical uses | Budgets, design-to-cost targets, comparing options, life-cycle cost, facility management | Specifications, bid packages, detailed estimates, subcontracts, cost tracking |
| Published by | CSI and CSC; ASTM as E1557 UniFormat II | CSI and CSC |
MasterFormat's divisions, with what each covers and a lookup by trade, are in our full list of CSI MasterFormat divisions.
UniFormat codes: the Level 1 and Level 2 list
UniFormat II, as published by ASTM International in standard E1557, has four levels. Level 1 is the major group, Level 2 the group element, Level 3 the individual element and Level 4 the sub-element. Levels 1 to 3 are the ones used for estimating:
| Level 1 | Level 2 | Group element |
|---|---|---|
| A Substructure | A10 | Foundations |
| A Substructure | A20 | Basement Construction |
| B Shell | B10 | Superstructure |
| B Shell | B20 | Exterior Enclosure |
| B Shell | B30 | Roofing |
| C Interiors | C10 | Interior Construction |
| C Interiors | C20 | Stairs |
| C Interiors | C30 | Interior Finishes |
| D Services | D10 | Conveying |
| D Services | D20 | Plumbing |
| D Services | D30 | HVAC |
| D Services | D40 | Fire Protection |
| D Services | D50 | Electrical |
| E Equipment and Furnishings | E10 | Equipment |
| E Equipment and Furnishings | E20 | Furnishings |
| F Special Construction and Demolition | F10 | Special Construction |
| F Special Construction and Demolition | F20 | Selective Building Demolition |
| G Building Sitework | G10 | Site Preparation |
| G Building Sitework | G20 | Site Improvements |
| G Building Sitework | G30 | Site Mechanical Utilities |
| G Building Sitework | G40 | Site Electrical Utilities |
| G Building Sitework | G90 | Other Site Construction |
Level 3: where an elemental estimate is priced
An elemental estimate prices each Level 3 element in its own unit, usually the unit that grows with the design rather than with the materials. That is what lets a cost be tested before anything is specified.
| Code | Element | Usually priced per |
|---|---|---|
| A1010 | Standard Foundations | Linear foot of footing or square foot of footprint |
| A1030 | Slab on Grade | Square foot of slab |
| B1010 | Floor Construction | Square foot of supported floor |
| B2010 | Exterior Walls | Square foot of wall, net of openings |
| B2020 | Exterior Windows | Square foot of glazing, or each |
| B3010 | Roof Coverings | Square foot of roof |
| C1010 | Partitions | Square foot of partition |
| C3020 | Floor Finishes | Square foot of floor |
| D2010 | Plumbing Fixtures | Each fixture |
| D3040 | HVAC Distribution Systems | Square foot of building, or ton of cooling |
| D4010 | Sprinklers | Square foot of building |
| D5020 | Lighting and Branch Wiring | Square foot of building |
The quantities behind these units are a takeoff in their own right, only coarser: wall area instead of block count, fixture count instead of pipe by diameter. The difference between the two kinds of work is in quantity takeoff vs cost estimate.
UniFormat to MasterFormat crosswalk
There is no one-to-one conversion. One element draws on several divisions, and one division feeds several elements. This is the crosswalk we use when an estimate has to be reported both ways:
| UniFormat element | Usual MasterFormat divisions |
|---|---|
| A10 Foundations | 03 Concrete, 31 Earthwork |
| A20 Basement Construction | 03 Concrete, 07 Thermal and Moisture Protection, 31 Earthwork |
| B10 Superstructure | 03 Concrete, 05 Metals, 06 Wood, Plastics and Composites |
| B20 Exterior Enclosure | 04 Masonry, 05 Metals, 06 Wood, 07 Thermal and Moisture, 08 Openings, 09 Finishes |
| B30 Roofing | 07 Thermal and Moisture Protection, 08 Openings (skylights) |
| C10 Interior Construction | 06 Wood, 08 Openings, 09 Finishes, 10 Specialties |
| C20 Stairs | 03 Concrete, 05 Metals, 06 Wood, 09 Finishes |
| C30 Interior Finishes | 09 Finishes |
| D10 Conveying | 14 Conveying Equipment |
| D20 Plumbing | 22 Plumbing |
| D30 HVAC | 23 HVAC, 25 Integrated Automation |
| D40 Fire Protection | 21 Fire Suppression |
| D50 Electrical | 26 Electrical, 27 Communications, 28 Electronic Safety and Security |
| E10 Equipment, E20 Furnishings | 11 Equipment, 12 Furnishings |
| F10 Special Construction | 13 Special Construction |
| F20 Selective Building Demolition | 02 Existing Conditions |
| G10 to G90 Sitework | 02 Existing Conditions, 31 Earthwork, 32 Exterior Improvements, 33 Utilities |
| Z General (UniFormat 2010) | 01 General Requirements |
The practical way to keep both is to tag each estimate line with a code from each system. The line is priced once, and the summary can be sorted by element for the owner or by division for the bid.
Which one to use at each stage of design
The choice follows how much of the design exists. AACE International's cost estimate classification ranks estimates from Class 5, on almost no design, to Class 1, on complete documents, with the expected accuracy range narrowing as the design matures:
| Class | Typical stage | Widest expected range | Usually organized by |
|---|---|---|---|
| Class 5 | Concept, program only | −50% to +100% | Cost per square foot, UniFormat Level 1 |
| Class 4 | Schematic design | −30% to +50% | UniFormat Level 2 and 3 |
| Class 3 | Design development | −20% to +30% | UniFormat Level 3, moving to MasterFormat |
| Class 2 | Construction documents | −15% to +20% | MasterFormat, from a full takeoff |
| Class 1 | Bid documents | −10% to +15% | MasterFormat, from a full takeoff |
A square-foot number is where most budgets start; our construction cost per square foot by city shows the published ranges. Once drawings are complete, the bid is built division by division, as in how to read a construction estimate.
