US Construction Estimating Constants

A table of the constants that the TakeoffMetric calculators use to turn dimensions into order quantities: bag yields, aggregate and soil densities, swell and compaction ratios, rebar weights, dressed lumber sizes, block counts, mortar rules of thumb, paver base depths, shingle coverage, asphalt unit weights and air properties for duct sizing. Each row gives one value, its unit, an SI conversion, the condition it applies to, and a link to the primary source it was read from.

Compiled 2026-09-29 by TakeoffMetric Editorial (TakeOffMetrics Research). 148 rows.

Files

Columns

id · category · material_or_item · quantity · value · unit · value_si · unit_si · condition · source_publisher · source_title · source_url · source_type · date_opened · used_by_tool_url · engine_file · engine_symbol · notes

• value is written as the source prints it, in US customary units.
• value_si is a conversion of value with the exact NIST factors (1 lb = 0.45359237 kg, 1 ft = 0.3048 m), rounded to 4 significant digits. Where the source prints its own metric figure and it differs by rounding, notes gives it.
• source_type is one of federal_public_domain, manufacturer_datasheet, trade_association, supplier, other (university extension services, state DOT specifications, a peer-reviewed paper, a national laboratory resource).
• used_by_tool_url, engine_file and engine_symbol may hold several entries separated by ; when more than one calculator uses the same value. The two engine columns point to the site's source code, which is not part of this package.

Method

• Every value was read in the source document itself on the date in date_opened, and recorded in the site's source ledger with the passage it came from. A URL that answers is not treated as a source; the value has to be on the page.
• Only values the ledger marks verified are included. Values a calculator treats as its own editable assumption (for example the 150 lb/ft³ default for concrete) are not included.
• Ratios such as loose-to-compacted volume are arithmetic on two values of the same source row; notes shows the division.
• Building-code provisions and published tables (IRC, AWC, the Brick Industry Association's quantity tables, the CMHA grout table) are not reproduced here; the calculator pages link to them.
• No passage from any source is copied here: value, unit and link only.
• Each value was checked on 2026-09-29 against the number the calculator code holds at engine_symbol: 148 of 148 match.

How the calculators use these values is described on the methodology page.

Summary by category

By source type: manufacturer data sheet 44 · federal (public domain) 39 · trade association 37 · other 25 · supplier 3.

Calculators that read these values

Counted from the used_by_tool_url column: 19 calculator pages on takeoffmetric.com read at least one row of this table. A row that several calculators use is counted once for each of them.

Limits

• These are estimating values. Densities change with moisture, gradation and compaction; bag yields and coverage are for the named product line only. Confirm with your plans, your supplier and your local code before ordering or building.
• The condition column matters: a loose density, a bank density and a compacted density of the same material are different numbers, and using one for another changes the order quantity.
• FHWA Exhibit 5.1 A values describe highway embankment work. The calculators apply them as described in notes.

License

CC BY 4.0 for the compilation; each value remains attributed to its source. Cite as: TakeoffMetric Editorial, US Construction Estimating Constants, 2026, takeoffmetric.com. Values from federal publications are US government works; values from other publishers stay attributed to them through source_publisher and source_url.