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BY EDWARD G. LE JEUNE*

To pre p a re a concrete estimatep roperly for bidding purposes

the estimator must consider twofacets of an estimate. The first is thequantity takeoff; the second is thep ricing schedule. The quantity takeoff must be done by the sameman who is to price the job or atleast by someone who uses the

same system of takeoff as the one who prices it. This is especially truein form w o rk quantities. Wi t h o u tthis understanding between the“takeoff estimator” and the “pricing e s t i m a t o r” errors are intro d u c e dthat can make the bid either toohigh (and there f o re useless) or toolow (and therefore expensive).

A quantity takeoff of all items of c o n c rete is the first step in pre p a r-ing an estimate. All items of concretem a t e rial are listed on the quantity

takeoff sheets. Since the concre t e y a rdage in a job is the most impor-tant item, I get this down first along with related form work, hand excava-tion, finishing and other items thatcan be gathered at the same time toexpedite the takeoff. Most miscella-neous items can be worked out fromthe above quantities. No deductionf rom concrete yardage is made forreinforcing steel.

The next step after the “takeoff” isto pre p a re a recapitulation sheet. With a job properly “taken off” the“recap” sheet can be prepared by ei-ther the “t a k e o f f” or the “p ri c i n g”estimator since each understandsthe method followed. Items are list-ed under the following major head-ings:

FormsConcreteFinishingHand Excavation and Sand Fill

Miscellaneous ItemsIf re i nf o rcing steel and mesh are

to be included add them as a sub-item.

The final step is the pricing of the work. This, of course, is the impor-tant step. Many estimators can bet rained to do “takeoff work .” Ve ry few are qualified “p ricing est ima-t ors.” A qualified pricing estimatorshould be able to show how he ar-ri ved at eve ry unit price he used.The unit price may be off to somedegree but he should have a logicalreason for using it.

Now, if you have a small concernand if you have all close fri e n d s

working for you, you can figure on ahigh production ra t e. Since yo u’regetting much more work out of yourmen than the ave rage contra c t o r you can do the work for a lower feethan the ave ra g e. Once you getm ore than about a dozen men, yo ushould figure work at an ave ra g e

rate of production. Stop figuri n g maximum production at this pointbecause the ave rage man will notgive you maximum production.

I base my figures on how many square feet of form work of a certaintype an average man can do in a day.Once I know that, I can come up with how much it costs this year orany year.

The Concrete Estimating Outline,Table I, is not at all unfamiliar to ac o n t ra c t o r. It’s just in a form thatlogically follows all steps in taking off a job. For example, let’s say you’refiguring only slab work. In this case,skip everything else that doesn’t ap-pl y. There isn’t one job that has all 21items on it, but the outline will serveas a reminder and as a guide as yougo through this series of articles.

I ’m not going to tr y to cram my ideas into your mind. I might—in

estimating wall forms up to 4 feeth i g h — f i g u re that a man should doabout 300 to 350 square feet a day. If you know that you get 400 or only 200 square feet a day, you can stilluse this system, apply your own fig-ures and use your own labor rates tocome up with the correct labor costper square foot. I base all my costson a carpenter and half a labore r’sra t e. I’m figuring that you run theaverage crew with a ratio of two car-penters to one labore r. That willhold true for all of your larger jobsand for many of your smaller jobs,but not too long ago a concrete con-tractor told me that he used one car-penter to two labore r s. That’s allright; he can use this method any- wa y. All he has to do is add a carpen-ter’s rate to two laborers and use hisproduction, but he has to rememberthat probably he doesn’t get thesame production out of a carpenterand two laborers that he does out of

two carpenters and one laborer.For checking extensions and ad-ditions I use the following method which I highly recommend. When-e ver I extend anything on a ma-c h i n e, I always mentally calculatethe answer first. This prevents a dec-imal point error. For instance if thea n s wer was 225 I might get 240 if Ipunched the wrong number on the

