Phoenix, Arizona (December 2009)
Estimating Construction Testing and Inspection Services
By Bryan R. Castles, PE, Principal / Senior Materials Engineer
Western Technologies, Phoenix, Arizona
From an article prepared for The Addenda News, the Quarterly Publication of The American Society of Professional Estimators, Chapter 6, Phoenix, Arizona —
In order to estimate testing and inspection services for projects, it is helpful to first understand the internal cost structure of the testing and inspection company, typical fee structures, and the various methods used to prepare estimates. Knowledge of these items leads to understanding why estimates are what they are and is beneficial in obtaining comparable estimates for projects.
The cost for testing and inspection services generally range from 0.4% to 1.5% of the total construction cost. It is not uncommon for estimated testing and inspection costs to be significantly different from the actual cost. These variations are the result of estimating methods and fee structures.
The internal cost structure for testing and inspection companies is practically the same for all companies in a geographic area. Labor accounts for nearly 50% of the companies' direct expenses. Vehicle costs are the next largest direct expense at about 7%. The table illustrates a typical cost structure for a testing and inspection company.
If the cost structures of the companies are similar then the fees charged on a project should also be similar. There are various fee structures used in the industry, but at the end of the day, the total fee for similar services should be similar; but the value added by knowledgeable firms that are willing and able to help you resolve issues and solve problems is not.
Fee structures can be simple or complex. A simple fee structure would include an hourly rate for field personnel, per test rates for laboratory testing, charges for the vehicle and equipment, and an hourly rate for engineering services. Variations of this type of fee structure may include things like daily equipment fees, daily management and engineering fees, project administration fees, clerical fees, copying fees, and minimum charges. The bottom line is that for a given service, the fees charged by testing and inspection companies should be comparable.
In addition to the variation in fee structures, the methods used for estimating a total fee for a project vary. Common methods include using a percentage of the total estimated construction costs; detailed takeoff of quantities and guesses of durations and production rates; overall duration of the project; or various combinations of the all of these. Each of these methods should arrive at nearly the same total fee for a project; however each relies on assumptions made by the estimator. These assumptions may or may not be based on fact. A scope of services should at least put quotes on a comparable basis, but that is not always the case.
Because of the various fee structures and the methods used to estimate total fees, a wide range of estimates may be received for the same project. These estimates will, quite often, be lower than the actual fees billed for a project. On a recent project here in Phoenix, 14 companies submitted estimates ranging from $75,000 to $1,070,000. Plainly these estimates are not comparable even though there was a common bid form.
The estimates vary for several reasons. The schedules and durations assumed by the testing and inspection company are optimistic or impossible. Retesting, delays, and cancellations are not included in the scope but do occur on most jobs. In other words, the quoted scope is often an idealistic scenario that may be far from actuality.
So how does one obtain competent proposals in a form that can be easily compared? Step 1 is to develop and use proposal and bid forms. Step 2 is provide realistic quantities, schedules, and durations to put proposals and estimates on comparable ground and, Step 3, demand simple fee structures. Of course, maintaining an open dialogue greatly helps to keep testing and inspection costs in line with estimates and actual requirements. With some upfront planning and minimal, but critical, input to the testing and inspection company, comparable quotes are obtainable.
*****Phoenix, Arizona (February 2009)
The Biggest Environmental Misconception
By Vicky L. Aviles, AEP, CIAQM
Principal / Senior Environmental Scientist
Western Technologies, Phoenix, Arizona
From an article prepared for AZ Development Central (A web publication at azdevelopmentcentral.com), Volume 2, Issue 5 —
The biggest environmental misconception may be placing you, your employees, your clients and families at risk for exposure to asbestos and vulnerable to regulatory noncompliance violations. The general belief that the use of asbestos fiber in building materials has been banned by the Environmental Protection Agency (EPA) is not correct. In fact, you don't need to conduct extensive research to figure this one out. Just go to the EPA's website. Yet renovation, tenant improvements (TIs), and demolition work in buildings is conducted daily without regard to these exposure potentials. Building materials that are not glass, metal or wood and regardless of year of construction are asbestos-containing until sampled and analyzed in accordance with the EPA's AHERA protocol to prove otherwise.