A real estimate, sorted both ways
This is the trade cost of an 8,020 square foot salon and spa interior renovation in Illinois that we estimated by MasterFormat division, regrouped by UniFormat Level 1. The total does not change. What changes is the story it tells.
| UniFormat group | MasterFormat divisions in it | Cost | Per sq ft | Share |
|---|---|---|---|---|
| C Interiors | 06, 08, 09, 10 | $378,986 | $47.26 | 46% |
| D Services | 22, 23, 26, 27 | $339,407 | $42.32 | 41% |
| Z General | 01 | $62,500 | $7.79 | 8% |
| F Demolition | 02 | $29,280 | $3.65 | 4% |
| E Equipment and Furnishings | 11, 12 | $9,258 | $1.15 | 1% |
| Total trade cost | $819,430 | $102.17 | 100% |
Sorted by division, the biggest number is Division 09 Finishes at $289,800. Sorted by element, 87 percent of the job is two things, the interior fit-out at 46 percent and the building services at 41, and there is nothing at all in A Substructure, B Shell or G Sitework. That second view is the one an owner uses to compare this renovation with the next, and the first is the one a contractor uses to buy it out.
Where OmniClass fits
OmniClass is the wider classification system used mainly in building information modeling. Its Table 21, Elements, is based on UniFormat, and its Table 22, Work Results, is based on MasterFormat, with OmniClass's own numbering. A model element tagged with a Table 21 code can therefore be costed by element, and the same element's materials can be traced to MasterFormat sections. In practice, estimates and specifications in the US are still organized by UniFormat and MasterFormat directly.
Common mistakes with the two systems
- Comparing a UniFormat budget with a MasterFormat bid line by line, when the lines do not mean the same thing.
- Converting division totals to elements without moving individual lines, so exterior storefronts land in Interiors.
- Carrying an early elemental budget into a bid without a full takeoff once the drawings are complete.
- Leaving general requirements, overhead and contingency out of an elemental budget because no element owns them.
- Using the UniFormat II and UniFormat 2010 codes interchangeably; some Level 2 codes differ between the two.
How we organize the estimates we deliver
Our estimates are organized by CSI MasterFormat division, with a summary page by division, so they line up with the specifications and the bid packages. If an owner, designer or lender needs the summary grouped by UniFormat element, say so when you send the drawings and we will confirm it in the quote. See GC estimating and the sample estimates, or send the drawings for a free quote.
Common questions
UniFormat organizes a building by systems and elements, such as foundations, exterior walls and HVAC. MasterFormat organizes it by work results and products, in 50 divisions such as 03 Concrete and 23 HVAC. UniFormat suits early budgets; MasterFormat suits specifications and bids.
A classification of building elements and related sitework, grouped A Substructure, B Shell, C Interiors, D Services, E Equipment and Furnishings, F Special Construction and Demolition and G Building Sitework, with Z General in the CSI edition. It is used for elemental cost estimates, design-to-cost targets and facility management.
The version of UniFormat standardized by ASTM International as E1557, Standard Classification for Building Elements and Related Sitework. NIST published a guide to it in 1999.
The Construction Specifications Institute (CSI) and Construction Specifications Canada (CSC) publish UniFormat, most recently in 2010. ASTM International publishes UniFormat II as standard E1557. CSI and CSC also publish MasterFormat.
Level 1 is the major group, such as B Shell; Level 2 the group element, such as B20 Exterior Enclosure; Level 3 the individual element, such as B2010 Exterior Walls; and Level 4 the sub-element. Estimates are usually priced at Level 3.
Exterior Walls, within B20 Exterior Enclosure in B Shell. It is usually priced per square foot of wall, net of windows and doors, which are B2020 and B2030.
HVAC, within D Services. Its Level 3 elements cover energy supply, heat and cooling generation, distribution, terminal and package units, controls, and testing and balancing. In MasterFormat the same work is mainly Division 23.
It depends on the stage. UniFormat is better before materials are chosen, for budgets and comparing design options. MasterFormat is better once construction documents exist, for a detailed estimate built from a full takeoff and for bidding.
Yes, line by line. Each estimate line is assigned to the element it builds; converting whole division totals gives misleading results, because one division feeds several elements.
An estimate priced by building element, such as foundations, exterior walls or plumbing fixtures, each in its own unit. It is organized by UniFormat and used mainly before the design is detailed enough for a full takeoff.
OmniClass Table 21, Elements, is based on UniFormat, and Table 22, Work Results, is based on MasterFormat. OmniClass is used mainly to classify information in building information models.
Sources
- ASTM E1557: Standard Classification for Building Elements and Related Sitework, UNIFORMAT II
- NIST, Charette and Marshall (1999), UNIFORMAT II Elemental Classification for Building Specifications, Cost Estimating and Cost Analysis
- Construction Specifications Institute, UniFormat
- Construction Specifications Institute, MasterFormat
- Construction Specifications Institute, OmniClass
- AACE International, Recommended Practices (cost estimate classification)