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By: Michael G. E. Mount, AIA  
Issue: February/March 2006

Most cities and towns have experienced periods of time where buildings in their communities, for whatever reason, have become abandoned, later to be either remodeled for a different use or demolished to make room for something new. There appears to be a general opinion among many public building planners and decision makers that there will invariably be some inherent construction cost savings in the remodeling of an existing building, simply because it is existing. Depending on a number of variables that will be explored below, this may be true in some cases, maybe even in most cases. But time and again it has been proven that in some specific instances it can be more expensive to remodel an existing building than to construct a new building for the same use.

Remodeling an Existing Building
Remodeling an existing building is generally economical if the building is in relatively good condition and the proposed use for the building requires relatively simple, straight-forward building systems. However, if the proposed use for the existing building is for a forensic laboratory, it must be understood that the building systems to be included in this remodel project are of a highly technical, specialized, and complex nature. This will necessitate a thorough examination of the existing building in order to assess its suitability to be remodeled into a crime lab.

In some cases it might be financially prohibitive to remodel an existing building regardless of the complexity of its intended use. The fact that the building has at least a foundation, exterior walls, and a roof might not be enough to render it a feasible candidate for remodeling. An initial assessment of an existing building should include determining the age of the building and obtaining construction drawings and specifications of the building, if they are available. Here are some of the items that should be examined and assessed.

Condition of Existing Utilities. Existing utilities include mechanical, plumbing, electrical, and telecommunications equipment and their respective distribution systems. The condition and capacity of existing boilers, chillers, air handlers, duct work, plumbing fixtures, piping, transformers, generators, power panels, and wiring are a few of the items that should be examined to determine if they have any remaining useable life or if they should be replaced, and what costs might be involved.

Building Code Compliance. Most regulating agencies require that the design for the remodel of an existing building shall include all necessary upgrades required to render the building in complete compliance with current building codes. Since building codes are constantly being revised to include more stringent requirements, this could result in some significant additional construction costs, depending on the age of the building and the extent of the upgrades required for building code compliance. The assessment of any building being considered for a remodel should include a complete building code analysis.

Asbestos. The U.S. Environmental Protection Agency has identified forty-six building materials that may contain asbestos (www.epa.gov/Region6/6pd/ asbestos/asbmatl.htm). Although the use of asbestos containing materials is currently illegal in most jurisdictions, they were used without restrictions in building construction as recently as the 1980s. If asbestos is determined to be present, most building authorities would require the total abatement of the asbestos which, depending on the age of the building and the extent of the asbestos materials, can be another very costly effort.

Structural Condition. Directly related to building code compliance is an assessment of the structure of the building. This issue can be particularly critical in earthquake and hurricane zones, where local building codes are frequently upgraded to include more stringent requirements for the structural resistance to these natural forces.
Infestations. Is the building considered old? Does it have a history of water infiltration, either through roof leaks or at window and door openings? Is the basic structure wood? If the answer to any of these questions is yes, the building should be examined for mold and termites. Mitigation of these types of infestations can be costly.

Roof Condition. Although the structural integrity of the roof may be sound, it is critical to assess the weather-tight integrity of the finished roofing system and materials, including its age, repair history, and its replacement cost. Any needed, expensive roofing replacement or repair costs should be addressed as part of the project’s development costs.

Interstitial Space. The space within a building between the ceiling and the structure for the floor or roof above is called the interstitial space. An adequate amount of interstitial space is essential for the successful, efficient, and economical design of a forensic laboratory, yet this is probably the most overlooked item when assessing an existing building. The interstitial space for a forensic laboratory will include distribution systems for HVAC ductwork, fire sprinkler lines, domestic and treated laboratory water lines, power and data lines, light fixtures, plumbing drains, and waste lines. It will include exhaust ductwork for fume hoods, instrumentation equipment, drying rooms, cyanoacrylate cabinets, bullet recovery tanks, and firing range supply and exhaust. Figure 1 (on page 20) shows the interstitial space in the corridor of the Sacramento County Forensic Laboratory. In this particular design a ceiling was not provided in the corridor in order to provide ready access for maintenance, but also to show the myriad of utility distribution systems located in the building’s interstitial space. An optimum vertical dimension for the interstitial space in a crime lab is 4 feet. Assuming a floor-to-ceiling height of 9 feet and 3 feet for the floor or roof structure above, an ideal floor-to-floor (or floor-to-roof) dimension is 16 feet.