The State of Arizona asbestos program is handled through the Arizona Department of Environmental Quality (ADEQ) and has jurisdiction in all counties with the exception of Maricopa, Pima and Pinal. These counties (Maricopa, Pima and Pinal) have delegated authority from the EPA to enforce the Asbestos NESHAP regulations and have additional requirements above and beyond the federal standards.
Building materials may be assumed to contain asbestos; however a negative assumption for asbestos would not be compliant with the existing regulations. All facilities, with the exception of single-family residences, are required to be evaluated by an EPA-accredited inspector for asbestos prior to disturbance and a NESHAP notification is mandatory if regulated activities are to occur.
*****Phoenix, Arizona
The Use of Asphalt-Rubber Binder Design Profiles
By Phillip D. Feliz, SET, Principal / Senior Materials Professional
Western Technologies, Phoenix, Arizona
Over the years, both agency and industry have developed a system to quantify the engineering properties of asphalt-rubber binders (ARB) using standard tests in accordance with ASTM. The standard practice in A-R binder design is to evaluate the ARB stability and retention of properties over a 24 hour period, usually at three interaction periods, in a “design profile”. This profile identifies the ARB's ability to remain stable after completion of field mixing and in the event of a job delay. A profile conducted on a binder used recently on an Arizona Department of Transportation (ADOT) project is provided in the following Typical ARB Profile example.
Other agencies may require more tests and at additional times, but ADOT's requirements cover, in my opinion, the most important properties for a successful ARB.
ARB for hot mixes and friction courses can tolerate higher viscosity (increased crumb rubber) which can result in thicker films of ARB on the aggregate, higher binder contents enhancing durability, and fatigue resistance properties of both mixes. The following are typical mixture binder contents and related film thickness in microns:
Holding material for too long or at high temperature can cause the rubber particles to dissolve, especially if the crumb rubber contains a high percentage of natural rubber. A large drop in viscosity within a short time period can indicate the loss of rubber particles and affect a loss in film thickness or drain down in a mix and crack resistance.
Spray applied ABR (SAM and SAMI), on the other hand, can be difficult to spray at viscosities above 2500 centipoises. In addition, the resilience of the ARB should be evaluated for SAM application. There has been concern of losing aggregate chips, because the resilience was too high. Some in the industry feel that a maximum resilience of 50 percent may need to be specified to minimize chip loss. High resilience should not detrimentally affect the SAMI since an overlay is planned.
In the past, coarse graded crumb rubber was widely used for spray applied ARB. These coarse gradations required high amounts of crumb rubber additions (20 to 22%) to achieve the minimum viscosity. However, the viscosity usually increased through continued reaction and diluents, such as kerosene, was required to reduce the viscosity for adequate spray application.
The use of diluents has become unpopular with the more stringent air quality requirements, and should not be used during SAM, SAMI, AR-ACFC, and hot mix applications. The industry is finding that finer crumb rubber gradation, such as the ADOT Type B illustrated below is resulting in better chip adhesion and has eliminated the need for use of diluents.
Estimating Construction Testing and Inspection Services
By Bryan R. Castles, PE, Principal / Senior Materials Engineer
Western Technologies, Phoenix, Arizona
From an article prepared for The Addenda News, the Quarterly Publication of The American Society of Professional Estimators, Chapter 6, Phoenix, Arizona —
In order to estimate testing and inspection services for projects, it is helpful to first understand the internal cost structure of the testing and inspection company, typical fee structures, and the various methods used to prepare estimates. Knowledge of these items leads to understanding why estimates are what they are and is beneficial in obtaining comparable estimates for projects.
The cost for testing and inspection services generally range from 0.4% to 1.5% of the total construction cost. It is not uncommon for estimated testing and inspection costs to be significantly different from the actual cost. These variations are the result of estimating methods and fee structures.
