39 lines
1.2 KiB
Markdown
39 lines
1.2 KiB
Markdown
---
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tags:
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- estimating
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---
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# Assemblies
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In [[construction-estimating-software]],
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assemblies are groups of material items
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representing a specific scope of work.
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Assemblies reduce the effort required for takeoff
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by grouping related items,
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for example 3/4" EMT connectors and couplings
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in addition to conduit.
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Assemblies allow... (in order of necessity):
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1. complex items (devices, conduit runs, etc.) with known proportions to be counted as one.
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2. changes to be made to measures and counts without recounting an entire area.
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3. takeoffs to be skimmed for obvious deficiencies that would otherwise be obscured
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4. changes to be made to project requirements (specifications) without recounting an entire area.
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If we agree on the definition of `Branch Wiring: 2#12 #12G; 3/4"C, EMT; On Structure`
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and its contents as ratios of its length,
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then their quantities can be calculated with only one measurement.
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This is how "estimating software" assembly takeoff works,
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however its a simple generic process,
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possible with several tools an estimator should be familiar with:
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* `XLOOKUP()` - Excel
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* `Table.Join` - MS Power Query
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* `JOIN` - SQL
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## Abstraction
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An abstraction is a model that intentionally ignores details
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that are irrelevant to problem it is used to solve
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