Technical Paper What successful Cost Estimators know. . . . and you should, too. >>>>>>> AN ESTIMATOR’S GUIDE TO POLICIES, >>>>>>>>>>> PROCEDURES, AND STRATEGIES ESTIMATE THE COST OF DOORS, FRAMES, AND HARD WARE F O R A C O N C E P T UA L E S T I M AT E submitted by Gary Terrell CPE, LEED®AP Gary Terrell CPE has been involved in construction for approximately 25 years starting with residential painting and roofing during his college summers. He switched to high end residential construction management after college, and changed to 1) Introduction commercial construction after moving 2) Types and Methods of Measurement to San Francisco. In San Francisco 3) Specific Factors to Consider his career as a Commercial Construc • Frames tion Estimator began and took root; he • Doors received first rate training and found • Hardware the variety and complexity of his proj • LEED ects intellectually stimulating. After returning to the East Coast he was for- 4) Overview 5) Risk Considerations tunate enough to work for a company 6) Ratios and Analysis with equally rewarding projects and a 7) Miscellaneous Information dedication to the advancement of their 8) Sample Take Off and Pricing employee’s skills and talents. He has 9) Sample Sketches a BA in Music from Vassar College in Poughkeepsie, NY. www.aspenational.org 9 ESTIMATE THE COST OF DOORS, FRAMES, AND HARDWARE A C O N C E P T UA L E S T I M AT E Introduction Doors, Frames, and Hardware are integral parts of virtually every building project and need to be accounted for through all phases of design development to accurately reflect the complete cost of construction. This paper illustrates how to estimate the cost of doors for a conceptual estimate. a) Main CSI Division: Division 8 – Doors and Windows b) Specific Sub-Divisions: 08100 – Metal Doors and Frames 08200 – Wood and Plastic Doors 08700 – Hardware c) The subject of this paper is how to estimate the cost of Doors, Frames, and Hardware for a Conceptual Estimate. In order to limit the length of this paper it is based on swinging door assemblies as opposed to sliding door assemblies and will focus on door assemblies typically installed in general office and institutional projects; however, the methods of quantification and many of the specific considerations can be applied to a wider variety of construction projects and door assemblies. TYPES AND METHODS OF MEASUREMENT In conceptual estimates, doors, frames, and hardware are quantified by count of assembly types. A partial list of assembly types would include: single un-rated door assemblies; single rated doors assemblies; double un-rated door assemblies; double rated door assemblies; rated egress doors; single un-rated doors with sidelights; and perimeter (or exterior) door assemblies. Rated door assemblies are resistant to fire and offer varying levels of protection against fire depending on the properties of the components of the door assembly and assuming proper installation of the door assembly. Documents available for a conceptual estimate will almost certainly neither include a door schedule nor a hardware schedule, so assumptions will need to be made about the characteristics of the various door assemblies based on location or function. When quantifying it is best to start with door assemblies that are known to have a specific function. Door assemblies to an egress stair are a prime example; these doors will need to be fire-rated and will likely require panic hardware which also needs to be firerated. Other door assemblies with attributes governed by their function include those for electrical rooms or closets, which need to be fire-rated and typically require locking hardware, as well as those along an egress 10 October 2009 corridor, which need to be fire-rated and may or may not require locking hardware. SPECIFIC FACTORS TO CONSDIER: There are many factors that affect the pricing of doors, frames and hardware for a conceptual estimate; however, the three major components of the door assembly (frames, doors, and finish hardware) have the greatest impact upon pricing of the door assemblies and each will be addressed separately. Other cost factors, with less emphatic impact, will also be addressed. a) FRAMES: Door frames are the part of the door assembly that engages the partition or wall, trims the opening, provides anchoring points for the hinges, and, frequently, stops that keep the door from swinging back through the opening. In estimating frame pricing for a conceptual estimate there a number of factors that need to be considered, some of which have collateral cost implications. i) Frame type: Two common metal door frame types are welded metal frames and knock down (frequently referred to as KD) frames. There are advantages and disadvantages to each type of frame. KD frames allow greater ordering flexibility by having some adjustability of throat size and because KD frames can be installed later in the construction schedule, which allows for the accommodation of late design changes; however, many owners and designers feel KD frames are inferior to welded frames. Welded frames need to be installed during partition construction and are inherently stiffer and stronger than KD frames. Welded frames also allow for integrated sidelights, transoms, or both constructed with the same frame profile so the frame of the borrowed lights match those of the door frame. ii) Frame size and side lites: Frame sizes between 2’-6” by 6’-8” and 3’-6” by 8’-0” are quite common and do not vary greatly in cost. Frames that do not fit within those dimensions need to be custom manufactured, which increases costs dramatically. Likewise, there are off-the-shelf frames with commonly sized sidelights that have virtually the same cost as door frames without sidelights. When large sidelights, or transoms, or large sidelights with transoms are added, costs increase rapidly; these larger, more expensive frames also have a profound impact on the installation labor required. Imagine transporting, erecting, and securing a large, rigid frame in a contained area; it requires more work- ers, more planning, and a more deliberate, careful, coordinated and time consuming handling and installation operation. iii)Throat sizes: The most typical, and therefore most commonly and efficiently produced, and least costly door frames are manufactured with throat sizes