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OCR for page 95
P A R T
PRESIDING CI-IAIRMAN
W. E. Reynolds
Consulting Engineer, N\~ashington, D. C.
r 0 u R
CosIs and
Maintenance
MR. SILLING: In tile past, whenever ~ met your next session chairn~an,
he did the presiding and ~ was listening, and very carefully. You see, he
was in a position to snake one rich. TIe was the Fecleral Con~issioner of
Public BuilcTings and hired architects by tile hundrecI. They had to certify
their record on a government form in a cJefinite, prescribed manner. There
was no place to show those beautiful red, white and blue pipe drunks that
architects are very fond of drawing to mislead their clients, and he wouIcl
not listen to any fancy talk. A 1larcl ~nan--but fair. And with a sharp
knowlecige of how to use an architect eRectively, and also Low much or
LOW little to pay hint.
Even uncler other personnel, tile clepart~nent that Ile Ileaclec! up still
persists in that manner.
He was educatec] as an engineer. However, architects have long since
forgiven hint for this oversight. TVe are proud to count hint an honorary
November of the American Institute of Architects and publicly declare our
sincere af ection for fling. Gentlemen, Mr. TV. E. Reynolds, Consulting
Engineer of Washington, D. C.
95
OCR for page 96
OCR for page 97
. ~
. I:
. ~
In-The-Wall Costs
MR. REYNOLDS: ~ think that this particular
session is one of the more important ones that
you have at this meeting. It is very often over-
Zooked by many people in the construction
industry that maintenance is a very vital factor
in the design of ~ structure. We have proved
in various ways that it is sometimes profitable
to pay more in first construction in order to
eliminate maintenance, which is a continuing
problem throughout the life of a betiding.
Tt is now my pleasure to introduce Mr. H. T.
· . ~
H. Ta Nones
Turner Construction Company,
New York, N. Y.
Noyes, Assistant Chief Engineer of Turner
Construction Company since 1926. He was
chief buiZ3ing engineer and later chief engi-
neer of the joint venture titled "Contractor,
Pacific Naval Air Bases" at Pearl Harbor from
October 1939 through July 1945.
He attended the School of Technology of
the City College of New York and has ~ Bach-
eZor of Science degree and a Civil Engineering
degree. He is a member of the American
Society of Civil Engineers.
MANY great advances have been made in out of all comparison with general living costs.
buildings since the end of World War 1:~. While the walls of buildings have increased
These advances in design have greatly in- in cost in step with other items. their crocor-
creased the usefulness of buildings and certain-
ly the comfort and efficiency of their occu-
pants. But they have increased building costs
--- r--r--
tion of the total building cost has generally
gone downward. This is particularly true of
masonry-waIled buildings, as is well illustrated
97
OCR for page 98
by a comparison between a 20-story office
building built in 1977 and a sin~ilar 25-story
buiTcTing built in 1949-50. The brick and stone
walls, including the windows, glass, etc.,
an~ountec! to 19.~:O of the total cost of the
192/ building. The similar walls of the 1949-
50 building an~ountecT to only S.29~/o. The rea-
son for this, of course, is the very great in-
crease in the cost of mechanical work in the
average building due to the adclition of air
conditioning and to a very great increase in the
complexity of the electrical system in the
newer buiTcling. The cost ratio of the con~-
binecI electrical ancl mechanical items in the
builclings ~nentionecl above increased front
77.527~ in tee case of the 1977 buiTcling to
44-547 in the 1949-50 building.
Tile opinions of the great mass of people
who fool; at, visit, ancT occupy buiTclings are
greatly influenced by outward appearances.
Because of this, the walls have retained and
shouicT retain very great importance in the de-
velop~nent of any building clesign. Architects
in endeavoring to obtain new and modern ap-
pearances are designing walls using masonry in
its various forms, combinations of masonry;
with metal and glass, and combinations of
natal, glass and/or other materials without
the use of n~asonr~;.
While this conference is primarily intenclecT
as a discussion of masonry, no such discussions
have any meaning without a comparison of the
cost of masonry walls with other types.
The preparation of comparisons of costs of
walls is not easy, as any such comparison nudist
recognize that the costs divicle themselves into
two basic categories:
1. Direct Costs including flee cost of:
a. Masonry
b. Metal Savory
c. Spandrels
d. Windows
e. Dampproofing and Insulation
f. Scaffolding
as
i,. Air Conditioning Unit Enclosures
1~. Little and Plaster
i. Sun Control Installation. such as Venetian
Blinds
i. Other similar items
a. Indirect Costs
. Effect upon Structural Uranic and lTounda-
tions
b. Efl ect upon I-Icating and Air Conclitioning
So stems
c. Effect upon Lighting System
d. Effect upon Speed of Erection
e. Effect upon Rentable Arca
f. Eficct upon Window N\:asl~in<, Equipmcut
g. Effect upon Sound Transmission
1~. Effect upon Gcncral Comfort of Occupants
i. Effect upon Maintenance
i. Influcncccl by Code Rcquircments
1;. Inflnenccd by l~irc Insurance Requirements
1. Influenced by Owner s Special Rcquiremcnts,
such as blast resistance design. as frcqucutly
acquired be; else Telephone Company-.
DIRECT COSTS
Tile "Direct Costs" are the in place' costs
of the various materials which go to make up
the buiTcTing wall. These are usually- shown in
cletaiT on the arcllitect's drawings and can be
rea(lilv; csti~natecl by a general contractor
with the help of Isis various subcontractors.
Exterior walls may be built in ain~ost an
infinite number of contaminations as designers
strive for in~proven~ents in appearance, utility
ancT cost. Each designer approaches the prob-
le~n (lifferently, and as a result sextons are two
builclings built front exactly the sense con~bina-
tions of materials anc] details.
For comparison of wall costs we 1lave ana-
lyze(1 the costs of some buildings of which we
1lave knowle(lge and have corrected them for
Turner Construction Company s Cost Inclex
of July 1956.
Before presenting these, ~ thought teat it
piglet be interesting to give you a percentage
breaLclown of tile various major items in a
building which we built in blew Yorl: in 1L949-
50. To(la~7's buiI(ling average is about the same.
OCR for page 99
Excavation and Foundations .........
