From concrete formwork walls to consumables

A worked example of the Global Variables methodology in US customary units. Concrete Formwork, Walls is the hero resource here: an installed rate for wall formwork priced entirely from linked resources, tracing down through a materials resource to the individual consumables used on site.

This addendum applies the same dependency-graph principle described in the main paper to a US customary example, priced in square feet, linear feet, and board feet rather than meters and cubic meters. The hero resource is Concrete Formwork, Walls: an installed rate covering the labor to erect, strip, clean and move the forms, plus the materials to supply and fabricate them. That rate does not price its own materials, it calls a formwork materials resource. That materials resource does not price its own consumables, it calls a consumables resource. Three spreadsheets, one live chain, sized here to a 4,000 SF wall job, and every figure below is the model as it runs.

The hero resource: Concrete Formwork, Walls

Everything else in this addendum exists to price this one resource. It is built for a 3-person crew working at 13 SF per hour, assumes the formwork is reused 6 times before it is written off, and adds a 5% waste allowance on top. Scaled to an example 4,000 SF wall job, that comes to a job total of $60,189.27.

The chain, wall to consumable

Reading top to bottom: each card is a full Global Variables resource in its own right, and the line joining it to the card below is not a copied number, it is a resource reference. Change the price of a single consumable and the materials rate moves, and the installed wall formwork rate moves with it. Click any card to jump straight to its full build-up.

The hero resource also calls LAB-03 | Concrete, Building, a $46.51/hr labor rate, three separate times (erect and strip, clean and move, and fabricate). That labor resource is itself a further Global Variables build-up, priced elsewhere, and is not expanded in this addendum.

Zooming into the hero: labor vs. materials

The $15.04/SF installed rate breaks into four contributing rates: two labor operations, a fabrication labor allowance, and the materials line that hands off to the next resource in the chain.

The full build-up, resource by resource

Each tab below is one exported Global Variables resource, the same three spreadsheets shown in the chain above, in the same order, with every group and line item intact. The hero resource carries an extra pair of columns, Rate and Amount, because it extends its per-square-foot rate out to the 4,000 SF example job; the materials and consumables resources price a plain rate per unit. A resource line highlighted in blue is a pointer to an entire second sheet rather than a hardcoded price.

Reading the variable codes

Each bracketed code is a live pointer into its own resource, not a copied figure. The codes below are used within the hero and materials resources; the one global variable in this chain, WHD_GV, is shared with every other resource in the Global Variables model, including the metric examples elsewhere in this series.

Why this matters beyond one rate

The reuse factor and the waste factor in the hero resource, 1 in 6 uses and 5%, are exactly the kind of assumption that is easy to bury in a spreadsheet and hard to find again. In the Global Variables model they are named, visible rows: change the number of uses a form set is expected to survive, and the materials contribution to the installed rate recalculates immediately, with no need to re-key the fabrication line or the job total.

Scale that from one wall formwork rate to a full estimate with hundreds of assemblies, and the same pattern repeats: a lumber price change flows from the consumables and materials resources straight through to every wall, column, and slab formwork rate built on them, in both the US customary units shown here and the metric units used elsewhere in this series.