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Different Points of Estimating View

Training estimators in many markets gives me an interesting insight into how each group sees their work. Each has the challenge to get the job done quickly, accurately and efficiently. For some it means preparing an estimate from concept to budget, while for another it means following process and procedure as spelled out in highly detailed and complex requirements. Each is comfortable in his/her own context and particular market.

There are four main markets that have been identified:

  1. Residential
  2. Commercial
  3. Industrial
  4. Fabrication

All need to calculate cost of moving liquid or gas from point A to B using pipe and fittings.

RESIDENTIAL HIGH-RISE/ MULTI-FAMILY

Fast and cheap is the motto for this group. If there is a way to speed up the estimating process, they will consider it. Residential and commercial high-rise condominiums and hotels are the specialty here.

The project specifications for this group are usually similar to commercial construction. There are many similarities between commercial and large residential building mechanical systems.

Initial budget drawings can be limited to unique layouts that repeat except for unique spaces like mechanical rooms and special floors. (First and Penthouse) Budgeting will typically be done based on fixture count, suite, or floor. Value engineering to trim costs is often welcome

Repetition is very common so accuracy is important since any mistake either plus or minus will be repeated by the occurrence.  Innovative products that speed up installation are a focus for project managers who want to beat the labor. Therefore product knowledge and incorporating new technique into estimating are important. Estimators must know the local plumbing codes and techniques in the location of the project; they can be very different from one city to another.

Many high rise contractors fabricate floor to floor risers and repetitious branch assemblies to speed up production. This requires planning usually based on floor level basis for material and manpower. Estimating separate shop and field is a competitive advantage.

As the project progresses, labor productivity accelerates when floor layouts are learned and are easy to build. After about the 10th floor however, production tappers off because of the wait times for hoisting material and manpower. This needs to be considered for accurate estimating.

Types of projects include: High rise condominiums, high rise hotels, high rise offices, Low rise multi- family, retirement homes/ complexes, low rise hotels.

COMMERCIAL

Commercial contractors are most often involved with unique buildings although box stores and strip malls can be thrown in with hospitals and any other large unique structures.

Commercial construction has many governing authorities which will be spelled out in detail within the standard format specifications.  Standard format is in transition now and is still rolling out. There is a place for everything in the new format but it can be a challenge finding pertinent details until you learn to navigate the mass of information. Drawings are often incomplete but since this is not new, it should be expected that the estimator will fill in the gaps.

Budgeting is difficult due to limited repetitive nature of the work. Often several methods are needed to get a sense of cost.  Square footage for similar projects is often used. Total equipment capacity like heating and cooling based on hydronic or air delivery. Combine that with a cost per fixture for plumbing and some creative, knowledge based costs and they can get very close.

Until BIM is perfected, engineers will use the talents of the commercial estimator to complete the design, and come up with cost saving value engineering. The trade based estimator works well with this mix. A (new) engineering based estimator will have to be taught were to look for the gaps and how to correctly fill them.

Depending on the diversity of projects a contractor pursues, the estimator must become familiar with many types of systems. Hospitals are a place of diverse piping systems supporting plumbing, heating, and process systems like medical gas, laboratory, steam, and condensate. If skills to estimate and/ or install some of these are not “in-house”, they will need to be subcontracted to specialists to complete the scope of the work.

Project scope crossover must be searched out. For example, supply of motor starters and wiring to mechanical equipment may be part of the mechanical scope. Old Division 11 equipment supply and or install may be in the mechanical scope on treatment plant projects.

Types of projects include: Hospitals, schools including colleges and universities, community centers, government facilities and institutions, commercial office and industrial buildings, warehouses, shopping malls and retail stores, restaurants, airports, water and waste water treatment and many more. Within these structure types, there are many different areas of expertise that specialists gravitate to.

INDUSTRIAL

Multi-trade coordination is the challenge for many industrial estimators. Often steel structures, electrical, millwrighting, and concrete work are included in the mix of mechanical contracts. Many specialized systems with exotic process materials and unique skills needed to install them must be well understood.

Project requirements are not always standard format like commercial work. Details unique to the project processes will be included on P&ID as well as isometric detail drawings. Research and consultation to understand complex systems may be required before the real cost of completing the work can be determined. Large equipment installation connecting to piping must be carefully researched if it is included in the scope of work.

Budgeting methods for industrial work can be difficult since so many unique processes with many types of material don’t lend themselves to trending costs. Often the way to budget is by cost per foot of pipe and fittings, diameter inches of weld, or even total weight of the pipe work.

Experience in the field is very important since understanding the work plus the unique requirements of the client have to be combined. The cost of access and safety requirements may make up a significant part of the labor costs.

Some companies require project managers to estimate their own work. This keeps the knowledge of the job with a single person. The advantage is that the job gets learned once, and all the components, whether built in-house or by a subcontract, have a central contact with full knowledge of the project.

Larger projects will be spread out with many estimators working on specialized components. Fabricators may be engaged to prepare special or large quantities of pipe and fitting components for installation on site.

Types of projects include: manufacturing, refinery, processing, power generation, and mining. Here there will be specialists in specific processes or market sectors.

FABRICATION

Fabricators, by and large, simply manufacture the pieces of pipe in small sections called spools that can be either bolted or welded to each other on site. The pieces need to fit on trucks for delivery to site. Some fabricators build “modules” for shipment to site. These can be the size of a house, transported and lifted into place to join to other modules with pipe ends ready to connect.

Drawings can be isometric details of entire plants numbering in the hundreds. The pipe and fitting specifications are very detailed with many engineering rules rather than local codes. Every detail of the material and weld procedures to be used is spelled out in detail with very little room for interpretation and substitution.

Fabricators often use the “diameter inch” of weld to get a read on the size of a project. They may be requested to submit preliminary budgets based on diameter inches. The rough cost of those inches is calculated plus the weight of the pipe and fittings to come up with a rough estimate. This may or may not be factored diameter inches which will start from a base line and be factored according to wall thickness, alloy, and complexity.

Cost of quality assurance, rework, non-destructive testing like X-rays, and pre and post weld heat treatment for some alloys must be included. Knowing when to add for these is part of the experience required for accurate estimates.

The detail for industrial fabrication can be daunting for the un-initiated. For example, some subcontract the fabrication of pipe supports since each one can be uniquely engineered with a different size based on pipe, insulation thickness as well as material compatible to the pipe it supports.

Understanding the language is part of learning the craft of fabrication. There are many terms and acronyms used that most estimators never encounter unless they venture into this specialty.

Types of projects include: power plant, oil refinery, and mining. This is a short list but there are numerous subdivisions of each type.

Even though the estimators in all the four market categories are essentially doing a similar calculation of material and labor cost, the angles of approach are very different. Residential and some commercial estimators attack the estimate using repetitive techniques with all automatics like hangers, joints, insulation etc. turned on for speed. The fabricator, on the other hand, counts every detail employing none of the speed options in pursuit of accuracy. These extremes are understandable when you look at the value of the work. While a few fittings more or less makes little difference to a commercial project with subcontracts and equipment packages, the value of industrial components and the labor required to make a joint can be astronomical.

Coming from the middle ground of commercial/ light industrial markets and seeing the skills and techniques used by estimators in diverse market sectors gives me a lot of respect for the estimators I encounter. Some are highly specialized and focused while others possess great diversity of experience and knowledge. All have one or more vantage points from where they approach their craft.