Steel France and Fireproofing ........
Brick and Stone 2\I~.sonr~, Windows and
Glazing .......................
Roofing and Flashing ..............
Waterproofing ...................
Interior Partitions ................
N/Ietal Lath and Plaster ............
Carpcntrv and :Millworl: ...........
Miscellaneous and Ornamental Metal.
Cement Finisl~ Floors ...........
Tile Terrazzo and N~Iarble .......
Floor Coverings ................
Painting and Decorating ............
Acoustical Treatment ..............
Finished Hardu arc ................
Security Vaults ...................
Heating. Ventilating and Air Con
ditionin~, .............
Plumbing ..............
Spiring and Fi:;turcs .....
Elevators and Con~cvors ...........
Job Supcr;-ision and General Expense.
4.53~o
16.92
. 8.l:
. 0.45
. 0.36
. 8.29
. 7.37
. 1..26
. 2.~
.. 1.~S
~ ~ -
.. /.~)
.. 0.57
0.69
:.45
0.2/
. 0.60
. . 19.55
.. 5.59
. .10.2S
. 9.12
. 1.40
1 00.00 Yo
In preparing the following cost comparisons,
we lease. unless otherwise noted, considered
only; the following items:
a. 2\/Iasonrx
b. Metal NVorl;
c. Spandrels
d. Windows
e. Dampproofin~, and Insulation
f. Scaffolding
\Ve leave not inclucled such "Direct Cost"
items as Air Conditioning Unit Enclosures, In-
terior Furring and Finishes, Sun Control and
similar iten~s. These are not a feature of tl~e
exterior wall as being considered here, as the
similar designs of each could be usecT with any
type of wall. Further, their costs would not
seriously alter our present comparisons. Tonne
comments will be made later regarding then.
Tile following is a condensecl listing of a
number of unit prices for various buildings
with different walls. The chart below shows
the n~ake-up of each of these walls in snore
detail. :Et must be recognized that these are
only approximate prices to be used very care-
fully. Minor changes in location or condi-
tion Night result in appreciably different
prices.
UNIT PRICES FOR VARIOUS BUILDINGS
Type Location Description
Price/sf.
1. 32-stor~ ofEcc NO Yorl: City Face Brick and Aluminum Sash . .. $ 5.20
2. '-4 story; lab. New York State Roman Brick and Aluminum Sash . . . 5.47
3. 5-stor; l~ospital New York City Brick Caxity \Vall ...... ........ 4.60
4. 25-stor~ office New Yorl: City Limcstonc- Alum. sash and spandrel . . . 7.40
4a. 25-stor~ office New York City Limestone includ. spandrel Steel
windows ... . . . 6.1 5
5. 6-stor; Telephone Near New York City Blast Resistant limestone and cone .... 8.90
6. 2-storx lab. New Yorl; State Alum. Porcelain Enamel and glass 6.30
7. 41-stor~ ofI;ce Pennsylvania Limestone with stainless steel windows
and Steel spandrels 12.30
8.42-stor~ office New York City Stainless Steel with reversible sash 7.20
9. '-story office New England Alum. Stainless Steel Trim and 3/s-inch
Solex Glass . . ............... 11. / 5
10. 2-stor~ office Near Philadelphia Porcelain Enamel Stainless Steel and
Glass 11.60
11. 1-stor; manfg. Virginia Concrete tilt-up and corrugated asbestos. . 1.22
99
OCR for page 100
All of the above prices are per square foot
costs.
In addition to the above we have estimated
the cost of several other types of masonry
faced walls:
I. Marble faced exterior walls using ~s-inch
marble facing and 8-inch common brick
should cost between $7.00 and $~.50 per
square foot provided a normal domestic
marble is used.
2. Granite faced exterior walls using /-inch
thick granite and 8-inch common brick back-
ing should cost about $12.00 per square foot.
3. Mosaic faced exterior wall in the form of a
precast 8-inch Waylite panel of maximum
size-5 feet x 10 feet facet! with Casavan
mosaic would cost from $5.00 to $6.00 per
square foot installed. This panel has a 4-hour
fire rating and Toacl carrying capacity of
about equal to a ~ 7-inch masonry wall.
These prices are for the area of the mason
and do not include windows, glass, insulation,
etc.
INDIRECT COSTS
To discuss "Tndirect Costs" in any detail
would require far more time than is available
Heat Loss through "Window" NVall:
Glass 70 sq. ft.
Insulated Wall 30 sq. ft.
here. However, we believe that a few general
observations might be well worth while.
T. Structural Frame and Foundations
For years Engineers and Architects have con-
sidered the effect of the weight of walls on the
design of the structural frame and the founda-
tions. Little more need be said about this ex-
cept that the influence of the weight of the
wall is far more important in tall buildings
than in low ones and that Pile or other expen-
sive forms of foundations are more influenced
by weight than are rock or high bearing value
soil footings. This problem lends itself to rel-
atively easy analysis.
2. Heating ant] Air Conditioning
The effect of the exterior wall of a building
upon the size and design of the heating and air
conditioning system is very important eco-
nomically and nest be considered by the Me-
chanical Engineer in designing the system. In
studying this effect, we took two building walls
each 8 feet Tong by 12 feet 6 inches high. In
one building we assumed a "Conventional"
wall of masonry and 30~0 glass area. In the
other we assenter! a "Window" wall of metal
and panel construction and 70~0 glass area.
HEAT LOSS CALCULATION
100 BTU/hr. 7000 BTU/l~r.
6 BTU/hr. 180 BTU/hr.
Heat Loss through "Conventional" Wall:
(Masonry portion is 12-inch brick with 2-inch
furring of metal lath and plaster)
Glass 30 sq. ft. 100 BTU/hr. 3000 BTU/hr.
Insulated NVall 70 sq. ft. 6 BTU/hr. 420 BTU/hr.
Excess heat loss through "Window" Wall
One ton of refrigeration equals 12,000 BTU/hr.
Then the added AC load due to "Window" Wall is:
3760 . 12,000 0.3 tons per 100 sq. ft. of wall area
100
7180 BTU/hr.
3420 BTU/l~r.
3760 BTU/l~r.
OCR for page 101
Our calculations apply to the eastern and
western walls of a building. They apply to a
lesser degree to the southern wall and still
less to the northern wall.