The internal cost structure for testing and inspection companies is practically the same for all companies in a geographic area. Labor accounts for nearly 50% of the companies' direct expenses. Vehicle costs are the next largest direct expense at about 7%. The table illustrates a typical cost structure for a testing and inspection company.
| Direct Labor | 50% | Burdened Field, Laboratory, Direct Support Personnel |
| Vehicles | 7% | Vehicle, Fuel, and Maintenance |
| Other Direct | 8% | Supplies, Testing Equipment, Certification, Training, and Accreditation |
| Indirect | 15% | Indirect Management, Administrative Support, Facility Rent, Telephones, Copiers, etc. |
| Corporate Overhead | 10% | Health and Safety, Errors and Omissions Insurance, Auto, Liability, Property Insurance, Human Resources, Legal |
| Net Before Taxes | 10% |
If the cost structures of the companies are similar then the fees charged on a project should also be similar. There are various fee structures used in the industry, but at the end of the day, the total fee for similar services should be similar; but the value added by knowledgeable firms that are willing and able to help you resolve issues and solve problems is not.
Fee structures can be simple or complex. A simple fee structure would include an hourly rate for field personnel, per test rates for laboratory testing, charges for the vehicle and equipment, and an hourly rate for engineering services. Variations of this type of fee structure may include things like daily equipment fees, daily management and engineering fees, project administration fees, clerical fees, copying fees, and minimum charges. The bottom line is that for a given service, the fees charged by testing and inspection companies should be comparable.
In addition to the variation in fee structures, the methods used for estimating a total fee for a project vary. Common methods include using a percentage of the total estimated construction costs; detailed takeoff of quantities and guesses of durations and production rates; overall duration of the project; or various combinations of the all of these. Each of these methods should arrive at nearly the same total fee for a project; however each relies on assumptions made by the estimator. These assumptions may or may not be based on fact. A scope of services should at least put quotes on a comparable basis, but that is not always the case.
Because of the various fee structures and the methods used to estimate total fees, a wide range of estimates may be received for the same project. These estimates will, quite often, be lower than the actual fees billed for a project. On a recent project here in Phoenix, 14 companies submitted estimates ranging from $75,000 to $1,070,000. Plainly these estimates are not comparable even though there was a common bid form.
The estimates vary for several reasons. The schedules and durations assumed by the testing and inspection company are optimistic or impossible. Retesting, delays, and cancellations are not included in the scope but do occur on most jobs. In other words, the quoted scope is often an idealistic scenario that may be far from actuality.
So how does one obtain competent proposals in a form that can be easily compared? Step 1 is to develop and use proposal and bid forms. Step 2 is provide realistic quantities, schedules, and durations to put proposals and estimates on comparable ground and, Step 3, demand simple fee structures. Of course, maintaining an open dialogue greatly helps to keep testing and inspection costs in line with estimates and actual requirements. With some upfront planning and minimal, but critical, input to the testing and inspection company, comparable quotes are obtainable.
*****Phoenix, Arizona (February 2009)
The Biggest Environmental Misconception
By Vicky L. Aviles, AEP, CIAQM
Principal / Senior Environmental Scientist
Western Technologies, Phoenix, Arizona
From an article prepared for AZ Development Central (A web publication at azdevelopmentcentral.com), Volume 2, Issue 5 —
The biggest environmental misconception may be placing you, your employees, your clients and families at risk for exposure to asbestos and vulnerable to regulatory noncompliance violations. The general belief that the use of asbestos fiber in building materials has been banned by the Environmental Protection Agency (EPA) is not correct. In fact, you don't need to conduct extensive research to figure this one out. Just go to the EPA's website. Yet renovation, tenant improvements (TIs), and demolition work in buildings is conducted daily without regard to these exposure potentials. Building materials that are not glass, metal or wood and regardless of year of construction are asbestos-containing until sampled and analyzed in accordance with the EPA's AHERA protocol to prove otherwise.
The State of Arizona asbestos program is handled through the Arizona Department of Environmental Quality (ADEQ) and has jurisdiction in all counties with the exception of Maricopa, Pima and Pinal. These counties (Maricopa, Pima and Pinal) have delegated authority from the EPA to enforce the Asbestos NESHAP regulations and have additional requirements above and beyond the federal standards.