Feasibility Evaluation
Evaluating the financial feasibility of remodeling an existing building into a forensic laboratory involves applying two simple cost formulas. Application of these cost formulas is the simple part, but determining the value of the applicable variables in each formula will involve a careful and thorough building evaluation and construction cost exercise. Variables for the formulas are:
N = Construction cost for building a totally new forensic laboratory in lieu of remodeling an existing building. This is the control variable.

D = Cost of demolition, removal, and disposal of items in the existing building that have no more useful life. This variable also includes asbestos abatement.

S = Current value of all systems and materials that have useful life and can remain as part of the existing building, i.e., the cost associated with these items if they were to be constructed new.

A = New construction cost for all systems and materials that must be added to the building, which theoretically should equal N - S.

T = Total construction cost for remodeling the existing building into a forensic laboratory.

The two simple formulas are:
T = N - S + D
T = D + A

In order for the remodel project to be financially feasible, T must be less than N.

The estimated cost for construction of a new forensic laboratory building, variable “N,” can be determined by evaluating historical construction cost data from recently constructed crime labs. According to the data maintained by SmithGroup, on a national average a crime laboratory can be constructed for approximately $280 per square foot. This figure will vary depending on the size of the laboratory, geographical location, and other variables that can be assessed by an architect who is familiar with forensic laboratory design.

Variables “D,” “S,” and “A” can be determined through line-item cost estimating using cost estimating guides and formats such as those provided by the Construction Specifications Institute (CSI) or R.S. Means Company. Again, an architect with experience in the design of forensic laboratories can determine these costs figures as part of the existing building assessment.

Let us examine two possible scenarios where an existing building is being considered as a remodel project for a new crime lab.

Scenario 1
Let us assume that a comprehensive needs assessment has determined that the new crime lab needs 41,500 square feet of floor space. An abandoned, fifteen year old, 40,000 square foot warehouse is being considered, and it is determined that design efficiencies can be incorporated to absorb the 1,500 square foot deficit. A thorough building analysis has revealed that the building’s structure meets current building codes, it contains no asbestos, and its entire roof was replaced less than five years ago. Ninety percent of the floor area is open warehouse space with a clear inside height to the bottom of the roof structure of 14 feet. The remaining ten percent of the building consists of office spaces. The minimal amount of demolition required is limited to some interior partitions and doors and some saw-cuts in the floor slab for laboratory drains. As a warehouse facility the mechanical, plumbing, and electrical infrastructure are minimal, but it is determined that the existing HVAC systems can be used to partially satisfy the HVAC needs for the crime lab’s administrative office spaces.

After conducting a thorough cost analysis, the following was revealed:

(1) Demolition will amount to $175,000 (variable “D”).

(2) The existing building systems and components that have useful life include the foundation, floor slab, exterior walls and insulation, roof structure and roofing, HVAC system, and minimal amounts of plumbing and electrical infrastructure. The value of these systems and components, i.e., what it would cost to construct them today, is determined to be approximately $2,150,000 (variable “S”).

(3) The building and laboratory systems and components that will have to be added into this building are extensive. Some of the more significant items are interior partitions, doors, ceilings and finishes; laboratory casework, fume hoods, and equipment; upgraded mechanical, plumbing, electrical, and telecommunications infrastructure and distribution systems. The estimated cost for these items is approximately $9,050,000 (variable “A”).

(4) At $280 per square foot, a new 40,000 square foot building, finished and equipped as a forensic laboratory, will cost $11,200,000 (control variable “N”).

Now let us apply the formula, T = N - S + D, where N = new construction, S = value of useful existing systems and components, and D = demolition costs.

T = $11,200,000 - $2,150,000 + $175,000
T = $9,225,000 = estimated remodel construction cost.

Testing the above results with the second formula, T = D + A, where D = demolition cost and A = cost of new systems and materials to be added.

T = $175,000 + $9,050,000
T = $9,225,000 = estimated remodel construction cost. “T” being less that “N” shows a savings in construction cost in this scenario of $1,975,000 less than the cost for new construction.

Figure 1: Sacramento County Crime Laboratory main corridor showing the extensive utility systems located in the interstitial space.

Scenario 2
This scenario has a totally different set of parameters. We will assume that the 41,500 square feet space need for the crime lab as described in Scenario 1 still applies. The existing building being considered is a two-story office building, twenty-five years old, with 22,000 square feet per floor, slightly larger than needed, but close enough that the excess space will be put to good use. The structure of the building is pre-cast concrete, and despite its age it is structurally sound and complies with current building codes. Clear vertical space from the floor to the structure above on both floors is 10 feet. A new roof was installed less than five years ago.