The first cost of the heating and air condi-
tioning system for a large building varies be-
tween $800 and $1,200 per ton of refrigeration.
Tf we assignee that variations in wall type would
merely alter the size of the system to a degree
and that the price per ton for the added re-
frigeration would be only 507 of the above
prices, the increased cost of the heating and
air conditioning system in the "window"
walled building will run from $~.20 to $~.80
per square foot of wall more than the "con-
ventional" walled building.
As noted, these figures apply fully only to
the eastern and western walls. Tf these walls
total 30,000 square feet, the increased cost of
the heating and air conditioning system
would be $36,000 to $54,000. In addition the
operating costs go up proportionately.
For a "rule of thumb" we may say that an
additional ton of refrigeration is required for
each 130 square feet of 12-inch brick wall with
metal lath and plaster furring which is changed
to glass. This means that if the acided refrigera-
tion cost $500 per ton, this change costs about
$4 per square foot of increased glass area.
This applies only to the eastern and western
walls.
All of the above figures will vary somewhat
with details, climate, exposure, etc., but still
they indicate how carefully this factor must
be considered when deciding upon a wall
design.
3. Lighting
Tile lighting system of a building must be
designed for the worst condition, which of
course is night tinge operation. An increased
window area does not alter the system. Our
observation indicates that in most offices and
factories the lights are turned on fully in the
morning and turned off by the cleaning force
after they complete the evening cleanup.
Thus, in practice, no operating savings are
obtained.
4. Speed of Erection
It would appear that any kind of panel system
would result in greater speed of erection than
is possible with the conventional type of
masonry construction. We all are familiar
with the spectacular speed of the erection of
the outside skin of several aluminum buildings
in New York City an(1 elsewhere. However,
it should be kept in mind that the speedy
installation of the exterior skin is only one
phase of the construction of the wall. In New
York where masonry backing is required, it
is fount] that the overall spee(1 of erection of
panel walls is not very much greater than the
spee(1 of erection of masonry walls. There
might be some advantage during winter
weather when a rapid enclosure for winter
protection will save some money. It is cliff;cult
to assign a (lolIar value to this item.
5. RentahZe Area
Tf the outside lines of a building are fixed by
property lines or code requirements, such as is
usually the case in a large city, the thickness
of the exterior wall is of economic importance.
The American Standards Association in con-
junction with the National Association of
Building Owners anc! Managers has estab-
lished that the "Net Rentable Area" of a
building space shall be measured to the inside
finish of the permanent outer building walls,
but no deduction shall be macle for columns
and projections necessary to the building.
In the case of a New York City building of
an individual floor area of 26,000 square feet
gross and 19,000 square feet rentable area and
a story height of 12 feet, the wall surface per
story was found to be approximately 10,000
square feet. A decrease in the thickness of
101
OCR for page 102
wall by 2 inches wouIcl Lave acicTecI Ti0 square
feet of rentable floor area per floor. At a
rental of $6.00 per square foot, the yearly
income frown this wouicl have been roughiv
SS40. Taxis suns capitalizec! at 10~,' amounts
to $S,400 or a savings of S4( per square foot
of wall surface.
In considering this matter of wall thickness,
it must be recognized that frequently too
snuck effort is Inane to recluce wall thickness
widen it is not necessary or even clesirable. An
example is in a large builcling built where no
property; line or cocle rcquirc~nents governed
the size of tile buiTcTing. The wall thickness
Was clesignecT clown so much that snore money
was spent clue to close tolerances titan if an
acIditional inch were acicTec3.
mass has the advantage over any; type of light
sandwich wall or metal skin with light weight
backing.
All types of walls neecI maintenance, some
snore than others. Those requiring cleaning,
calking anc! painting or otiose regular atten-
tion shouIcT be analyzecT to cleter~nine the en~-
pl1asis to be given maintenance when co1npar-
irlg wall costs. TIlis is a very complicated anc]
controversial subject. NVe clo not have any
generaliv acccptec! information regarding the
cost of such maintenance programs.
9. Code Require~ne~zts
6. Window Washing Equitnze~t
Whenever consideration is given to cletaiTing
tile walls of a building with fixed glass, proper
evaluation nest be given to the method of
cleaning the windows. In some large buiicI-
ings built recently, machines have been built
to ride rails on the roof ancT drop some form
of car over tile side for the use of tile winclow
cleaner. In some instances this equipment
leas cost over $100,000.
In a number of builclings built since the war,
reversible sash have been user] so that the win-
dow cleaner can stand in the building ancT
wash both sides of tile glass by reversing the
sash. :In one such building it was estin~atecT
that the cost of snaking these sash reversible
rather than fixec] was about $7 ~ 5,000. In this
building window washing machines wouIc:
have I~a(l to be placecl on several levels due to
set-backs, so that close analysis was necessary,.
S_ ~ ~ . .
/. OU17G 1 ransn~zsslon
The transmission of sound through an exterior
wall may be of great importance in some Toca-
tions. Since sound is stopped principally by
mass, the masonry wall clue to its weight and
102
City or state buiTcling cocles frequently; have
requirements which greatly; affect wall costs
ancT must be given full consideration. Often
they require a specific fire rating and so~ne-
ti~nes give actual masonry thicknesses and
material requirements. Wind pressure design
also is important. No generalization of costs
is possible here.
The foregoing is intende(l to indicate that
many factors must be consiclere<1 before select-
ing a wall type. Songs of these are:
a. Aesthetics
b. Publicity
c. Use of the Building
d. Effect upon Strr~ct~re, :Foundations, and 2\/Ie-
cl~anical Installation
e. Economics
Any of these considerations may be estab-
lishecT by the owner as being of top in~por-
tancc. I\To one type of wall is best for all pur-
poses or situations. One owner may select
a wall which is tile cheapest, another owner
one which is outstanding in being clifferent
of modern, and still another owner must have
one which fits into an existing pattern. Only
thorough study will give him the assurance
that Ile has best gained Isis desires.
OCR for page 103
Maintenance of
Industrial Buildings
1MR. REYN-OLDS: Our next speaker is Mr.
