Wood Flooring Yield and Waste Factor
How much rough lumber should I order for milling into a given quantity of tongue and groove wood flooring? June 8, 2011
Question
If I'm going to need 3000 sq.ft of flooring, how many board feet of 4/4, #1Common should I order of red oak? I have a local guy that says he does "2 for 1". He orders 6,000 BF, if he's after 3,000 SQFT of final flooring. It seems excessive. Assume I'm after all the final flooring boards to be 3" width with a 1/4 tongue.
Forum Responses
(Sawing and Drying Forum)
From contributor M:
The two for one estimate will probably be pretty close if you are ordering r/w/l #1 Com red oak to make all 3" face (3-1/4 overall). There will be some that is too narrow and you will get a terrible rip yield on 5-7". Much better yield if you have other rip sizes. Can you make the order 2-1/2, 3,and 4 as it develops?
Another option to consider is buy #1C selected for width or buy ripped blanks at a fixed price per lin ft. Depending on the flooring grade you are producing you may need to figure 15-20% additional waste to trim, defect, and reject material. Also check the price on selects and 1 x 4 selects. Higher price per bd ft but improved yield, longer lengths and fewer defects may even out, and you will have less footage to run through your operation to make the sq ft coverage.
From Gene Wengert, forum technical advisor:
Is the footage a green footage? If so, it will shrink about 6% for northern and 19% for southern when dried. Or did the supplier measure the dry footage and then add back 9% or so? (This latter practice is not legal).
Most flooring mills use No.2 Common and No.3A for flooring. They get about 50% yield. Higher grades give high yields, but the cost of the higher grade (like 70% higher) is not accompanied by a 70% increase in yield, so high races are not used - yield increase is only 25%.
The biggest loss in yield is when you use a piece of lumber 7-1/2" wide and cut 2-1/2" wide blanks with a 3/16" saw blade, so you only get two flooring pieces from this 7-1/2" piece or about 67% blank yield compared to over 90% yield from an 8" wide piece of lumber. You need to find a use for narrow pieces (narrow flooring or kiln or sticks) to boost yields and profits and reduce waste of our resource.
From Gene Wengert, forum technical advisor:
Correction - south shrinks 10%.
From the original questioner:
Here's some more info. My supplier of lumber is willing to pull for width, if I pay 20% more. I do have a demand for 1" dowels and 3/4" dowels of red oak. This is all kiln dry lumber. The difference between #1common and FAS/Sel is a nickel per BF from my supplier. Armed with that additional info, what do you all think?
From Gene Wengert, forum technical advisor:
The yield of clear two sides from No.1 will be nearly identical as the yield from Select. This is because Select is the same quality as No.1 common on the poorer side. With clear one side pieces the two grades will have around 15% yield difference. Can you get No.2 common at a lower price? The yield may drop 7% for 2 common, but the price can drop 50%.
From the original questioner:
My cost for FAS/Sel is $1.45/bf. #1Common: $1.40. 2A: 90 cents.
Surfing around the web, I'm seeing most flooring guys are calculating 30 to 40% waste. As I said earlier, my local guy figures 100% waste. Who's accurate?
From contributor R:
I recently did about 800 bd/ft of flooring with mill run (everything off the log from #3 to FAS) and was in the 50-60% range on waste. It started with about 1200 bd ft. This was from purely rough stock that was planed, straightlined, gang-ripped, and shaped to 2 3/4" reveal boards.
From Gene Wengert, forum technical advisor:
A typical yield for No.2 Common will run about 50%. 1000bf of rough KD lumber will yield 500 bf of flooring. Yields will be higher when multiple flooring widths are used, short flooring lengths are ok and lumber grades are higher. Yields will be lower when green footage is used or when only 100% clear flooring is made. Flooring has different grades depending on acceptable defects.
From the original questioner:
Would you say if filling a flooring order for #1Common grade, I'd be safe with a 40 - 50% waste factor, and if a customer requests clear flooring, and I start with FAS/Sel, I'd be safe figuring about 30% waste? Am I interpreting your information right? Assume also, that I have no further use beyond the flooring, for the lumber. Any additional use I come up with like 1/2" or 3/4" dowels, is just frosting on the cake.
From Gene Wengert, forum technical advisor:
In general, that seems like a good estimate, but yields depend on many factors, already listed, as well as minimum lengths, width of strips, flooring machine allowance, and so on.