It appears that demolition costs will be extensive. Most of the interior of the building will have to be gutted. The existing office partitions and doors are showing the effects of age and are not in a floor plan configuration that is conducive to an efficient forensic laboratory layout. Interior finishes, including carpet, tile, and ceilings are worn and must be removed. The building does contain asbestos in pipe insulation and flooring material. There is also evidence of mold in some of the partitions, the extent of which will not be determined until demolition occurs. The HVAC systems include the original equipment and ductwork, which has been repaired extensively over the years, all of which has outlived its useful life.

On the positive side, the building has a good foundation and building enclosure, including floors, walls and roof structure, and a weather-tight roof. It also has an elevator that is in good operating condition.

The cost analysis for this building reveals the following information:

(1) Demolition will include the removal all interior partitions, doors, ceilings and finishes; abatement of asbestos and mold; removal of all mechanical and plumbing equipment and their respective distribution systems; and saw cutting in the floor slab for laboratory drains. Estimated cost for demolition is $2,250,000 (variable “D”).

(2) The existing building systems and components that have useful life include the foundation, floor slab, second floor structure, exterior walls and insulation, roof structure and roofing, and minimal amounts of the electrical infrastructure. The value of these systems and components is determined to be approximately $2,050,000 (variable “S”).

(3) Like Scenario 1, the building and laboratory systems and components that will have to be added into this building are extensive. Some of the more significant items are interior partitions, doors, ceilings and finishes; laboratory casework, fume hoods, and equipment; new mechanical, plumbing, electrical, and telecommunications infrastructure and distribution systems. The estimated cost for these items is approximately $10,270,000 (variable “A”).

(4) At $280 per square foot, a new 44,000 square foot building, finished and equipped as a forensic laboratory, will cost $12,320,000 (control variable “N”).

(5) An additional construction cost increase that is not applicable to the building in Scenario 1 will have to be added to the cost for this building. This cost premium is the result of the low floor-to-structure height of 10 feet. Although the minimum standard ceiling height for a forensic laboratory space is 9 feet, it can go as low as 8.5 feet, which is the recommended minimum for adequate installation and connections of fume hood exhaust ducts. This would result in an interstitial space of less than 1.5 feet, and would necessitate some very awkward and undesirable designs for utility distributions. An example would be the need to provide soffits above wall casework in order to run ductwork and other utilities horizontally below the ceiling height. Lengthy utility runs might be needed where inadequate interstitial space will not allow utilities to cross over each other. Installation of some utilities between structural members or through the web components of beams and joists might be required. These and other undesirable design features resulting from inadequate interstitial space will increase, not only the construction costs, but also the architectural and engineering design fees. We will call this new variable “P” and the additional premium cost that might be expected in this building is $650,000.

Now let us apply the new formula, T = N - S + D + P, where N = new construction, S = value of useful systems and components, D = demolition costs, and P = the premium paid for inadequate interstitial space.

T = $12,320,000 - $2,050,000 + $2,250,000 + $650,000
T = $13,170,000 = estimated remodel construction cost.

Testing the above results with the second formula and adding the P variable, T = D + A + P, where D = demolition cost,
A = cost of systems and materials to be added, and P = the premium paid for inadequate interstitial space.
T = $2,250,000 + $10,270,000 + $650,000
T = $13,170,000 = estimated remodel construction cost. “T” being greater than “N” shows that the construction cost for remodeling the building in this scenario would cost $850,000 more than new construction.

One additional check that can be made is to compare variables “D” and “S.” If D is greater than S, the remodel project will not be financially feasible. If “D” is less than “S” the project will be feasible. This is a shortcut check that should not preclude a thorough examination of all cost variables in order to be assured of the feasibility of the project.

Conclusion
The above two scenarios both represent potential reality. In searching for an existing building to be remodeled into a forensic laboratory, some, most, or even all of the conditions described above might be encountered.

Michael Mount has devoted the past 20 years of his career as an architect almost exclusively to the planning and design of forensic laboratories. He is currently a principal with SmithGroup. The combined experience within SmithGroup's nine offices includes the planning and design of over 6-million square feet of forensic facilities throughout the United States and abroad. Michael can be reached at Michael.mount@smithgroup.com