made to fit around a typical partition such as 4-7/8” (3-5/8” stud with one layer of 5/8” gypsum wall board on each side). Frames with throats to accommodate other common partition dimensions are also readily available and remain competitively priced. But, when large or unusual, or both large and unusual partition dimensions need to be accommodated, the additional cost to produce these custom frames can rise very steeply, as will the cost of the labor required to install them. iv)Installation: Installation of KD frames is a quicker process than installing welded frames; however, all frames need to be installed plum and square requiring at least three checks with a leveling device and, more realistically, numerous checks and at least an equal number of adjustments and placing of shims to keep the frame plum and square as it is secured. Installation of welded frames needs to be completed during the construction of the partition assembly regardless of whether the partition is gypsum, concrete or CMU. As previously mentioned, large frames, especially frames with large sidelights, transoms, or both, are more difficult and costly to handle and install, requiring a larger crew and more room to maneuver. b) DOORS: Doors are the largest piece of the door assembly; they close the opening, but have no moving parts. Types of doors, sometimes referred to as slabs or leaves, discussed in this paper include hollow metal and solid core wood doors. This paper does not address style and rail doors, which are commonly a finish carpentry item. i) Sizes: The most common door size for a commercial project is 3’-0” wide by 7’-0” width by height. Doors from 2’-6” through 3’-6” wide increasing by 2” increments, and from 6’-8” high to 8’-0” high also increasing by set increments, are fairly standard and do not vary greatly in cost. Once door dimensions go beyond those parameters, regardless of whether it’s larger or smaller, their prices increase rapidly. ii) Un-rated Doors: Un-rated doors are common and the least expensive doors available. Some un-rated doors, but not the hardware, are manufactured using the Estimating Today same materials and process as rated doors; however, without the affixed label that certifies the door is fire rated, it cannot be used in an opening that requires a rated door. iii)Fire rated Doors: Hollow metal doors without a fire rating are typically more expensive than pre-finished wood doors; however, when a fire rating greater than 20 minutes for the opening is required, hollow metal doors become the less expensive option because wood doors require a fire resistive core to achieve the fire rating. iv)Sound Rated Doors (STC – Sound Transmission Class): The cost of door assemblies that satisfy STC ratings varies greatly depending on the level of sound attenuation required. Higher STC rating values transmit less sound, and the scale is exponential so seemly minor rating increases can have substantial cost impact. v) Preparation for Hardware: Door slabs can, and should, whenever possible, be ordered so they are prepared to receive the hardware that will be installed upon or within them. For a majority of doors this is accomplished by having recesses to accommodate the hinges; blocking within the door for the hinge screws to fasten to; and holes cored or mortise pocket for the operating hardware (door knob or lever). Hardware preparation for rated doors, however, whether for fire or STC, is more involved and must be taken into consideration when estimating door assembly unit rates. Rated door assemblies have, in addition to the hardware listed above, closers and smoke gaskets; and may have a number of other hardware components. STC rated doors start with a similar compliment, but may also require a gasket at the bottom of the door which seals against the threshold to help minimize sound transmission. The door needs to be prepared to accept all hardware and it’s best if the supplier is responsible for the preparation; however, regardless of who prepares the door, the preparation needs to be considered when estimating the cost of the doors. c) HARDWARE: Hardware includes all the moving parts, such as hinges and latching mechanisms; trim, kick plates, strike plates, and gaskets, which collectively help the door assembly meet the requirements of the opening when closed, but allow the door to easily be opened. Hardware also helps give the door assembly a finished appearance. Of the major components of a door assembly, the hardware has the widest range of cost both for the material and for labor required for installation. i) Types: Hardware for a door assembly can vary from items as small and simple as two pair of hinges and a pull for a closet door; to hinges and a privacy function mechanism for a single occupant toilet room; to hinges, closer, panic hardware, and smoke gaskets for an egress door; to hinges, closer, kick plate, weather stripping and sound gaskets, including one that drops down to the threshold when the door is closed for a STC door assembly. An estimator should assume, unless specifically instructed otherwise, that all door assemblies will have at a minimum three pairs of hinges and a core latching mechanism with a passage function. As a door assembly hardware package gets more complex - from a passage function to a privacy function, to a privacy function with an occupancy indicator, to a function to drop a gasket, to panic hardware - the hardware package gains moving parts, becoming more involved to install, and requiring more adjustment during installation. Note that typical hinges come in pairs with one leaf of the pair attached to the door, the other attached to the frame and the pair connected to one another by a pin. ii) Type Complexity: The various types of hardware, various components in a door assembly hardware package, and the complexity of the hardware can all have a substantial impact on the overall cost of the door assembly; before even considering the quality and finish of the hardware. Certainly the number of components in a door assembly hardware package has cost impact, but the complexity of the hardware package typically has a more profound impact both on the cost to furnish and on the cost to install. iii)Hardware Quality: Just like nearly all other consumer goods, door hardware comes in varying degrees of quality and in an array of finish