I thought that design software enabled the architect/draftsman to automatically generate a lumber material list. Whenever I have received a set of plans there never is a material list. Am I incorrect in this assumption?
For bidding purposes, it would make more sense if every contractor bidding on a job was working off the same basic info.
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Replies
Whenever I have received a set of plans there never is a material list.
What makes you even think that you would get a set of plans with a lumber list? Who do you think is supposed to do it, the Architect?
For bidding purposes, it would make more sense if every contractor bidding on a job was working off the same basic info.
If it's so basic, how come you don't know how to do a lumber list? Also, if you're supplying the material, you would trust someone else's lumber list and use that list to bid materials? What happen's if they were short $5000?
So, who does you limber lists when they don't surprisingly come with a set of plans?
I know that design software comes with the ability to generate a lumber list. Yet there is this hesitancy to use that feature.
I have been generating my own lumber lists, an excrutiatingly painstacking task. My supplier also has someone they use that charges 16 cents a sq foot to generate a list for you. This averages out to about to 200-300 dollars per bid, and if I don't get the job that comes out of my pocket. If I get the job, the lumber yard picks up the tab.
I understand where you are coming from, although you might want to tone down the flame. It would just seem more logical if everyone ( all contractors bidding on a project) were starting from the same point.
The architect also would want to call out certain types of material, engineered lumber as opposed to regular lumber, etc.
The way the system works out now, the homeowner is comparing apples to oranges when looking at several different bids. The whole thing just seems so messy.
I know that design software comes with the ability to generate a lumber list. Yet there is this hesitancy to use that feature.
Since when is someone else supposed to figure out every contractors material lists?
I have been generating my own lumber lists, an excrutiatingly painstacking task.
How difficult and painful is it to do a lumber list???
The architect also would want to call out certain types of material, engineered lumber as opposed to regular lumber, etc.
Since when doesn't an Architect not spec all this out? It's on every single plan I've ever seen before. It's up to the contractor to figure the quantity and that's very easy.
BTW, I'm not flaming you. I just think you're making a big deal over doing a lumber list. If you think that the Architect should supply a lumber list so that every contractor is bidding on the same list, you might as well expect them to figure out materials lists for, block, siding, roofing, plumbing, electrical, insulation, sheetrock, trim.........etc, so that everyone is comparing apples to apples., Joe Carola
yojimbo2
You could build your own Excel program to figure materials.
I attached a simple example. By entering 3 numbers in yellow the excel sheet figured everything else. This is for a 20' x 30' house.
Add a contingency factor and you can protect yourself.
No program even if you write yourself is foolproof, but it gives you a leg up.
This is just a simple example I used wall LF x .75 for studs. In this example there is not provision for corners or headers. The second sheet has the formulas to the right of the cells.
Rich
Hey thanks for those spreadsheets. I will take some time and look them over. Very cool.
This thread would make a great topic for an article in FHB. How to bid on a remodel. Some of the things I have been fleshing out:
Distributing the plans to all the different subs. I have been faxing reduced copies to subs, but I imagine there are GC's out there sending plans via email. I have never seen a set of plans as an attachment, is it difficult to read?
What to charge as a GC on a remodel. I spoke to a couple of contacts and have heard something like 10-12% markup on each trade.
The lumber material list provided by the architect seems like a no-brainer to me, although a few posters seem adamantly against this sort of subversive activity.
It would be cool to see an article like this in FHB.
yojimbo2
We are a small remodleing /repair company in a rural area.
We don't deal with architects, and not too many plans.
If it is an addition or a basement remodel then I have to draw the plans up myself.
I mark up materials 20%. I was at 10% until this winter I decided i need to make more on that end of things.
If I have a sub then I would mark up their bill 10% or 20% if i was bidding the job. 10% if it was T&M and 20% if I was figuring the job for a bid or estimate. But we do most all our own work.
My wife always says figure what you think it will take and double it. She's pretty close sometimes.
I think on a spreadsheets. I have developed sheets for basements, roofing, additions, bathrooms, vinly siding, garages ect.
What i posted earlier is just an example of what you can do to make Excel do alot of the figuring for you.