MyEre of - the duPont Company. He is a
spect~cations man. He is a designer with struc-
turaZ experience. And he is with a great com
U~TTIL comparatively recent tinges, penna-
nent industrial plant buiTclings were invariably
constructed with masonry walls. Stone or brick
buiTclings offered ~naximu~n fire resistance and
endurance and lent themselves to ~nini~nu~n
maintenance costs. Stone wadis were inherently
thick-two feet or more. Since labor was
cheap, brick walls, too, had a thickness of
twelve inches or snore and provided, in acTdi-
tion to their function as an enclosure, support
for floor sy~sten~s. Thev were ~enernilv solic1
. . .
_ j ., ~ A ~ ~ ~ V ~ J ~ J. A CAL
brick throughout their thickness. Under those
conditions, ~nasonr,v was pretty stable ancT
very little cracking and leakage occurred.
All M. Myhre
E. I. duPont de Nenzours
and Company, I7zc.
WiZmi7zgton, Del.
pony. He is seZf-eclucated anti has been a con-
struction superintendent and a designer. Mr.
AZf M. 1MyEre is a registered professional engi-
neer in Delaware.
The last twenty or twenty-five years have
seen n~arkecT changes in inclustrial cTesign. In-
creased cost of loots labor and material has
clictatec] many of these changes; others resultecT
front new technological requirements which
necessitated more rigid operating conditions.
Tile design of masonry wails has been aRectecI
along with many other buiTcling components.
To accon~plish Tower costs, wall thickness leas
been decreased, while the masonry units the~n-
seives have increased in size. Greater use of
cored units results front an attendant to adjust
unit weight so teat masons can 1lancIle larger
sizes without increased fatigue again an econ
103
OCR for page 104
omy~T~ove. Avails havelargely ceased to func- out wheat we can do to correct or eliminate
tion as such; they have become enclosures .
a skin to cover a structural skeleton.
During the period when all these changes
were taking place, n~any attempts were negate
(and are still continuing) to come up with
satisfactory substitutes for masonry wails. To
ciate, however, masonry retains its position
as the lowest cost, really fire-resistant enclosure
for most kinds of industrial buildings. What
other type of exterior wall can be constructed
for a price as low as $~.50 per square foot ancT
be as durable as masonry?
Yet, some industrial buildings which conic!
appropriate!`; use masonry walls are clesigned
with some other type of enclosure. Why?
There nest be a gin~nick somewhere in the
above statements. Is the quoted cost too Tow?
No: the above cost figure has been repeater!
time and tinge again on our jobs. Fire resist-
ance? That characteristic has never been ques-
tioned. Durability? Masonry is the only form
of wall construction that has endured through
hundreds of years while retaining its original
form. Aesthetic quality? Masonry in its various
J ~
forms and multitudinous color variations
should satisfy the most critical architectural
designer. Maintenance requirements? Maybe:
that's about the only factor left which could
possibly be tagger] with an unsatisfactory
answer.
Masonry is occasionally subject to criticism.
Some of that criticism is justified; most is not.
Even though masonry wails occasionally crack
and leak, we nest ren~en~ber that there are
endless examples of installations which are
functioning in a first-cIass manner and will
continue to do so for decades. AncI, in spite
of the selected accompanying illustrations, du
Months experience, T know, parallels that of the
industry in this respect. However, our particu-
lar subject is "maintenance" so we must, of
necessity, point our discussion to the more
vulnerable characteristics of masonry and find
104
them.
WHY MASONRY WALLS CRACK
Plant walls are frequently subjected to forces
and strains above and beyond those usually
J J
encountered in public or commercial build-
ings. Temperature variations clue to operating
processes may be much wider, affecting both
the superstructure and its enclosure. In fact,
this factor may loom so large that it is imprac-
tical to use anything except a very flexible sys-
ten~. Vibration often dictates special treatment.
The necessity for locating plants at specific
geographical points sometimes introduces un-
usual problems in soil stability and climatic
changes, both factors in masonry wall stability.
The very atmosphere to which buildings are
exposed may be contaminating and highly
corrosive. Even though masonry is highly re-
sistant to the effect of most chemical fumes,
cases have been experienced where brick walls
have failed completely from internal build-up
of sulphate crystals and allied chemicals.
Many of the above conditions dictate the
use of special (resign techniques. The same
procedure may not work in any two similar
situations. Consequently, these are special
problems requiring special solutions. However,
there are two elements that work both sepa-
rately and together to destroy the integrity of
masonry walls and against which specific pre-
ventative measures can be repeatedly effective
namely, changes in moisture content and
variations in the temperatures to which ma-
sonry is exposed.
All masonry is subject to moisture absorp-
tion to some degree. It is always affected by
temperature changes. Peculiarly, moisture and
temperature produce exactly the same di~nen-
sional changes-an increase in either or both
causes expansion, while a decrease causes
shrinkage. Not only that, high temperatures
are frequently accompanied by heavy precipita
OCR for page 105
tion so that the effect of both temperature
increase and moisture absorption takes place
at the same tinge and is cumulative. In addi-
tion to these results, dimensional changes in
the steel supporting structure resulting front
temperature variations exert forces on ma-
sonry which create large differential move-
ments. The thermal coefficient of steed and
concrete, for example, is up to 2~/2 times that
of masonry. The forces acting on masonry
walls, both front within ancT without, some-
times exceed the n~asonry's compressive
strength while it tensile strength, as well as the
bond strength of mortar, is aIn~ost always ex-
ceeded when reactive movements are devel-
oped. A wall which is restrained by its support-
ing structure or its own mass invariably cracks
when shrinkage takes place.
When a wall cracks, return to its original
position is cut short. During the second and
succeeding cycles of temperature and moisture
changes, particles of mortar and masonry units
drop into the crack to partially fill it so that,
at maximum elongation during the next cycle,
the position of the wall is somewhat farther
along the support than it was at the peak of
the previous cycle. Thus the results of cyclic
changes are cumulative. Sonnetizes, evidence
of cracking is difficult to detect because the
change has produced short, thin openings dis-
tributed over wide areas, but if a wall leaks,
they are always there.