A Guide For Concrete Contractors

ESTIMATING CONCRETE WORK—1

The author, a civil engineering grad-uate from Univeristy of Notre Dame,has been estimating concrete workfor the past 17 years. For eight of these years, Mr. Le Jeune was pres-ident of his own estimating service. The author presently is associatedwith the W.E. O’Neil Constru c t i o nCompany, Chicago, Illinois.



machine and I wouldn’t know it, butI couldn’t get 24, because I wouldknow in my head that I’ve got an an-s wer coming in the hundre d s. Inother word s, if yo u’re multiplying 150 by 125, well, in your head yo uk n ow that 150 times 100 is 15,000,so you had better be somewhere inthe thousands, because if you get

1,500, you know you are wro n g . When adding a column of figures Iadd the total down the column of figures and write the answer. Then Iadd the total in re ve r s e, or up thecolumn of figures and put a check-mark at the first answer, if the totalsa g re e. It is ve ry difficult to have amechanical error using thismethod.

Column foot ings

In general that’s an introdu ct i o nto my technique of estimating con-crete. Now we’ll get down to the ba-sics, and we’ll start with the quanti-ty takeoff.

Item number 1 is column foot-ings. Here I have marked hand exca-vation area, forms and concre t e.This may sound a little elementary to some but to others it may not. By column footings I mean individualfootings, not anything that’s contin-uous under a wall; wall footings arecovered under item number 2. Un-der column footings we pick up allthe individual footings including afooting for a chimney. It might be 6feet by 4 feet by 2 feet thick. Pri c e-

wi s e, this is an individual footing. Ishould point out here that I sepa-rate the quantity takeoff by items inorder to get everything into the cor-rect price bracket. In other words, acolumn footing 4 feet by 3 feet by 1foot thick is in the same price brack-et as a chimney footing 6 feet by 4feet by 2 feet. The system is flexible

because under the heading “c o l-umn footings” you can include any other individual footings you want.

For the hand excavation area I always take the exact area of the foot-ing. In other word s, after the ma-chine excavator finishes, he leaves itcut down to plus or minus 1 inch. You’ve got to go in with hand laborand cut the bottom down to the

1. COLUMN FOOTINGS: hand excavated area, forms,concrete.

2. WALL FOOTINGS: hand exc avated area, form s, 2by 4 keys, concrete.

3. FOUNDATION WALLS: forms (in 4-foot heights), 2

by 4 keys, slab seat bearing, and concrete.4. PIERS BELOW GRADE: forms, concrete.5. BUILDING SLABS ON FILL: sand fill, edge forms,

expansion joints, finish area, and concrete.6. EXTERIOR COLUMNS: forms, concrete.7. INTERIOR COLUMNS: forms, concrete.8. EXTERIOR BEAMS: forms, concrete.9. INTERIOR BEAMS: forms, concrete.10. SHORED FLAT SLABS: slab form s, edge form s,

finish area, concrete.11. METAL PAN SLABS: slab forms, edge forms, finish

area, concrete.

12. SLABS ON CO R RU G ATED FORMWORK: corru-gated form work, edge forms, finish area, concrete.

13. STAIRS ON FILL: sand fill, form risers, finish treadand riser, concrete.

14. SHORED STAIRS: form risers and stair bottom,

finish tread and riser, concrete.15. STAIR LANDINGS: forms, finish, and concrete.16. PAN FILL STAIRS: finish, concrete.17. MISCELLANE OUS CONCRETE IN BU I L D I N G :

forms, finish, concrete.18. EXTERIOR SIDEWALKS: sand fill, edge forms, ex-

pansion joints, finish, concrete.19. EXTERIOR PAVING: sand fill, edge forms, expan-

sion joints, finish, concrete.20. EXTERIOR STRAIGHT CURBS: hand exc a va t e d

area, forms, finish, concrete.21. EXTERIOR CURB AND GUTTER: hand excavated

area, forms, finish, concrete.