100 LF of Ext. wall number can be used to figure, studs, plates, sheathing, insulation, housewrap, siding, drywall, baseboard. You just have to figure out the formula for each step of the operation.
The SF of the floor area can be used to do the floor system, ceiling, even the roof.
If you are doing it manualyl you are still using the same basic set of numbers just reinventing the wheel all the time.
You still have to check things and every job throws you a curve ball.
There was a good article in JLC in Oct. of 2006 on estimating with Excel by a guy who did it for lumberyards.
I can show you more stuff if you are interested.
You can manipulate the excel sheet on BT or you can copy and paste it on a blank Excel sheet for easier viewing.
Rich
"This thread would make a great topic for an article in FHB. How to bid on a remodel."
an article or a book.
and better make that a library of books.
either way ... it all ain't gonna be covered.
only way to learn is hands on and getting burned once or twice.
even then it's not an exact science.
reading about it ain't gonna help.
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
Jeff
only way to learn is hands on and getting burned once or twice.
Or 20, or 30 or when ever you get cocky and think I know it all.
Rich
Thanks for giving me credit on those worksheets but they aren't mine LOL! In MI, the lumberyards would do all the takeoffs, free. We'd drop off the plans and someone would give us a list. We'd then use that list to shop prices. It doesn't seem fair, but as long as you don't continuously use the same lumberyard to do the takeoff, then give the job away, they don't mind. Normally, we buy from the lumberyard that did the takeoff. It's a loyalty thing. The other guys are just keeping the price honest.Here in TX, the lumberyards want to be paid for takeoffs. They haven't figured out that they'd get a lot more business if they actually provided some service other than shipping the wrong amounts, wrong sizes and junky lumber....late.Anyways, Frank and I were peeved and one day I told him to find out what it costs per square foot for lumber from the builder salesguy. I told him if the builder salesguy can't give us a square foot price off the hip, then he obviously hasn't done enough work in the industry and we'd get another lumber salesman. So, Frank brings in the plans and demands a price. The guy starts the BS story about needing $75 and three days to do a take off and Frank cuts him short and says "if you can't give me a decent ballpark price on this plan in less than five minutes, we'll find another lumberyard to deal with....you obviously don't know enough about your industry to work well with us." The guy then comes back with "Oh...we will supply a "quick takeoff" at no charge. I'll get back to you with a price later today. Now think about this folks....they ship house after house after house and they know how much the lumber loads are. They know how much a 3000 sf house will frame for. Yes it might be a tad more if there are fifteen big microlams and it might be more if there is 3' overhangs and detailed dentil blocks and stacked cornice. But...if you bring in a typical 1500 sf ranch with a 6/12roof, it's going to be the same price that the other one was shipped earlier that day isn't it? Bob's next test date: 12/10/07
Jim
Now think about this folks....they ship house after house after house and they know how much the lumber loads are. They know how much a 3000 sf house will frame for.
As always you are right.
Here they will figure materials for you for free. And if you give them a week to get back to you.
But I am just small change. I never do new construction so I rarely ask them to do a materials list.
All the random little jobs that we do require me to do my own mat list.
It can take 3 days (or 30 minutes) for them to get back to me on price for a window or door.
Rich
....they ship house after house after house and they know how much the lumber loads are. They know how much a 3000 sf house will frame for
Well, you're right, but ...
There's what, six, seven yards in the metro Austin area? The biggest national (tract) builders sometime don't even use them. That leaves the yards working in the remaining 30-40% of the housing market. That's going to be two things down your way. Either very sharp, professional, builders who will have already nailed down a pretty precise BoM. And, then the rest, smaller outfits, HOs, and the like--so, as a guess, the yard employees (not a low-turnover job in our parts) may not see enough of the same sized buildings to ever get a feel for something that might seem to the rest of us a natural sort of comparision like-to-like.
Wander two hours in my direction and we have excatly two yards to work with. They might offer a take off, but I can't think of a person, including myself, who'd trust them to know much more than the cost of a 30-pack of keystone to any accuracy. The problem locally being not the batches of cookie-cutter plans being knocked out, but that there's about 15,16 builders turning them out at different times and rates.