Two types of cracking are involved. One is
identified by opening of mortar joints at the
interfaces of the masonry units resulting in
hairline cracks which do not necessarily extend
from brick to brick. Such openings form chan-
nels for infiltration of water by capillary action.
The other kind of crack is recognized (l ~ by
its size which varies from hair line width to
that big enough to "lay a hand into," and (2)
by its direction and course which frequently
is directly through brick without regard to the
position of joints, or zig-zag from brick to
brick and course to course. The first type is
caused by shrinkage in indiviclual masonry
units, accon~panie(1 by poor adhesion of joint
mortar and the use of mortar having high
shrinkage characteristics. The second type is
caused by shrinkage of whole sections of the
walls, together with the results of differential
movements restrained by collateral construc-
tion.
About three years ago our company initi-
ated a study to find out why we were getting
adverse comn ents on masonry walls front the
operating management of some of our plants
and to determine the procedures which wouIct
eliminate recurrence in our new buildings.
Many plants in widely separates] locations were
visited. The condition of their masonry walls
was closely exan~inecT and the causes for crack-
ing analyzed. Let me show you some of what
we found.
Figure ~ shows one wall of the cafeteria
builcling at one of our plants. This builcling as
well as all others at this plant has composite
walls with brick facings and sn~ooth-faced hol-
low tile back-ups in a total thickness of eight
inches. Most columns were encased, with the
tile or brick in intimate contact with column
105
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Representative terms from entire chapter:
public buildings
Maintenance
of Public Buildings
M R . R E Y A- O ~ D S.: ~ 30 not believe there
is a anon in America who knows more about
the operation of buildings than the next
speaker, lA1r. Charles A. Peters. He is the Di-
rector of the BuiZ~ings Management Division,
PubZic BuiZ1ings Service, General Service Ad-
n~inistratio~z of the United States Govern
nzent.
Mr. Peters has been e~ntZoyed by the PubZic
BuiZ3ings Service and its predecessors since his
service with the Bureau of Yards and Docks,
United States Navy, during Worm War T. He
is a Bachelor of Civil Engineering from the
University of Michigan and ~ newer of the
Charles A. Peters
Public Buildings Service
General Services Administration:,
Washington, D. C.
An~erica~z Society of Civil Engineers, the
Society of American Military Engineers, the
Illuminating Engineering Society, several code
committees of the American Standards As-
sociation and the International Municipal
Signal Association.
He is also ~ member of the Washington
Building Congress, the Building Owners and
Managers Association, Washington Society of
Engineers, BuiZ1ings Management Associa-
tion, Government Services, Inc., Federal Safe
ty Council, Federal Fire Council, The Wash-
ington and MaryZan<] Societies for the Blind,
and the P.B.S. Welfare Service, Arc.
~ His paper is a report of experience asso- are basic in tile design and construction of
ciated with 36 years of living with the prob- public buildings.
Tents of builcling
n~aterials that the architect and engineer will
use in erecting their structures. From my ex-
perience. ~ believe we are still limited in our
conclusions drawn from tests, ant! that time
and nature's forces still produce the conclu-
sions that are universally accepted.
Having been asked to participate in the
Conference on Modern Masonry, T have ap-
proached the subject from the viewpoint of
consenting on the n~aterials that are used in
public buildings to enclose the buildings and
to partition the buildings.
The maintenance engineer, probably snore
so than the architect, becomes conscious of
operating costs. He can evaluate mistakes in
design practices and quickly observe the cle-
fects in workmanship and those resulting from
poor inspection. He navy take the tinge to pass
back to the buiTcling designer and the pro-
ducer of materials, corrective suggestions or
information that would alert them to errors in
design or in manufacture. The usual course,
however, scene to be to live with the mistakes
and to attempt corrective alterations and re-
pairs.
\Ve do review our design practices, such as
design details and specifications, periodically.
Recently a committee of seven experts was ap-
pointed to study and report on the documents,
criteria, and practices that establish design
and construction standards of public build-
ings. Their objective was to bring the existing
standards in line with good con~n~ercial prac-
tice consistent with Federal requirements and
to insure n~inin~un~ operational and n~ainte-
nance costs.
it may be of interest to repeat a sentence
front the con~nittee report that relates directly
to the subject. The contingent concerns exterior
facings. "Public Buildings Service should not
experiment with any particular type of con-
struction but shouIcT use proven materials to
assure n~inin~un~ operational and maintenance
costs."
116
EXTERIOR WALLS-
DESIGN AND CONSTRUCTION
When selecting the materials for exterior
walls one thinks in terns of durability, ap-
pearance, weather-tightness, unit cost of n~a-
terial in place, and Tow maintenance cost.
There are other factors that are important to
the architect, possibIv classed loosely as the
aesthetic requirements, but to those respon-
sible for maintenance and operation, n~ate-
rials requiring minimum maintenance are
ideal.
Granite brings to mind a material that is
ageless. It is used today by the architect for
a partial treatment of the exterior of a buiTc3-
ing. It has some disadvantages in today's con-
cept of a public buiTcling, and these are Eight
and first cost. On the other hancI' tile build-
ings we operate that are granite faced are
practically free of maintenance costs for stone
work.
I.inlestone is the most widely used stone
for exterior treatment and when selectee} for
qualities of hardness, surface texture, and re-
sistance to moisture, is on a par with the other
materials for beauty in design and Tow n~ain-
tenance cost. It is one of the outstanding stone
materials for a public building.
Marble as an exterior treatment is one with
which we have had lin~ited experience. There
are a few public buildings that are n~arble
faced but it is a stone that lencis its beauty
to interior finishes. Where extremes in weath-
er are not conditions that have to be consicI-
ered when selecting exterior stone, marble is
an excellent stone with low maintenance cost.
Sandstone has been used to some extent for
exteriors on such builclings as the White
House, the center wing of the Capitol, the
Court of CIain~s, and other public structures.
it is most successful in this use when kept
painted.