OUTLINE FOR CONCRETE ESTIM ATINGTable I

Quantity Takeoff

FORMS: all form w o rk items from takeoff. total of form work for stripping, cleaning. CONCRETE: all con-crete items from takeoff. total concrete for testing.

FINISH: screed material: total finishing area forbuilding.

float finish: from room schedule and from specifica-tions.

straight trowel finish: screed material less float finish.all other finishing from takeoff.

hand rubbing: exposed surf a c e s — f rom dra w i n g sand specifications.

E XC AVATION: hand excavation from takeoff.sand fill from takeoff.M I SCE LLANEOUS: check specifications and dra w-

ings completely.add curing slabs, hoist, heat protection, cleanup,

sawman, foreman.add insurance and taxes at 13 percent times labor,

and overhead and profit.REI N F ORCING STEEL AND MESH: add as subitem

with overhead and profit.FINAL: list of: included and not included items andalternates.

RECAPITULATION SHEET AND PRICING



g rade that you need. I always takethe exact area for the following rea-son: Once I have the width times thelength I have the footing area. If Imultiply by the depth I have thec o n c rete vo l u m e. We know thatthe y’re going to hand excavate a lit-tle bit wider than the exact footing a rea, but this you can take into ac-count with your pricing unit. Co n-c rete is not a sim ple thing to takeoff. You’ve got to break it down, stepby step, as it would be built. Thismethod isn’t anything new or revo-l u t i o n a ry; all large contra c t o r sshould be following this system in

one form or another. But the point isthis: the quantity takeoff should besimplified as much as possible in or-der to get the answers as quickly asp o s s i b l e. To determine the form-

w o rk re q u i red for column footingstake twice the width plus twice thelength times the depth of the foot-ing. This gives the contact area of f o rms re q u i red. All form w o rk

should be taken off and priced onthe basis of contact area. This willmake it easier to t akeoff and re c a pquantities.

On the quantity takeoff sheet w rite down the number of columnfootings required of each size. Fromthese figure s, extend the totals forhand excavation area, concrete vol-ume and form w o rk are a s. Thesethree totals are extended to your lastcolumn on the right and checked off thus ( ) meaning that they are to beextended again later to your re c a psheet for pricing. Always list the to-tal number of column footings. It is

easier to price column footings if you know how many are invo l ve d ,and by figuring that a man shouldf o rm so many footings of a cert a i ns i ze in a day. This gives the for marea per day.

Wall footings

Wall footings, item number 2 onTable I, is next. The system used for

figuring column footings should al-so be used to figure wall footings.Take off the quantities for hand ex-c a vation are a s, form s, 2 by 4 key- ways and concre t e. When you takeoff wall footings the first thing to dois to separate all the wall footingsthat are the same as far as width anddepth are concerned. In other words, check off all 1 by 2 foot foot-ings and if you find 50 feet here and60 feet there and 40 feet somewhereel se, add them together. Ha ve yo urown system of checkmarks on thed ra w i n g s. I don’t like to mark upd rawings with different colore d

pencils because of the trouble itmight create for the next man whouses it. It is also a waste of takeoff time. I just put a little pencil check-mark on the footing. When you havetaken off and marked all of the wallfootings on your quantity takeoff sheet, it is easy to extend the totalsfor hand excavation area, form work,2 by 4 keys a nd concrete from the

Column Foot ings or Box Footings

Square Feet Square Feet Cubic Feet EstimatedNo. Description Number Dimensions Area Forms Concrete Quantity Unit

1. Column Footings: W x L x D W x L (2W+2L) D WxLxD

F1 6 x 4’ x 4’ x 1’-0 96 96 96

F2 3 x 3’-6x3’-6x1’-0 37 42 37

F3 2 x 7’-6x7’-6x1’-6 113 90 170

F4 2 x 6’ x 8’ x 1’-8 96 97 161

Chimney Footing 1 x 10’ x 8’ x2’-0 80 72 160

-2 -4

Totals 14 Footings 420 390 624= Concrete 24 Cubic Yards

27

Footing Forms (14) =390 Square Feet

Hand Excavation Area = 420 Square Feet

Plan Sec.