The yards are not seeking out the best and brightest, either--or at least not as I can tell. Ad in the paper for a door assembler for the one yard--$7.50/hr Makes a person want to order up a bunch of their pre-hungs, don't it now?
Occupational hazard of my occupation not being around (sorry Bubba)
Those are nice spreadsheets Jim, even if you don't claim credit.
One question though for you or for anyone else: How is lumber used in the construction process accounted for? You know, the lumber used for temporary bracing, roof toeholds, scaffolding, temporary stairs, etc. For example, the siding guys ended up using 10 sheets of OSB to cover over the undecked deck so they could move their ladders around. Not much of course, but that taken with a lot of other small stuff seems to me can throw a BM off.
My situation isn't quite like that of you guys in a "for profit" endeavor. I'm on the verge of completing my own house acting as the GC. To set up the initial budget I had the lumber yard do a take off. I bumped their number up 10% just for contingincy purposes. Turns out they were pretty close but there was a lot of lumber (or so seemed to me) used for the stuff listed above that would effect the bottom line in a true business setting.
Thanks!
Runnerguy
Personally, I minimize the waste in every conceivable manner. So, of your list, I might "waste" $50 worth of lumber on a 2000 sf home. Most of my guys could easily waste $500 on the same job. Frank is a clean freak and throws away a lot more material on one job than I would waste on five so there is no set answer for your question. Then, the way framers frame can be a huge difference. I've been criticized for nailing two chunks of ten inch long scraps together to form a 14 1/2" fireblock. Some guys thinks that is crazy. I think it's crazy to throw them into the scrap pile. Those same guys think they need four studs on every corner. I can do the same corner with two or three. Bob's next test date: 12/10/07
"Personally, I minimize the waste in every conceivable manner."
You might want to head over to London to lend a hand. Their Olympic Aquatic Center for the 2012 games has snowballed from 75m pounds to 242m. That doesn't include an extra 61m for the land bridge that forms part of its roof.
I'll trim them wasteful buggers down. Thanks for the lead. I'll start rowing tomorrow. Bob's next test date: 12/10/07
runnerguy
How is lumber used in the construction process accounted for?
Simple.
Add a line for Waste. For the waste column i changed the formula in the top cell (Sill Plate) then used fill to change everything underneath that. Some waste is 5% some is 10% whatever you decide. Frank would need a higher waste factor than Jim.
Then add a rows for bracing, backing, window openings.
Then say the customer comes back and says DW wants a 30'x 40' house. What's that going to cost.
Just change 6-7 numbers and you can e-mail him back the new number. (Jim Allen #3).
I know in the real world it's not as simplistic as this, but I am trying to make a point of letting the spreadsheet do the grunt work.
Rich
I thought that design software enabled the architect/draftsman to automatically generate a lumber material list. Whenever I have received a set of plans there never is a material list. Am I incorrect in this assumption?
Some software do do just that, but you often have to go and recalculate to be sure of the "how" that calcuation was made--hard to find 2x8x11', even when on the list; Many of the BOM (Bill of Materials) lists are only as smart as the programmer, who may have even less framing experience than the drafter. So, that magic amount you need for blocking and bad sticks and the like is usually not in there.
Also, plans with material lists are more common from plan book outfits, or plan houses--in architecture you are supposed to leave material estimation firmly, by contract, fully within the perview of the contractor to estimate.
Which means, generally, plan sets with BOM, and written specs in he corner are least likely to have had any architect's input at all.
Telling comment in this month's FHB, that 80% of house plans have not come from, or near, and architect.
it's easy......
You take the plans to the lumber yard
sit down with your salesman (every builder should have a salesman)
show him the plans...tell him what you want and leave
he calls you later with a full workup and a price.
he takes responsibility for overage/underage ...checks the jobsite to make sure things are working out. etc.
"he takes responsibility for overage/underage ...checks the jobsite to make sure things are working out. etc."
who you talking about - the salesman?!
since when?
If I'm short a piece of sheathing, I never heard of a salesman sending of an extra piece on his dime. View Image View Image
Brown'Graves Lumber Company....Mike G. salesmanThis was standard operating procedure for ever till they and a lot of other old time customer based yards folded do to the emergence of "the big box" everyone seems to love.
wow..that would be impressive - never heard of that before.