options. Most commercial clients and designers seem content to keep up with the Joneses and therefore projects of similar function and level of finish will likely have similar hardware. This is a fair and defendable assumption provided no instructions to the contrary have been issued. The case for this argument and any other conceptual estimate assumptions is best made proactively before other expectations have been formulated. d) QUANTITY: Door assemblies do not vary greatly in cost due to quantity unless those quantities are very small. In fact, the quantity needs to be so small that minimum labor charges, typically four hours, would need to be spread over a small quantity of door assemblies to have an appreciable cost impact. If there are three or more doors on the project being estimated that can all be installed during one mobilization, then the cost per unit for similar door assemblies should not vary greatly. Large quantities of doors can also reduce the cost of the door assemblies; however, the quantities must be fairly large: at least one hundred, with a high percentage of repetition for the cost reduction to have much of an impact on the rate per unit. e) LEED: Leadership in Energy and Environmental Design may have some impact on door assembly costs, but, at this time, the cost impact is minor and only affects a couple aspects of door assembly costs. Doors can be potentially applied toward LEED credits in two ways. The first is if they are manufactured within 500 miles of the project site. Typically the distance between the project and door manufacturer either meets this criteria or it doesn’t, but there isn’t usually a cost impact. There may be a cost increase if the project absolutely needs the door credit to achieve the desired LEED level of certification, and if a less competitively priced but more closely located door manufacturer must be used. The second way LEED can impact the doors on the project is when wood doors are specified to have no added urea-formaldehyde during manufacturing. This, however, affects the lead-time for the doors, not the cost. LEED by its very nature is changing rapidly and will continue to do so; therefore, LEED considerations affecting the cost of door assemblies may change and should be confirmed prior to issuing an estimate. OVERVIEW: Labor for door assembly installation is fairly level for a typical door frame, with the greatest factor being the physical size and weight of the frame itself. The labor involved for the installation of a typical door is more consistent, as doors tend to be manageable in size and weight and have limited moving parts and attachment points; this all assumes a properly squared, plumbed and leveled frame. The labor required to install hardware packages, on the other hand, can vary greatly with the complexity and sheer number of components and moving parts of the hardware package. The increased labor cost combined with the increased material cost for a complex hardware package can make the overall cost increase for differing types of door assemblies appear exponential. In fact, when they are broken down and reviewed they can be explained and, if need be, justified with conviction. The best source for labor production rates is historical data gleaned from past projects. If that data is not available, visualizing how the frame and hardware will www.aspenational.org 11 ESTIMATE THE COST OF DOORS, FRAMES, AND HARDWARE be installed, and imagining how each of the various pieces of hardware (including all the sundry fasteners) is your next best approach. Finally, you can consult RS Means for a point of reference. Material pricing for doors, frames, and hardware can usually be obtained quickly through a phone call, fax, or email to a supplier. Start with a call, as the supplier will almost certainly ask you questions that will help you think with greater depth about the door assemblies you’re pricing. This will in turn allow their door assembly knowledge and experience to bolster your own. RISK CONSIDERATIONS: Preparing a conceptual estimate requires making numerous assumptions. When it comes to the door assemblies, the estimator needs to make assumptions about the three major components that constitute the door assemblies. If the estimate is for an addition or renovation, use the door assemblies already in place to guide your assumptions. If the estimate is for new construction, visit a comparable facility to guide your assumptions. Whatever assumptions you make, relaying those assumptions clearly to your audience, whether it’s for an owner or in-house review, and having data to justify the assumptions you’ve made will, in the least, foster conversations to further develop your assumptions, and will bolster everyone’s confidence in the estimate, including your own. RATIOS AND ANALYSIS: Because of the great variety of door assemblies and the varying degree to which they are used from one project to the next, there are no reliable ratios that can be used as a back check. If you have been working on very similar projects - for instance a number of similar hospitals, or a string of similar office buildings, or similar apartment buildings then comparing the ratios from completed projects against the similar project you are currently working on can be a beneficial back check. Also, the overall cost of similar door assemblies can be utilized as a useful comparison for your current estimate. MISCELLANEOUS INFORMATION: Rather than direct you to information that may be for suppliers or manufacturers that don’t operate in your area, I would recommend a search for doors and hardware that are in use in your area. Most hardware has the manufacturer’s name stamped near the latch and fire-rated doors must have a label, typically with the manufacturer’s name affixed to the door along the rail where the hinges attach. Searching the internet for the manufacturer in conjunction with “door” or “door hardware” will give you ample results and lead you to plenty of information. A resource for general information is the HMMA portion of the NAAMM website at http://www.naamm.org/hmma/. 12 October 2009 Estimating Today Drawings reproduced with the permission of the HMMA Division of NAAMM, National Association of Architectural Metal Manufactures - Glen Ellyn, IL. www.aspenational.org 13
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