Standards For Complete And Accurate HVAC Estimates

There are six important performance criteria to consider when preparing an accurate HVAC Estimate. The headings presented here are detailed in the Free Wendes Estimating Manual available for download on our web site.

1. Completeness the first rule to consider the importance of including all items in the estimate that are integral parts of the system based on industry standard practice and all accessory items.

2.Valid Size Ranges For materials when size ranges are used for an estimate there should be a valid correlation with the average size range for the group of materials used for the project. The broader the size range used the greater likelihood of inaccuracy.

3. Correct Quantity Units, scales and quantities must be as correct as possible.  Are the correct number of units included along with the correct scale for lengths being quantified? 

4. Correct Labor Hours one of the most difficult areas is including the correct labor hour variances for the project. The size ranges, material handling and variations in fabrication and installation need to be considered.

5. Material Pricing the pricing for raw materials, equipment and sub contract work should be detailed. Taking the time to obtain valid material cost is essential along with vendor reliability, comparisons, performance and exclusions.

6. Math Extensions and Summations an area of subtle miscalculation occurs in the estimate summary columns on the takeoff, extensions, summary and recap sheet. These are all areas for mathematical  error.