Building materials may be assumed to contain asbestos; however a negative assumption for asbestos would not be compliant with the existing regulations. All facilities, with the exception of single-family residences, are required to be evaluated by an EPA-accredited inspector for asbestos prior to disturbance and a NESHAP notification is mandatory if regulated activities are to occur.
*****Phoenix, Arizona
The Use of Asphalt-Rubber Binder Design Profiles
By Phillip D. Feliz, SET, Principal / Senior Materials Professional
Western Technologies, Phoenix, Arizona
Over the years, both agency and industry have developed a system to quantify the engineering properties of asphalt-rubber binders (ARB) using standard tests in accordance with ASTM. The standard practice in A-R binder design is to evaluate the ARB stability and retention of properties over a 24 hour period, usually at three interaction periods, in a “design profile”. This profile identifies the ARB's ability to remain stable after completion of field mixing and in the event of a job delay. A profile conducted on a binder used recently on an Arizona Department of Transportation (ADOT) project is provided in the following Typical ARB Profile example.
| Test | Minutes of Reaction | Specification Limits at 60 Minutes | ||||
| 60 | 90 | 135 | 240 | 1440 | ||
| Viscosity, CpHaake at 190°C (350°F) | 1900 | 2300 | 2700 | 2800 | 4000 | 1500 to 4000 |
| Resilience at 25°C (77°F) (% Rebound) ASTM D5329 | 35 | — | 43 | — | 38 | 20 Minimum |
| R&B Softening Point, °F ASTM D36 | 145.0 | 146.0 | 148.0 | 145.5 | 145.5 | 130 Minimum |
| Penetration at 4°C (39.2°F) 200 grams, 60 seconds, ASTM D5 | 29 | – | 28 | – | 34 | 15 Minimum |
Other agencies may require more tests and at additional times, but ADOT's requirements cover, in my opinion, the most important properties for a successful ARB.
ARB for hot mixes and friction courses can tolerate higher viscosity (increased crumb rubber) which can result in thicker films of ARB on the aggregate, higher binder contents enhancing durability, and fatigue resistance properties of both mixes. The following are typical mixture binder contents and related film thickness in microns:
| Dense Graded 4.6% | Hot Mix Asphalt | 9 micron |
| Gap Graded 7.4% | Asphalt Rubber | 18 micron |
| Open Graded 9.2% | Asphalt Rubber | 36 micron |
Holding material for too long or at high temperature can cause the rubber particles to dissolve, especially if the crumb rubber contains a high percentage of natural rubber. A large drop in viscosity within a short time period can indicate the loss of rubber particles and affect a loss in film thickness or drain down in a mix and crack resistance.
Spray applied ABR (SAM and SAMI), on the other hand, can be difficult to spray at viscosities above 2500 centipoises. In addition, the resilience of the ARB should be evaluated for SAM application. There has been concern of losing aggregate chips, because the resilience was too high. Some in the industry feel that a maximum resilience of 50 percent may need to be specified to minimize chip loss. High resilience should not detrimentally affect the SAMI since an overlay is planned.
In the past, coarse graded crumb rubber was widely used for spray applied ARB. These coarse gradations required high amounts of crumb rubber additions (20 to 22%) to achieve the minimum viscosity. However, the viscosity usually increased through continued reaction and diluents, such as kerosene, was required to reduce the viscosity for adequate spray application.
The use of diluents has become unpopular with the more stringent air quality requirements, and should not be used during SAM, SAMI, AR-ACFC, and hot mix applications. The industry is finding that finer crumb rubber gradation, such as the ADOT Type B illustrated below is resulting in better chip adhesion and has eliminated the need for use of diluents.
| Sieve Size, % Passing | ADOT Type B |
| 2.00 mm (No. 10) | 100 |
| 1.18 mm (No. 16) | 65 – 100 |
| 600 µm (No. 30) | 20 – 100 |
| 300 µm (No. 50) | 0 – 45 |
| 75 µm (No. 200) | 0 – 5 |
Contact
Bruce Mac Ilroy PE
Principal Geotechnical Engineer
(602) 437 3737
Principal Geotechnical Engineer
(602) 437 3737