What Are Cost Item Assemblies in Construction Estimating Software?
June 28, 2021
When it comes to construction, a structure isn’t just a structure. It’s the sum of myriad components. A wall for example, might consist of drywall, studs, screws, tape, spackling paste, paint and more, as well as the labor that goes into making it a finished wall. Collectively, these form a cost item assembly — the line items that define both the materials and their costs to complete a unit of construction work.
These assemblies help form the root of your estimates. And when working on projects that involve seemingly countless materials, such as those with a sizable footprint and perhaps multiple structures, inputting these assemblies into construction estimating software will help streamline an otherwise complicated estimating process. You can create your own or import a predefined cost item assembly from a third-party library into your software.
How is a cost item assembly calculated? It multiplies the takeoff number of units (one unit is made up of all the individual component line items) by the cost per unit to yield the total cost and required materials. Estimating software does the math for you; all you need to do is enter the number of units.
What cost item assemblies include
There are going to be certain elements that are replicated throughout a single project and across similar ones — such as walls, doors, and windows, for example, of a particular type and size. Each of these depends on a predictable set and quantity of components to install them. This forms the assembly.
Let’s go back to the wall from the beginning and what it would take to construct one unit of work — we’ll use one linear foot of an 8’ high interior wall as our unit of measure. Your cost item assembly would include the exact length of drywall, number of screws and studs, linear feet of tape, volume of spackling paste, volume of paint, and so on, plus the cost of each item (all expressed as a percentage or ratio) to complete just one unit. You will likely have several line items to account for how long it takes for the different kinds of labor to do painting, hanging, taping, etc.
Your project could also include office doors that are of a standard size. Each door assembly requires items such as the door, frame, head jamb, side jambs, sill, hinges, handle, lock, strike plate, nails, screws and labor hours to install it.
Without assemblies, you’d be stuck tediously costing out each individual nut and bolt. But you can save yourself the time and effort by simply entering the quantity for each assembly from the takeoff into the estimating software. So for the wall it would be the linear feet of interior wall, and for the doors it would simply be the number of door assemblies. The software then tallies the total number of components and costs, making materials and labor estimating and procurement much simpler and more accurate.
What about costs for materials and labor that are bound to fluctuate from project to project? With construction estimating software there’s no repetitive unit price updating of each individual component. Once you adjust the price in the database, the software reflects that component’s cost throughout all assemblies and updates calculations automatically.
Why are cost item assemblies used in estimating software?
They produce detailed cost item listings of the project scope for increased reliability of cost input.
Assemblies create an easy, replicable and repeatable method in the already-complex estimating process. They can be developed by your own construction company, or they can be downloaded from third-party libraries (with some even being built into some software options). The result is greater consistency and efficiency.
They lower the risk of individual components being overlooked and unaccounted for, ensuring a more thorough scope of work and a more accurate estimate.
What are the benefits?
If you’re often building the same kinds of walls and windows, for instance, you’ll save time during takeoff by storing frequently used assemblies that can be used for future projects.
Effortlessly modify line items based on project requirements (such as for unique or unusual considerations), material and equipment cost variables that waver over time, and productivity levels. The estimating software then automatically adjusts related assemblies.
Having pre-built assemblies streamlines the complex estimating process into something less time-consuming, more manageable and more consistent.
Whether you’ve created your own assembly library or imported an assembly database from elsewhere, having these stored in your estimating software enables you to standardize your estimating process as well as the estimates themselves.
This standardization that relies on pre-built assemblies can only lead to increased confidence in the thoroughness and accuracy of your estimates.
With cost item assemblies being such a critical element in estimate preparation, especially for capital projects, it makes sense to adopt a construction estimating software that can handle limitless assemblies and make your process more predictive. InEight Estimate is a solid software option to consider. And yes, it allows you to build cost item assemblies that harness the values, formulas and logic you define that make sense for the projects you work on. Request a demo to see how it also optimizes your estimating process so you can prepare more complete, competitive bids.