Brick as one of man's oiclest buiTcling n~a-
terials is an excellent treatment for exterior
use. We have notary brick faced) buildings
which give excellent service front the stand-
point of Tow maintenance cost. This is one
material that requires careful inspection clur-
ing construction if the buiTcling wails are to
remain free of water. The entrance of water
has been our principal source of trouble and
the most difficult to correct. The cause is us-
ually poor workmanship or skimping on the
vertical joint mortar. We have exan~ples of
this at SuitIand, Maryland.
Terra cotta has n~anv qualities to recom-
~nend its use in builclings. Its history, however'
as an exterior building n~aterial, records many
instances where trouble resulted front design
defects, anchor corrosion, failure to consicler
climatic changes, and installations that were
ctiflicult to reach ant! maintain. As a n~an-
~nade n~aterial, it readily fits into arcLitec-
tural concepts and can be so rnoulded.
Concrete exterior walls have not been too
well received when considered in public build-
ing design. In some parts of the country, con-
crete builclings for public use have been con-
structed which are achitecturally beautiful. In
the limited experience we have had from the
standpoint of maintenance, this exterior treat-
~nent appears to have Tow maintenance cost.
Our niacin difficulty has occurred in designs
which did not fully allow for temperature
changes and resulting movement in the span-
clrels. Our Federal Warehouse, here in Wash-
ington, is an example.
Stainless steel as an external facing mate-
rial has not been one of our problems. It is
too new and wit] have to prove itself as a pro-
tective skin before it has wide acceptance with
architects of public buildings.
Glass in the form of panels or blocks is not
a n~aterial that has been used to any extent for
the exterior treatment of public buildings.
EXTERIOR WALLS MAINTENANCE
Maintenance problems that have concerned
us in connection with exterior stonework have
been widespread geographically. They result
,fron~ climatic changes, design weaknesses,
poor workmanship, and inadequate inspection.
The materials used for setting ant! pointing
have also player! a large part in contributing
to our problem, and in some instances the
corrosion of anchors has produced major fail-
ures.
Poor inspection can be cleaned in a nun~-
ber of ways, but our experience indicates its
cause stems from too much reliance on the
workman to conform to design details that
are not fully understood, limiter! funds to hire
qualified inspection personnel, and leniency
on the part of the men responsible for getting
what was intended.
Specifications should include the require-
n~ents that will adequately describe the n~a-
terial and assure rejection of faulty pieces.
Material inspection is very important if we
are to obtain the quality material specified.
Considering stonework from the viewpoin
of installation we fins! that poor workn~an-
ship, unsatisfactory bonding materials, and
lack of protection of the work during con-
struction are the principal sources of trouble.
The tendency to use high-strength mortar
usually results in poor bone! with the masonry
units. Shrinkage quite often destroys the bond
between the masonry units.
Mortar design or formulation has been
widely investigated but it still remains the
weak point of a n~asonry-faced structure. Pos-
sibly because it is relatively simple to prepare'
it remains a point of weakness. Much can
and has been written on the subject, still it is
the principal cause of the need for periodic
maintenance of stone work.
Much greater success has been attained with
brickwork than with stonework from the
standpoint of mortar design. Here the chief
trouble has been the difficult task of trying to
get sur~cient mortar in the vertical joints.
117
Where pointing mortar is used, there is a
tendency for a crack to clevelop between the
mortar and tee masonry unit which admits
water. Where a rich mortar is useci, tee stone
on one sicie of the joint wit} often spell off.
These difficulties have lee! to the use of
calking compounds in many cases. Calking
~natcriaIs have been ancT still are relatively
short liver! in maintaining a perfect seal. View
formulations appear frown time to tine, but
tee period of effectiveness is quite short when
exposed to the sun. Revere calking materials
are required, teeny shouIcl be usect where in-
spection is easy and repairs can be oracle with-
out too much clil~culty. Design shouIcT be such
as to eliminate the pocketing of water when
the calking material fails.
Waterproofing materials Lave receixiec] carc-
fuT consideration when we faced the problem
of camp walls or walls that permit the pas-
sage of water. Talc materials so ciassifiecl have
a relatively short life before requiring acicTi-
tional treatment. This is particularly true
when exposecl to the sun. T ant of the opinion
there is still no silent cut to a weather-tight
structure except by the use of souncT materials,
skilIfully placecT ancT clesignecI to cTevelop their
full capabilities.
Metal skins, Allen they Second accepted in
tile saline sense as we accept stone-facecT struc-
tures, will bring their own problems of ~nain-
taining a weather seal.
Glass panels anc] blocks oder features that
will intrigue tile architect anc! may be usecT
more extensively in the future. Whether they
wit} solve the problem of maintaining a
weather-tigI~t building anc! one which will be
economical to maintain and operate, remains
to be seen.
EXTERIOR PROBLEMS
When considering exterior problems we all
agree that the parapet wall is our principal of-
fender and produces more troubles than any
other part of the buiTciing. Since the parapet is
118
more exposed, it is subject to greater expan-
sion anc] contraction than any other part of
tile building. This probe of expansion, to-
gether with flashing difficulties, nouns leaks,
water infiltration, freezing, anchorage failure
anc! masonry cracking and clisplace~nent.
Tl~e solution is only possible through the
most careful consideration in the design and
construction of the Nan; details involvecl, witl1
verse special emphasis on expansion. We be-
lieve tile best solution, where possible, is to
omit the parapet ant! our present revised
stanciards so provide.
An example of this problem occurrec! in tee
Seattle Court House where the exterior terra
cotta facing of the building has been seriously
cian~agecI, water getting in through the para-
pet due to inadequate flashing ancT counter-
flashing. Tile moisture 1las penetrated tile e:;-
terior wall, causing cliscoloration of the terra
cotta and leakage on the interior ceilings.
Tile probIcn~s that develop tI~rougl1 i~nprop-
cr anchorage or failure of anchorage, usually
through corrosion, are many ancT their cor-
rection is very costly. ~ could sight many ex-
angles but the following three in clifferent
types of masonry will illustrate the problem.
In the Cleveland Post Office the exterior
fluted stone pilasters, througl1 improper an-
chorage and support, ca1ne loose and some
were projecting due to frost action. Since
large stones were involved high on the exterior
face of the building, a very expensive job of
resetting and anchoring resulted.