L

DWStart the job by looking for a column footing schedule. Ifgiven, list the description and dimensions from the sched-

ule. Then turn to the fo oting plan a nd c ount the numb er ofthe foo tings . This ma kes s ure that yo u include a ll of thefootings a nd no t just the ones liste d in the sc hedule. Thislist s hould include a ll “b ox foo tings ” w hich, in your judg -ment, would have to be located and staked out separatelyfrom the wa ll footings . it is important to list the tota l numberof foo tings in the las t co lumn so that this information will becarried forward to the recapitulation sheet.



one set of quantities. The hand ex-cavation area once again is the exact

width of the footing times the lengthso that you can take the area andmultiply it by the depth to get thecubic yards of concrete re q u i re d .This is a time save r. The form s, of course, will be twice the depth timesthe length. The 2 by 4 keys are thetotal length of all wall footings.These four items: hand exc a va t i o n

area, contact form area, 2 by 4 keysin lineal feet and concrete in cubic

yards are extended into the last col-umn on the right and checked thus () for future extension again to yo u rrecap sheet for pricing.

The 2 by 4 keys are not re p l a c e-able, and cost about 8 cents per lin-eal foot plus labor for installationand removal after concrete has been

placed.The concrete quantity is always

the most important item that wetake off. On most items, such asform work, you can afford to be a lit-tle too high, but concrete quantitiesshould be obtained as accurately aspossible including an allowance for waste where re q u i red. I l ike to in-clude about 3 percent waste for con-crete placed on the ground. I do not

include waste, however, for concreteplaced in forms.

All estimating is truly guess-timating, but you should try to tied own precisely those items of costthat can be t ied d own. Co n c rete issuch an item. Depending on thespe c ifi c a tions, concrete will alwaysh a ve an exact cost and since thiscost will be about one-third to one-

quarter of your total concrete bid, itis worth tying down exactly. And by exactly I mean that when I take off c o n c re t e, if an item comes out 311/4 cubic feet. I call it 32, picking upp a rt of a cubic foot on each item.This is how I figure waste on the jobalthough I do add 3 percent addi-tional for all concrete placed onearth or fill.

Wall Foot ing

Square Feet Square Feet Cubic Feet EstimatedNo. Description Number Dimensions Area Forms Concrete Quantity Unit

2. Wall Footings: W x L x D W x L (2W+2L) D WxLxD

Line A - 1’-0 x 2’-0 x 56’ 112 112 112

Line B - 0’-10 x 1 ‘-8 x 48’ 80 80 67

Line C - 1’-0 x 3’-0 x 56’ 168 112 168

Line D - 1’-2 x3’-8 x48’ 176 112 206

+4 +4

Keys = 208 540 420 553 = Concrete 21 Cubic Yards

27 Forms = 420 Square Feet

Hand Excavation Area = 540 Square Feet

2 x 4 Keys x 208 Lineal Feet

Thes e exa mples a re for different types of w all footings . No spe cific b uilding is intende d. The w idth a nd d epth a re listed tothe closest inch and the length to the c lose st foot. The area is listed as the exac t co ncrete area to help in getting the c on-crete volume by multiplying the a rea b y the de pth. The c ubic ya rds o f co ncrete in the la st c olumn are liste d to the close stya rd a bo ve any fraction. The 2 by 4 keys a re liste d to the close st linea l foot. I pla ce an “ x” in front of the q uantity listing forthe keys be ca use this item is to b e kept sepa rate from the form items tha t w ill be ad ded up on reca p s heet for “strippingand cleaning” by labo rers. Chec k eac h item in the last c olumn as it is brought over from the ta keoff sheet.

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