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Technical Paper

What successful Cost Estimators know. . . . and you should, too.





submitted by Gary Terrell CPE, LEEDAP

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
received first rate training and found
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
employees skills and talents. He has
9) Sample Sketches
a BA in Music from Vassar College in
Poughkeepsie, NY.



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.



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


October 2009

corridor, which need to be fire-rated and may

or may not require locking hardware.


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 its 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 its 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


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 doesnt, but there isnt 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.


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



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 youre pricing. This will
in turn allow their door assembly knowledge
and experience to bolster your own.


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
its for an owner or in-house review, and
having data to justify the assumptions youve
made will, in the least, foster conversations
to further develop your assumptions, and will
bolster everyones confidence in the estimate,
including your own.


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.


Rather than direct you to information that may

be for suppliers or manufacturers that dont
operate in your area, I would recommend a
search for doors and hardware that are in use in
your area. Most hardware has the manufacturers name stamped near the latch and fire-rated
doors must have a label, typically with the
manufacturers 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


October 2009

Estimating Today

Drawings reproduced with the permission

of the HMMA Division of NAAMM,
National Association of Architectural Metal
Manufactures - Glen Ellyn, IL.