In Dallas, Texas, tl~e brick pier facing bc-
tween the 14tl~ and 15th floor levels of a 19-
story building fell on the roof of an adjacent
3-story building. It was found that the brick
facing was improperly anchored to the struc-
tural framework. The cost of rebuilding and
settling claims was in excess of $700,000.
In Chicago tile three upper stories of the
America-Fore Building were faced Title terra
cotta. Water entering through tile joints cor
roded the anchors and several large sections
fell to the street below. Luckily no one was
injured, but the entire three stories of facing
hacT to be removed and replaced at a cost of
several hundred thousand dollars.
If stone walls are to be kept titlist, a
planned program of exterior pointing and
calking is necessary. Careful inspection is
needed to determine how often this must be
undertaken. We have not been able to de-
velop a formula that would apply since man;
factors, including exposure, size of stone, type
of joint, kind of stone, and quality of original
work, all play a part in the life of pointing and
calking. NVe have found that most struc-
tures will require some pointing at least every
ten years and some calking every three years.
Strange as it may seen, we have had to re-
pair ciamage caused by lightning. One ex-
an~ple is the General Services Building where
several hundred dollars in Manage resulted on
two occasions front strikes on the parapet wall.
Buildings like the Washington Monument
ancT the LincoIn Memorial have elaborate
lightning rod systems properIv grounded to
prevent Bandage.
Time will not permit any covering many
other problen~s, such as that introcluced by
birds roosting on buildings, lent they are many
anct varied.
INTERIOR WALLS- CONSTRUCTION
Interior construction problems that occur
frown occupancy changes are usually the result
of organization changes in the tenant agency.
The clay is gone when the architect can Cornily
plan on how the interior space of a public
builcling will function. Verb often before the
contractor has completed his work, changes
are called for that are costly. Why, you may
ask, is this permitted? The reasons for the
changes are usually sound and functionally
ciesirable. Recognizing this situation, it is nec-
essarv to plan carefuliv the use of interior
J ~
partition materials.
Since weather is no longer a problem with
interior walls, the bonding materials are not
too critical. Maintenance is minor, and the
more costly materials can be justified on the
basis of permanency in many locations. When
repairs are necessary;, the cause is abuse or
faulty workmanship.
Materials such as marble, limestone and
brick can be used in constructing main corri-
dors, elevator lobbies, service and mechani-
cal areas. Our experience indicates that marble
has decided advantages in lobbies and main
corridors.
Marble is very attractive for such use, re-
quires very little maintenance, is easily cleanest,
and will stanct reasonably hard service. Wllv
people abuse interior walls by placing their
feet against then, writing on then, or other-
wise defacing tureen is hard to understand, but
they do, and marble surfaces will take that
abuse without serious damage.
Granite can be used where Bandage is quite
probable or service may be very severe. Glass
block and glass panels are clesirable in songs
locations because of low maintenance and
cleanability. The sense is true of terra cotta for
floor surfaces and for decorative treatment in
corridors, lobbies, auditorinn~s, and public
areas.
INTERIOR PROBLEMS
Speaking of tile floor surfaces ren~in(ls nice
that the design and construction cletails must
be planned to insure low maintenance and
operating cost. An example of the wrong solu-
tion exists in the Interior Building, here in
Washington. The joints between the floor tile
are about 3/8 of an inch wide and were slightly
depressed to allow for any irregularities in the
surface of tile.
Tile result was a very attractive floor but.
when we began to clean the floor with a power
scrubbing machine, we found a serious defect.
The machine which uses a squeegee to remove
the water would not pick up flee water front
119
the joints. This resulted in the use of a see- the tenant should be satisfied because the
ond Plan to mop behind the machine, thus architect knows best. As an operator, I quickly
requiring two men to do the job instead of learned the tenant had ideas of his own. Many
one, and doubling the cost.
The type of n~aterial to be used for interior
partitions dividing the office space into rooms
has received a great deal of study frown the
operating man in recent years. We have used
masonry partitions, metal and wood ceiling-
high n~ovable partitions, Tow-height movable
partitions. and the dry-wall type of partition.
We have sought a low cost solution that
would insure n~axin~u~n flexibility.
Eve have about concluded that there is no
one solution for all buildings and all types of
occupanc!. NVe find that each propylene re-
quires study. In some types of occupancy, we
found that we did not move partitions as often
as was expectecI. Some tenants could use the
low-type partition witty good results while
this type partition completely disrupted the
work of other agencies.
OPERATOR S VIEWPOINT
Front the viewpoint of the manager ancT
operator of public buildings it is very i~n-
portant to know materials and to observe how
they were specified to be used by the architect
and engineer. This knowledge can be partic-
ularly useful when repairs, alterations, anc!
maintenance problems are resolved. To ob-
serve weaknesses in clesign details and speci-
fied materials is important. Suggested i~n-
prove~nents will be particularly helpful to tile
design once to prevent tee repeating of ~is-
takes.
PreviousIv ~ referred briefly to tile special
co~n~nittee of experts and their caisson. The
operating people worked witty that con~n~ittee
when they reviewed specifications and design
details and directives, which required chang-
ing, to correct faults and improve future de-
signs.
Too often the architect has the view that
120
in~prove~nents that develop lower operating
costs originate frown tenant suggestions or front
the operating organization.
C OSTS
Operating costs of Federal buildings are
subjected to careful review by the Bureau of
the Budget and by the Congress. The con-
tinuing study to arrive at still Tower operating
costs challenges the ability of the operator. In
searching for tee newels to accomplish this
objective without cutting service, the operator
must focus his attention on the materials of
wl~icl1 the building is constructed as well as
on the design of the building itself.
Because a Federal building 1las an indeter-
~ninate life, that is, it is not planned and not
constructed for a specified number of years'
new materials are subjected to searching in-
quiry before Ploy can replace materials that
are "tine proven." This may be disturbing to
some manufacturers but it is necessary. The
architects that design Federal buildings are
aware of Ellis widen they create their design.
It does not mean the absence of progressive
construction or ignoring new concepts in cle-
sign, but it does mean tl~e use of the building
materials that leave withstood the test of time
in public buildings.
