Having worked on both sides of the design and build business segments, I thought I’d share my own experience with how estimators and contractors, along with the in-the-field workforce, can contribute to the optimum HVAC system design when working with the consulting engineer as a team. 

Now, this in not a “knock” on consulting engineers, but, instead, it is a voice of encouragement to both consulting design engineers and HVAC contractors committed to providing the best, most affordable HVAC solutions possible. Teamwork is always better because of several factors that include a team effort to achieve “best practice” of the design, construction, and eventual operation and maintenance of an HVAC solution.

Right away, I believe I’m correct in saying the stand-alone consulting engineer does not have his or her pulse on the HVAC industry as it pertains to the cost to furnish and install a system design. Follow this up with the knowledge that there is equally as much that goes into the construction of a system as there is to designing it. Here is where teamwork comes together.

Based on my years of design engineering, I feel confident I could engineer a near-perfect HVAC system. Once complete, I’d qualify my statement by saying that I’m sure an experienced contractor could take my “perfect” design and make it better. My point to this example is that until I actually went to work for an HVAC contracting company, I never truly absorbed the amount of work it took to be proficient with estimating and construction. Now, I believe one is naive to think a designer may know as much as the estimator or the builder. 

Whether you call it design-build (D-B) or integrated project delivery (IPD), the hidden word is “teamwork.” Teamwork helps draw out each individual’s expertise because, while the designer is designing, other things are happening at the estimator’s workstation as well as the contractor’s job site. 

Starting with the estimator:

1. What discount percentage is currently available for estimating the purchase of equipment and subcontractor services?
2. What is the current available workforce cost, e.g., business is slow versus very busy and associated costs impact?
3. Will the designer accept the estimator’s suggested value-added options in lieu of the design specification, e.g., soldered copper pipe versus welded pipe?
4. Will the designer accept the estimator “packaging” the equipment, e.g., the majority of the equipment comes from one equipment manufacturer representative’s line card of equipment versus separating the purchases to a number of different manufacturer representatives? 
5. What is the equipment delivery time versus the project schedule, and will the designer accept a fast-track equipment alternative?
6. Without existing condition drawings, will the designer accept the estimator carrying an allowance to draw down on versus estimating the labor cost to cover existing condition obstructions?

While these are a few of the estimator questions and concerns, here are a few installing contractor questions and concerns:

1. Can the contractor solicit other equipment manufacturer quotes even though they would come from manufacturers not in the contract specification?
2. Will the available workforce be willing to have some say on the qualifications of the laborers coming on-site?
3. Will the designer consider a different type of HVAC system based on the contractor’s experience with the project’s conditions, e.g., difficulty to furnish and install a central air sheet metal system versus an alternate piping system?
4. Will the designer consider a competitively bid three-year service contract from a contractor in lieu of a more traditional one-year warranty?
5. Will the designer accept different materials once construction starts and existing condition obstacles occur, e.g., rectangular sheet metal versus round or flat oval ductwork?
6. Will the designer consider providing the operation and maintenance system training versus trade contractors and/or technician instructors?

With D-B and IPD project delivery methods, the client will be the one who will most benefit from teamwork between the designer, estimator, and contractor, while all three will inherently learn from each other. It can’t be helped because communication along with listening and letting “consensus” lead the way are the foundation to the optimum HVAC solution process.