I am frequently amazed at how difficult it is to convince the prospective owners of a new laboratory building, not necessarily the scientists who will use the building, that they know more about what their needs are than anyone else. Owners often do not realize that they can determine their needs by examining an existing facility-even if it is someone s. Once owners have projected their future needs in programs and people, it is easy to project the need for space.
Determining Space Needs
Although area (expressed in square feet in the United States and in square meters in most other parts of the world) is the accepted form of space projection, it is not necessarily the best means of determining real needs.
Some 25 years ago, I began looking at another factor that I think is the real driver in determining space needs-the ELF, or equivalent lineal feet of bench necessary to support a person in a particular activity. This factor is determined by measuring the lineal footage of anything that occupies floor space in the laboratory. If it is a piece of apparatus requiring front and back access, for example, all sides of the apparatus are included in the measurement. We have found that it is much easier to determine whether this factor is adequate than it is to determine whether square footage is adequate.
Let's assume that an existing bench lab is 30 feet by 9 feet, or 270 square feet, with 60 ELF. If that 60 linear feet is made up of benches 30 feet long by 33 inches deep on either side of the lab, the working aisle width is 3 feet 6 inches, which is totally inadequate for two people to work in safely. To cure this deficiency we can increase the width of the lab to 10 feet, giving us a 4-foot-6-inch aisle. We have now increased the projected space need to 300 square feet and still have only
You can estimate how wide a lab space you will need by determining the ELF needs of each person using the lab and allowing for an adequate working aisle; allow half the total ELF for the depth.
The Planning Module
Such determinations yield what is referred to as the planning module. It is not uncommon to have more than one planning module. And certainly compromise is required in order to arrive at the module depth, since related activities will have a range of ELF requirements.
Some common module widths in the physical and biological sciences today are 10 feet 6 inches and 11 feet. If you are going to employ larger open spaces (commonly referred to as open planning), 10-foot modules are generally acceptable. The width dimension in these examples is calculated from the center line to the center line of potential walls, not from the inside of one wall to the inside of the other.
Square Footage Designations
It is important to distinguish between some square footage designations that you are apt to come across. These are:
- Net assignable square feet (NASF), the actual inside room dimensions. This designation is frequently used by academic institutions to establish space budgets and billings, although in a modular space building it is useless because it changes with every addition or deletion of a wall without having any overall effect on the space designated.
- Net square feet (NSF), the amount of space set forth for a specific program need, such as laboratories, exclusive of public or building support spaces, such as corridors and mechanical rooms. This designation is sometimes the same as net assignable square feet, but because it ignores nominal thicknesses of dividing walls it becomes a constant modular value once it is established.
- Gross square feet (GSF), the total amount of space in a structure, including all programmed and non-programmed spaces.
- Rentable square feet (RSF), the non-owner occupied space, which may include a part of corridors, toilets and lobbies.
The efficiency of a building is generally considered to be the ratio of the net to the gross of the building areas and, again generally, will run from 50 to 65 percent for multi-story laboratory buildings.
In the early '60s I was part of the design team for the Salk Institute for Biological Studies at La Jolla, California, which introduced what has come to be known as the interstitial space building. In such a building each programmed, or usable, floor is overlaid with essentially another floor that houses all the mechanical and electrical systems for the programmed floor as well as ancillary lab equipment. It is difficult to evaluate the efficiency of this type of building, for if the non-programmed areas are considered in calculating the efficiency it is very low and if they are not considered it is very high.
Many projects have been led astray or totally lost because owners did not understand cost figures. It is wise when gathering cost data to verify exactly what is included.
Construction cost is generally, although not universally, considered to be the amount charged by a contractor to construct the building. Frequently this cost will include site development costs such as roads, parking lots and landscaping; sometimes it will include the cost of a construction manager. The cost of the building itself is normally considered to include all work to a point 5 feet beyond the foundation walls.
Project cost is generally considered to be the total cost of the project. As a rule, the project cost will be from 15 to 35 percent more than the construction cost. It may include the cost of site acquisition, architects' and engineers' fees, permits, moving, loose equipment and furnishings, surge space rental, and down time losses.
In addition to construction cost and project cost, cost is customarily expressed as cost per gross square foot-construction or project cost divided by the gross square feet.
Even if you understand exactly what cost is being set forth, if you are using the cost of another building to project what your lab is apt to cost, you need to know as much as you can about that building. You need to know not only the gross but the net square footage and, preferably, to have a breakdown of the net space.
Consider, for instance, a lab that contains 100,000 gross square feet constructed at a cost of $100 a gross square foot. A close look may show that the building is 60 per cent efficient, or has 60,000 net square feet. But an even closer look may show that, although it is called a lab building, labs account for only 20,000 net square feet. If you use the $100 per gross square foot figure to calculate the projected cost of a building of similar size in which labs account for 40,000 net square feet, you will arrive at a misleading figure. You have to compare apples and apples. But how? I wish I could say it is easy, but, without some level of architectural detail, predicting costs is most difficult indeed.
A Method for Estimating Cost
All is not totally lost, however. I have a relatively simple method that will at least get you into the ball park. But do remember that it is a big ball park.
If you can get the gross square footage and net lab area of a building at least somewhat similar to what you are contemplating, as well as the dollars per gross square foot cost for the building, you have a basis for comparison.
Take the net square footage projected for the new building and, de pending on how conservative you are, assume an efficiency of 55 to 60 percent to arrive at a figure for gross square feet. You can then use this figure to determine the percentage of the gross that is net lab space and compare the percentage to the corresponding figure for the comparison building.
The trick is to judge how much more the lab space in the comparison building has cost than the non-lab space. Here you may need some help from a professional estimator.
As an example, assume that your cost comparison base is a building of 100,000 gross square feet that cost $100 a gross square foot, or $10,000,000, and that 20 percent of the gross is net lab space. For lack of a better number, assume that lab space costs 40 percent more than non-lab space (this will vary considerably depending on the type of lab). Therefore for the comparison lab:
.8x 100,000 x X + .2 x 100,000 x 1.4X = $10,000,000
80,000X + 28,000X = $10,000,000
x = $92.59.
If you are considering building a lab of 100,000 gross square feet in which 40 percent ofthe gross is net lab space, then:
.6 x 100,000 x $92.59 + .4 x 100,000 x 1.4($92.59) = X
5,555,400 + 5,185,040 = $10,740,440.
The proposed lab would thus cost $107.40 per gross square foot, or 7.4 percent more than the comparison lab. And you must allow for inflation, too.
This method is crude, but it's one way of arriving at an estimated cost.
Earl L. Walls is a laboratory programming and design consultant.