Depending on the salesman, you never know how close the take off is going to be. The quotes always specify everything to be confirmed by contractor. Sometimes they are way off. View Image View Image
these guys were pro's......they understood everything about home building...did great take-offs...it was all a service for their contractors.Walk into the office with print in hand, grab a cup of coffee, sit down and bs for a while. Talk about all the particulars......get a phone call a few days later..........there is something to be said about the good old days.Last job I bid on (before I gave it all up) was to trim all units in a large apartment complex.....labor only. I lowballed my bid cause I needed work. They went with a group of Russian immigrants who actually cut my price by half.......and did a horrible job I heard later..........welcome to the exciting new world of home building.
thought that design software enabled the architect/draftsman to automatically generate a lumber material list.
Yeah, and 'SpelChek' enables peopel to spell things wrong and blaame it on the cumpooter. How'd you like to get a BM that was automatically generated, bid based on it, get the job, and then find out on getting halfway through the framing that the automatically-generated list missed, say, $3000 worth of stuff you now need to buy out of your own pocket?
Computers cannot think; they only execute excruciatingly precise instructions within strictly defined rules. Whether those instructions--and rules--apply to the real world in a sensible way depends on how well the person who wrote them understands that particular real world.
Programmers can think, but they are not builders, nor are they architects. Really top-level ACAD artists like CapnMac write their own LISP scripts, but they are rare. And it takes more than a short script to correct faulty assumptions in a program, which are the usual cause of a nice-sounding idea not working worth a hoot.
Make up your own BM. Nobody said it was as much fun as swinging a hammer, but it's part of the job.
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
My two cents on BMs. If all ceilings were at 8'-0", all floor joists 2x10@16"o/c, all ceiling joists 2x6's, all rafters 2x12, etc. some programs could generate lists.
However, however, that ain't going to happen. You do, of course, add 3 to 5% overage on your purchase for bad wood, unexpected framing requirements, etc?
Once a contractor has a system and knows his people and how efficient they are in using the materials then he can put together a reasonably close estimate. But there is always the "but factor". As in "I like the plan but I really wanted a different wall location for the......"
As an Architect I am asked to generate BMs but never had, and my response is always the same, "Too many variables, and I don't get paid to do your work, sorry." I'll run up a total of linear feet for the different unique wall types but that is it.
Let's see I used (***** number) letters and probably made no sense. At $#### an hour someone owes me...........
ciao, ted
If all ceilings were at 8'-0", all floor joists 2x10@16"o/c, all ceiling joists 2x6's, all rafters 2x12, etc. some programs could generate lists.
On the first house I ever designed and built, I added up all the materials & costs involved in building an 8-foot-long wall section, and then divided the total length of wall on my plans by eight and multiplied that number by the cost of each section. In theory, I told myself, that would give me a dollar figure for all the wall materials I needed to buy. I also 'took out' the number of 2x's and sheet good panels for each section and multiplied those numbers by the number of sections to get my BM. I did the same thing for the roof and floors (in square feet), then added everything together and went to the bank with it.
The bank manager bought it, and loaned me the money. Fortunately, I decided to order things from the lumberyard as I needed them, instead of giving them one big order from my BM.
I said fortunately, because I was about 30% low on my estimate. This was mainly because in my inexperience I had overlooked all sorts of 'little' things I'd need to actually finish the job. Like fasteners and tape and mud. The thousand bucks worth of insulated VB I realised later I would need to get a decent R factor in the cathedral ceilings. The rafter-vents, sill seal, and pitch. Joist hangers and H clips. Solder and flux. The paint and stain. Scaffolding rental. Bobcat rental. 18 truckloads of sand to backfill.
Good thing I had ten grand of additional credit available for 'emergencies'....
The bill of materials for only one phase of a project is simpler. If all you're doing is framing the place or roofing or siding it or roughing in the electric or plumbing, there's a lot less stuff to worry about. Remod guys or whole-house builders have to break down every unit by all the trades involved, and not miss anything. I don't know any computer program that can do that. Hell, I don't know very many builders who can do it. Everybody misses something.
