When estimating materials in the Estimating Workbook, Size, Units, Unit Cost, Quantity, and Waste must all be calculated and accounted for. It is vital to understand what each of these terms mean in the context of construction estimating.
Size | The amount of material included in a single unit purchased from a supplier. |
Unit | The way material is measured and sold by a supplier. Examples include linear feet, cubic yards, complete units, square feet, etc. |
Unit Cost | How much a single unit of the material costs to purchase from a supplier. |
Quantity | The number of items required to complete a specific construction task based on the quantity takeoff from the building plans. |
Waste | The percentage of material that is anticipated to be unused or unusable due to error or unforeseen circumstances. |
You plan to host a party to watch a sporting event on television with friends. Seven people will be present, including yourself.
You will provide beverages to your guests, who all prefer the same soft drink. You anticipate that over the course of the event, each person will drink three soft drinks. You know from experience that some of your guests will not finish their drinks, and that some may drink more than three.
You go to the store, and find that the soft drink is only sold in packages of six cans for $3.50 per package. You decide to purchase four packages of soft drinks. If you were to use the construction estimating definitions of the terms above, they would fit this example as follows:
The Size is listed as 6 because the Unit is defined as cans/pk. If the Unit were defined as pack, the Size would be 1. This is problematic because you might not know how many cans are included in a pack, which is why the Unit is defined as cans/pk.
You intend for each of the seven attendees to drink three soft drinks. If you purchase four packages of six cans, you will have 24 total cans for the event. This is the minimum you must purchase to provide three cans to each attendee, and there should be three cans left over. This is why the Quantity is listed as 4.
You need a new pair of shoes. You go to the store and find a pair that you like. It costs $65.00. If you were to use the construction estimating definitions of the terms above, they would fit this example as follows:
In the above example, you have two feet, which require one pair of shoes. The Size is 1 because the Units define shoes as being sold in pairs. You cannot purchase shoes individually. Given your need and the Units at which shoes are sold, you require 1 unit, which is 1 pair. This is why the Quantity is listed as 1.
Size, Units, and Unit Cost are defined by the suppliers from which you purchase your construction materials. Because of this, the Estimating Workbook includes supplier and material databases that must be referenced when estimating materials for a construction project.
The formula used to calculate Size will use the following definitions:
IF(material_cell=””,0,VLOOKUP( material_cell,database_name,column_in_database,FALSE))
Reading the above formula in layman’s terms would be something like this.
IF(material_cell=”” | If the material cell is blank. |
,0 | Display 0 |
,VLOOKUP | If the material cell is not blank, do a VLOOKUP function. |
(material_cell | Look for the material named in the material cell |
,database_name | In the database I have chosen. |
,column_in_database | In the column of the database I have specified. |
,FALSE)) | The database must return an exact match. |
You are completing the Stair Framing Materials section of the Estimating Workbook.
Size, Units, and Unit Cost are defined by the suppliers from which you purchase your construction materials. Because of this, the Estimating Workbook includes supplier and material databases that must be referenced when estimating materials for a construction project.
The formula used to calculate Units will use the following definitions:
IF(material_cell=””,0,VLOOKUP(material_cell,database_name,column_in_database,FALSE))
Reading the above formula in layman’s terms would be something like this.
IF(material_cell=”” | If the material cell is blank. |
,0 | Display 0 |
,VLOOKUP | If the material cell is not blank, do a VLOOKUP function. |
(material_cell | Look for the material named in the material cell |
,database_name | In the database I have chosen. |
,column_in_database | In the column of the database I have specified. |
,FALSE)) | The database must return an exact match. |
You are completing the Stair Framing Materials section of the Estimating Workbook.
Size, Units, and Unit Cost are defined by the suppliers from which you purchase your construction materials. Because of this, the Estimating Workbook includes supplier and material databases that must be referenced when estimating materials for a construction project.
The formula used to calculate Units will use the following definitions:
IF(OR(material_cell=””,supplier_cell=””,0, VLOOKUP(material_cell,material_database_name, MATCH(supplier_cell,supplier_list_name,0),FALSE))
Reading the above formula in layman’s terms would be something like this.
IF(OR(material_cell=””,supplier_cell=”” | If the material cell or the supplier cell is blank |
,0 | Display 0 |
,VLOOKUP | If neither the material cell nor the supplier cell is blank, do a VLOOKUP function. |
(material_cell | Look for the material named in the material cell. |
,material_database_name | In the database I have chosen. |
,MATCH(supplier_cell,supplier_database_name, | And pull the information from the column that matches the defined supplier in the named array for material suppliers in the database. |
,FALSE)) | The database column has to return an exact match. |
You are completing the Stair Framing Materials section of the Estimating Workbook.
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