Power Plant Insulation Estimating: Deceptively Easy

August 1, 2009

Power plant insulation estimating is a lot like fishing: it looks deceptively easy, but there is a lot involved in the process.


With fishing, you always want to go after the big fish, but they are not the easiest to catch. It is the same for power plant estimating. One of my personal temptations for the power industry is the challenge and complexity of the projects. Even though projects may appear to be similar at the surface, they are usually very different, whether in schedules, crew size, manufacturers, or project location.

A major part of the temptation for many is the opportunity to catch a lot of money. The contracts can be in the range of 20 to 30 million dollars or more, depending on the scope and schedule. The schedule can range between 12 and 18 months for a complete coal-fired unit. However, during the project there are many challenges, such as keeping the project on schedule and within the estimate to ensure you do not lose money. They can be so enormous you could lose sleep over them, or you could lose sleep because you might have left several million dollars on the table during the bidding. For the insulation contractor, other challenges may include managing large crews (perhaps more than 100) to execute the challenging and complex work of insulating a boiler and the possibility of having to deal with some workers inexperienced with power plant work.

Some contractors not experienced in power plant insulation might think, “We have our steady 60 man crew that can jump onto this project.” However, power plant insulation is far more complex than it seems at first glance. Even companies that have worked in refineries for years will find the experience entirely different than working on a power plant.

Preparation and Estimating

Just like preparing for a fishing trip, many things need to happen before you actually put together your estimate (go fishing). A complete power plant insulation estimate can take anywhere from 4 to 12 man weeks to put together. You will need to execute the following:

  • Assembling bid documents and drawings. I think technology has messed up this portion of bid packages. Everything comes electronically, possibly including civil and electrical drawings. Clients can say you have all the information and should know about interferences and other potential problems.
  • Understanding scope of work documents. You may need to lay out portions of the work that may not have detailed drawings but are required per the work scope documents.
  • Understanding the specifications. Do you understand the difference between a performance specification and an installation specification? What about the wind and snow loads referenced in the specification and how they will affect the estimate? Understanding the specifications also means understanding there could be multiple specifications and how they intertwine and mesh with each of the different manufacturers involved with a power plant estimate (e.g., overall project engineer, boiler manufacturer, AQCS (Air Quality Control System) manufacturer, steam turbine manufacturer).


This is the start of the fishing trip. You need to know where you are going and what you are fishing for. A full blown power plant takeoff will consist of multiple items, and you need to understand how each item is tied to specifications. The takeoff can consist of:

  • Boiler—HRA, finned and un-finned tube wall areas, the bull nose, wind box
  • Boiler penthouse
  • Boiler equipment
  • Boiler ductwork
  • SCR
  • AQCS
  • Ductwork
  • Fans—axial vs. centrifugal
  • Steam turbine
  • BOP equipment
  • BOP piping
  • Boiler proper piping

Piping can be broken down into:

  • System piping
  • Instrumentation
  • Vents and drains
  • Personnel protection
  • Equipment penetrations/skid piping
  • Field routed piping

There are several questions to ask yourself when performing your takeoff: Do you have the interface between isometric drawings and orthographic drawings? Is there piping duplicated among the different drawings? How do the P&ID drawings affect your piping scope? Also, you might want to ask, “Do I have the interface between two vendor suppliers correct?” (e.g., between the boiler and AQCS). Are there any holes in your takeoff in the interface between the two, and who has the design responsibility for the interface?


This is equivalent to bait for our fishing trip. You will use a variety of materials on a power plant estimate. Some of these materials will consist of:

  • Mineral wool
  • Calcium silicate
  • Fiberglass
  • Ceramic fiber
  • Pourable insulation
  • Sub-girts
  • Aluminum
  • Stainless steel
  • Galvanized lagging
  • Mesh

You might even see commercial materials for anti-sweat areas in water treatment equipment and/or in administration or other operation buildings. This depends on your scope of work.

You also need to be aware of materials required to be installed on flanged pairs and valves. Will they require oversized pipe insulation, hard cover boxes with suitcase latches, or removable blankets?

Putting Together the Estimate

While fishing, you may need to adjust for the specific situation, such as weather or water clarity. You must do the same when putting together an estimate. Typically when assembling the estimate, it is assumed the work will be performed in ideal conditions. From our baseline estimated productivities, you need to adjust for:

  • Local/jobsite practices (breaks, craft jurisdiction)
  • Weather in the project’s region—will there be snow, desert heat, rain?
  • Height
  • Work area congestion (stacking of trades)
  • Access to work area (scaffold or manlifts)
  • Crew size
  • Multiple shifts

Labor is the most important piece when assembling the estimate. Ensure that you have the correct:

  • Wage rates
  • Crew mix/profile (crafts, supervision, support crew)

What type of construction work schedule will you need to work? There are all kinds of different work schedules, especially during a tightening labor market. Make sure to allow for:

  • Outages
  • Multiple shifts
  • Additional mobilizations and de-mobilizations
  • Schedule requirements/reports: What are the schedule and report submittal requirements? Is a simple bar chart enough, or do you need to use Microsoft Project or P6?

Of course, safety is the first priority. Make sure safety costs are covered in the estimate, as these costs can affect both labor cost and equipment or consumable costs.

Review the bid documents to determine whether an on-site safety manager is required. This might be a requirement once you reach a specific crew size or for the entire project. Be aware of the site meeting requirements, whether all-craft weekly meetings, daily safety pre-task analysis with all site craft employees, or daily foreman safety meetings.

As for additional safety equipment, high visibility vests may be required, or there might even be special ANSI requirements for work boots. And what about fall protection requirements for the high work that may be included?

Also when assembling the estimate, review equipment requirements closely. Equipment can be a big cost for a power plant project, depending on the scope of work. Typical equipment can be:

  • Office trailers/change shacks
  • Material hoist
  • Gators
  • Pickup trucks
  • Man lifts
  • Fork lifts—variable reach
  • Welding machines
  • Construction elevator
  • Portable toilets
  • Dumpsters
  • Scaffolding

If you self-perform or subcontract your scaffolding, it could represent 15 to 35 percent of the total application cost.

Subcontracting can play a big part of assembling the estimate. You need to understand your subcontractor’s scope of work. Typical subcontracts are:

  • Scaffolding
  • Painting
  • Refractory
  • Heat tracing

The Proposal

In fishing, this would be preparing your catch of the day either to eat or for the taxidermist. In preparing a proposal for a power plant estimate, you will typically have to prepare:

  • Bid form. These can be simple (1-2 pages) or complex (150 pages), where every drawing will have its own pricing breakout.
  • Clarifications. These can also be complex, with contractual, pricing/commercial, and technical clarifications. The biggest question is deciding whether to clarify in the proposal. If the project goes smoothly, the clarifications may never be an item of discussion. But how many power projects go absolutely smoothly?
  • Safety questionnaire/information. If your safety numbers are not adequate, you could be disqualified.

Other items typically requested in a proposal are:

  • Organizational charts
  • Project staff resumes (could include project management, supervisory, safety, clerical, and scheduler staff)
  • Work plan
  • Past project experience
  • Submittals (Material Technical Data Sheets, Material Safety Data Sheets, detail drawings)

Estimating power plant insulation is complex, and the execution is even more complex. Discussion of the execution will have to be left for another issue. Meanwhile, I hope these analogies will be useful if you embark on an estimate for power plant insulation.