I still miss things, but I've learned to use spreadsheet programs to take some of the grunt work out of things, and often checking the sheet from a similar job will remind me not to forget something. They're invaluable for moulding and trim calculations, for example, where there will often be 15 or 20 different mouldings in a complex job, a third of which I may wind up cutting myself. I use spreadsheets mostly for stuff like that, because in the average remod I don't have so much framing to do that I can't add it all up in my head easier. Or so I think, LOL....
Even so, 15 years after that first one, I still hate estimating, but I'm better at it. And now I charge for it, too. It's work, and like you said, I'm supposed to get paid for working. I can usually nail the cost of labour & materials to within 10-12%, even with the vagaries of remodeling. But it probably took me damn near 5 years to learn the most important lesson of all: That whatever I think it's gonna cost at first, DOUBLE IT. And then go looking again for what I've forgotten....
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
"I can usually nail the cost of labour & materials to within 10-12%, even with the vagaries of remodeling."
Bravo! You're better than most. Been ask what is the toughest kind of job to work on or design and remodeling is the winner hands down. A good part of it is not knowing what you may find when you open 'er up to tie into and working with the HO to help them understand that there may be field changes that have to be addressed (read: cost more). Any residential work is a very personal experience for the HO and some get really testy.
Anyhow, you and the other guys on this thread have opened my eyes to some of the difficulties that are faced on a daily basis. I'm going to try to improve (not that they need it, ;} ) my drawings to ensure a bit more clarity. Makes my clients happy because most expect change$ and will make my Contractors happy because they won't have to 'explain' why the cost just went up.
BTW, I stay with every job under construction until its finished and make it a point to act as a buffer between the C and the HO. Takes the strain out of the job and I and the HO, generally, get a better finished job.
ciao, ted
"I can usually nail the cost of labour & materials to within 10-12%, even with the vagaries of remodeling."
Bravo! You're better than most.
LOL. Note that the key word in that statement of mine is 'usually'....
Nobody gets it right all the time. When I started in this business, I didn't have a clue. But I thought the experienced guys had it all taped, and I beat the cräp out of myself everytime I went over estimate. Ate a lot of overage--without ever mentioning it to the HO, either--out of pride, and a fear that the HO would tell me to take a walk if I tried to bill him for what the condition of his house had cost me.
Over the years, I learned a few lessons:
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
I imagine that anyone who's been in business, any business, including the design professions(Architecture really is one!), has a story for each of the four points you made. I know I have.
Your first point has cost me plenty! LOL!
Your list shown be printed out and placed on the wall. To remind ourselves, as well as a memory jog, if we backslide on the points.
Well said.
ciao, ted
Your first point has cost me plenty! LOL!
Me too....
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Dino
I still miss things, but I've learned to use spreadsheet programs to take some of the grunt work out of things, and often checking the sheet from a similar job will remind me not to forget something.
Would you be willing to share one your spreadsheets with us?
I would love to see how a sheet takes the grunt work out of it. I would love to learn from your experience.
Rich
Would you be willing to share one your spreadsheets with us?
Here's one I use for the moulding buy. There's two ways to do this:
One, you can take the measures off the plans and plug 'em into the spreadsheet; or two, you can print out a blank copy of this and then run through the project once the 'rock is up with a measuring tape and a pencil, and write 'em all down in the appropriate boxes. Then go back to the office and type it in on the computer (or, if you're really modern, do it directly onto your laptop on-site).
The formulæ embedded in the spreadsheet do the calculations for you, and then all you've got to do is take it to the yard and spend a couple of hours sorting through the bins looking for decent quality sticks of moulding....
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Dino
I couldn't open this file.
It looks like a Works program, maybe newer than I have.
About 2 years ago I started doing everything in Excel.
I am not sure I want to download software to open it. I've got enough stuff on this PC.
Thanks anyways.
Rich
Here's the same document as an .xls file, which according to my computer is good for Excel 97-2000. Apparently it's backwards compatible with 4.0 and 5.0 (? whadda I no ? )....
EDIT: Ooops. Sorry. I thought I'd managed to re-save the original document as an xls file, and uploaded that to BT. But it turns out all this machine actually 'saved' was an import command, not a document. I'm apparently not equipped to save documents as .xls files, only to open them.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Edited 4/28/2008 9:36 pm ET by Dinosaur
Dino
Well, I'll give you credit for trying.