Maintenance costs of specific materials are
very difficult to tie down because they clo not
occur annually. Fallen failure takes place due
to faulty design, poor worl~n~anship, or the
presence of materials that should have been
rejected, costs that are sizable in amount may
occur. Even here, they are so scattered geo-
grapl~ically and by years, that the costs are
usually not a large part of the operating budget
but are certainly an unnecessary part Chicle
we would like to eliminate.
Discussion
MR. REYNOLDS: The first question is ad- the roof to interior locations or gutters that
dressed to Mr. Noyes. it reads '`$1.72 for would be of ample size. :Et is usually done by
tilt-up wall. Does this include sash and equip- sloping the roof to interior downspouts.
went, surcharge for lifting?"
MR. NOYES: It does. It includes the tiTt-
up section it includes the corrugated asbestos,
which was used as dividers between windows
and above the windows, and it includes the
sash itself and the glass. It was a complete
wall for that purpose. There was no interior
finish, there was no fanciness to that wall. It
was a straight industrial wall.
MR. REYNOLDS: The next question is to
Mr. Mybre. What is the relative importance
of moisture and temperature movement?
What is the order of magnitude of moisture
expansion in brick walls?
MR. MYHRE: Well, that is a little difficult
to answer. It seems that there are no ciata that
T have ever seen that have set up the results
or that have graphically set up the results of
moisture absorption or expansion frown ther
MR. REYNOLDS: The next question is to
neat changes. We clo not know that as far as
Mr. Peters. If we omit the parapet, how do we
thermal changes are concerned, there are fig-
handIe sullen heavy rains, cannon In south-
eastern states?
M R . P E T E R S: We conic accomplish that
through the design of the roof in directing the
water to suitable downspouts, either sloping
ures which vary all the way from, ~ think it is,
.000003 to .00000S inches per foot.
MR. REYNOLDS: The next question is to
Mr. Noyes front Mr. Rearclon. Is reinforced
brick masonry used extensively on the west
121
coast for single-story construction? How cloes
it compare with (a) tilt up, (b) poured in
place concrete, ~ c ~ gunnited walls?
MR. NOYES: )'n] afraic! ~ cannot answer
that. ~ have no connection with the west
coast, any experience is entirely on the east
coast, anc! we have not used reinforced brick
work to its full extent. We have reinforced
odds and ends here and there, but not to any
great extent.
Me. REYNOLDS: Now, here is a question
from Mr. Rearclon of G.E. to anyone, but I'm
going to address it to Mr. Myhre, because we
were talking about the subject before the ses-
sion began.
If mortars are such an important part of
tile masonry wall, ~ would like an expression
, . .
Ot opinion on masonry cements versus port-
lan(l cement tinge putty, or hydrate lime.
MR. MYHRE: ~ don't think T have ever
been in a conference or in an assembly of
engineers and architects where that question
has not cone up.
~ awn going to give you nay own personal
opinion. :Now, this can be taken for what it
is worth, and it nest be consiclered my per-
sonal opinion and not reflect on anything that
anybody else is connected with.
~ think that high Tinge mortars are the most
effective mortars. ~ do not think that masonry
cements consisting of Portland cement and
ground limestone will be suitable in most
cases. ~ think that masonry units having a Tow
moisture absorption characteristic could very
well use that type of material. However, when
the absorption rates become higher, we neec!
the qualities that Tinge can produce in the mor-
tar, and very- few masonry cements use Tinge,
that is hydratec] Tinge, in their n~asonrv; mortar.
MR. REYNOLDS: The next one is for Mr.
i\:oyes. In your opinion, can money be saved
in one- and two-story buildings-schools, offi-
ces, etc. by using load-bearing n~asonr`; rather
than frame structures?
122
MR. NOYES: Our experience with frame
structures is rather meager in recent years. T
don't think this question can be readily an-
swereci. Many factors have to be taken into
account, such as maintenance and various
other angles. ~ believe that frame wouIc! be
cheaper, but ~ don't think it would be as sat-
isfactor,v.
MR. REYNOLDS: ~ have two or three more
questions of Mr. Myhre. Here is one from the
Dow Chemical Company. ``What type of
waterproofing do you recommend? What ma-
terial do you use in expansion joints2"
MR. MYHRE: There is only one water-
proofer that is satisfactory in my estimation
and that is the silicon waterproofer. None of
the other waterproofers will approach it in
sealing the pores and hair cracks in masonry
walls. :[ know Dow makes that material as
well as General Electric. We do not.
Now, there are new truly elastic or synthetic
n~aterials on tile market today which are a
great deal better than the old oil-base type of
calking compounds. T am referring to such
materials as glycol. We ourselves are develop-
ing one that we think will do the job at a
little bit less money, possibly, than glycol. But
these materials will last a great deal longer
than the old compounds- four or five times
longer, in our estimation. We have tested
then for three or four years now and their con-
dition is almost the same today as the day they
were applie(l. We think the worIcT of them.
It costs a little bit more when you first apply
it, but the over-all cost is much less.
MR. REYNOLDS: Now, Mr. Myhre, ~ have
two questions here which T ant going to com-
bine into one.
Tile first one is can you describe the expan-
sion joint or control joint as shown in your last
stifle. And the other one is what is your rec-
omn~enclation in regarc! to the use of through-
wall control joints, in addition to expansion
joints, for controlling cracks in long masonIv
walls.
M R. M YHRE: When you leave walls con- rubber. or something that will cone back again
sisting of a brick facing or some type of hollow when the wall shrinks, and is sealed on the
masonry unit' we will say, for back-up, the
type of joint is almost automatically designed.
Of course, it must extend all the way through
the wall. It cannot be just through the facing.
We generally place then on colognes, so that
both sides of the wall can be supported with
flexible ties to the colognes. The joint is usually
outside surface at least with a calking com-
pound. Now, if the old type of calking con~-
pounds were used, and that was the case in
that last slide, it is necessary to protect that
compound frown the weather. And that was
the reason for the plate that you saw, which
was fastened only on one side. It kept out the
three-quarters of an inch wide as a minimum- rain and the sun and would make tile old type
maybe a little bit more, depending on the of co~npoundlast tl~atn~uch longer. We don't
length of the wall. The joint is sealed with an think they are necessary with the new
elastic, very elastic, material, such as sponge materials.
123