Rich
Rich,I just manually changed the .xlr extension to .xls and opened the file with Excel. You might give that a try.Dan
Dan
Well I'll be. That worked.
I never would have thought of it.
Thanks
Rich
Dino
Nice speadsheet. That would help alot keeping track of stuff in the field and when it comes time to order.
I made some changes to it and then reposted.
I used roundup on the columns for 7 and 8' lengths of trim. So it will automatically round up to the next number, because that is how you would have to buy it.
I also added color to help keep things straight visually.
But it is in excel now.
Rich
Nice job. The colours do make it easier to see on the screen, but in that my ancient Windows 95 Laptop can't talk to this box, I don't bother taking it with me, so I have to print those out. I think I'd stick to alternating bands of white/20% grey for the hard copy. That helps the unaided eye track laterally across the width of a 14"x8½" page. (Also saves $$ on that hexpensive coloured ink cartridge....)
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
I've never had anyone else do my material lists for me. Sometimes I wish I did because I wouldn't be carrying 100 extra studs from an 900 SF basement (hey, that was several years ago) but that's neither here nor there.
My question is- What happens if the list is wrong. If you bid a job with an $8k lumber package, do you eat it if they're $500 under? I'm doubting the yard sends out any extra lumber fore free with a note asking for forgiveness.
Jon Blakemore
RappahannockINC.com Fredericksburg, VA
I dealt with an old school reputable lumber yard who had sales people (usually the same person) who took the plans and made the material estimate......they always sent out extra and took back what wasn't used.Mike (my salesman) showed up at the job site about once a week to see if I needed anything, or I could call anytime if I needed extra studs etc. they were delivered ASAP free of charge.....Now in todays world where you deal with Big Box ninnies I would make my own material list also cause I don't trust them...... things have changed.
The extra 100 studs are picked up for credit.Okay, lets say you order a house package and it's 8k but should have been 8.5k. Let say the house was 1200 sf on a slab. Wouldn't you know that a 1200 sf house on a slab is 8.5k? Bob's next test date: 12/10/07
I'm afraid I don't know what you're saying.Wouldn't who know that a 1,200 SF house is $8.5k?BTW- $500 on an $8k package is 1/16 or 6.25%. That's not a lot of wiggle room. If one 1,200 SF plan had two closets and one had a four closets and a few bumpouts and niches then you could easily be 6.25% off.My struggle with estimating is that a common variance is equal to the profit margin goal. Dinosaur just said he has taken years to get within 10-12%. I would love to have a 40% net profit margin, but that's just not realistic. If "good" is within 10% and the net profit margin goal is 10%, that makes me nervous.
Jon Blakemore RappahannockINC.com Fredericksburg, VA
I wouldn't be carrying 100 extra studs from an 900 SF basement
Got that one beat.
Once ordered 45 extra sheets of SR for a basement. Basement access was up the big hill, on the far side of the house.
Guy's were less then pleased....
Turns out I may have accidently doubled a few numbers while making the list....
some reason it didn't sound as far off when I placed the order as it did when I looked at it later.
I that something like ordering 12 extra squares of soffit material on a house?
Jon Blakemore RappahannockINC.com Fredericksburg, VA
I think the degree of the screw up is directly proportionate to the items weight and the distance it must be moved lol
I think you're right.Fortunately, I haven't ordered five extra yards of concrete yet.Yet.
Jon Blakemore RappahannockINC.com Fredericksburg, VA
Jon
Fortunately, I haven't ordered five extra yards of concrete yet.
I have.
Out of college I worked for a carpenter for 6 months. Then worked at a shoe store (25 years ago) for a couple of years. During that period I put a small addition on the house.
1/2" plywood sides of the forms that bowed.
I don't remember how much concrete extra I ordered, but it was 3-5 yrds extra. We lived in the country so we just paved part of the driveway without forms. 2x4 screeded it and walked away from it.
It's funny now, but I was doing the pour by myself and I was lucky enough to have a driver who would help me run the screed.
Now I tell the ready mix the size of the pour and let them figure out how much to bring, even though I know now how to figure it.
Rich