Grading lumber for an addition
Do you have a drawing of your addition to show your building inspector? He might want certain pieces bigger than normal if it's made out of a weaker type. Start with the man who will be the final inspector to get your plans and needs figured out.
The inspector will not want to put the responsibility of the grade of the lumber onto the county he represents, so he will no doubt tell you yes--you must get it graded. They will tell you right up front that, because you're milling the lumber yourself, it must be cut bigger than say 1 5/8 x 5 5/8 for 2x6. There's no reason for this and it wastes wood. If the grader says it's good right off the mill, then it should be good for the inspector. The grader is the expert.
I milled a garage-worth of lumber for a friend. He built the whole structure, had the siding on and the roof decking down before the next inspection. When the inspector got there, he asked if the lumber was milled at home and my friend told him yes. Nothing more was said. Of course, my friend used common sense with the lumber. Using a 2x6 with a 5 inch knot in it is not good building practice. The inspector passed everything. My friend planned on bringing a lumber grader out to the site if the inspector was not happy. He figured it would even be easier to grade all separated and in full view.
If you ask, they will say no. They will not accept the responsibility.
Here in Massachusetts, not all town-building inspectors say ďyes, it has to be inspectedĒ. Iíve sawn barns, garages and parts for houses out of native lumber. In one town, the building inspector wanted all carrying timbers such as headers 25% larger, because it was native lumber, not kiln dried. In another town, he wanted 15% larger. In another town he wanted 10% larger. In another town he wouldnít allow native lumber for any framing parts. So my customer had me cut it for sheathing. In another town he didnít care if it was larger and/or graded. Every town is different, and you canít assume that they all will say yes. Iím not sure how your state handles building inspections, but planning first and doing correct research to comply with all regulations would be the best choice, in my opinion.
Iíve also been to two grading short courses where the traveling grading inspector told a story of inspecting a standing building and finding defective timbers. The builder had to dismantle this building and replace these timbers, because the building inspector said he had to. Giving advice to build first is very risky. The fee for having your lumber inspected first is a lot less than dismantling a building to replace defective lumber.
In each town the lumber had to be different sizes? That means he thinks the lumber is different strengths in every location. This is true to some degree, but the codes cover all lumber in all regions, so a 2x6 from here is used the same as a 2x6 from there (assuming it's the same species). If that wasn't true, every single board would be stamped different according to its origin.
I doubt that any inspector is going to take the responsibility for your lumber being sound and suitable for building. He will say "ask someone who knows".
About removing bad timber: I'm assuming that the builder has the knowledge and common sense to recognize bad lumber before it gets nailed up. If he doesn't, he should get it graded. I had to saw my 2x4 for interior walls a full 2 inches thick, but 3 5/8 wide to use side by side with lumber-store lumber to make the inspector happy. The grade on mine was far superior to the other lumber. It was a waste.
If your state subscribes to the Uniform Building Code (UBC), there is a statement that goes..."or equivalent." So, I encourage you to ask you building inspector and then ask what you can do to make it equivalent. Understand that the grading rules exist for three reasons--to establish a fair price, to establish a reasonable strength (safety issues), and to establish uniform quality (commodity market). It is the safety issue that is of concern to the building inspectors.
One other check to make--can you get insurance for your house if it doesn't have graded lumber? Homeowner's insurance, but what if you sell the house and the buyer wants a Homeowner's Warranty? (Someday you will sell the house or your heirs will.)
You can get a professional grader to come in and grade your lumber, but he cannot stamp it, as the stamp is reserved for the company that owns the stamp, etc. So, you have a professional grader come in for a few hours to indicate that you have the "equivalent."
Gene Wengert, forum technical advisor
I spoke to my local building inspector about my project. His comment was "I think anyone sawing out his own lumber for a house is most likely going to use the best he has, and it will be far better than what we can buy around here." No grading required. I might add we are in a rural area, and probably do things different than in an urban area. The best advice I can give is to talk to the inspector first. If he has a tendency to be a horse's behind, at least you will know it before the project begins and can plan accordingly.
The statement that "you cannot have your lumber stamped" is incorrect. There are graders who can and do stamp lumber for hire. Not all of the stamps in existence are the property of a mill. (You may have to hunt to find them, though.)
Insurance companies usually specify that a home must be code compliant. The codes (in my area) say nothing about grade stamping, only that the lumber may be unsurfaced, s1s, s2s, or s4s, and meet the minimum strength.
I was in the local mega store the other day and saw a solid juvenile fiber, very knotty, unsound and waney 2x4 with a "#2" stamp on it. I am certain I can build a home with better lumber than that.
The building codes are there to prevent stupidity, laziness, and common errors from causing tragedy. Not to provide a monopoly to corporate mills for the production of construction lumber.
You can have your lumber inspected and grade stamped. Here in NC I contacted the Southern Pine Inspection Bureau (SPIB) and they have access to graders who will, for a fee, come and inspect all your lumber and grade stamp it. Up to about 20,000 feet a day.
You can use rough lumber, providing it meets your local building code. Your building code may require your lumber to "meet or exceed" a specific grade, which in turn may have a set maximum moisture level. Different lumber applications have different requirements, ie "Stud" Grade, #2 SYP, depending on studs or joists.
There are books that will help you select the proper timber sizes based on span and floor loading, based on size and species.
Local building inspectors don't often deal with rough-cut lumber and are therefore at a disadvantage. If you surprise them with it you can expect problems. If you plan, review, and coordinate with your inspector, you shouldn't have any problems. You can often find a copy of your building code at a good library or at the office of the inspector. If you are properly informed with the facts and present yourself in a positive and unobtrusive manner, there is no reason to not pass inspection.
Don't fool yourself on grade lumber and rough-cut. Grade doesn't have much to do with whether a piece of lumber is finished or not. It has to do with the size, placement, and quality of knots; limits on wane and MC in many cases.
I was referring to the fact that planed lumber is a visual confirmation that the board has met minimum size requirements (if you see a rough surface on a planed board, that board is too thin). This applies to framing lumber, not cabinet stock. This is why one inspector had me cut a full 2 inches thick--he didn't have faith that rough-sawn lumber can be consistent in size, and without planing them he had no way of confirming this. I understand this and cut my 2x6's 1 5/8 x 5 5/8. When they dry, they are over or at the minimum 1.5 x 5.5. Bottom line is, we don't plane framing lumber just to give it a smooth surface, it's just a way to size the lumber.
I recall reading about modulas of elasticity, in short, different strengths for different species = sizes, spans for given species.
I planed my boards to size, using high-quality boards, and threw around some tails of cut-offs from some bought lumber. Might be nice to have a few cheap store-bought studs lying around. Assume it's fine, take pride in your work, and get that mill out of sight!
The typical inspector in my area is reading from a book and his interpretation is literal, and doesn't include the word "equivalent". If his book did say "equivalent", he wouldn't know what the equivalent was to be. This puts him in the job of inspecting ink, not materials. When an inspector recognizes "other-than-big-mill-wood", nothing is going to satisfy him until he sees ink on it. Many don't even know what the stamp is telling them. To many, rough wood means unfinished, as in "you didn't get through processing it, so it's not ready to use yet".
It's really frustrating when you laminate two 2x12's together for a joist or header to feel better about what you are building and the inspector says "take it down, the plans call for a 2x10". Or you are in possession of 10m ft of flawless 2x12's and are required to find and pay someone to put ink on them so that the inspector will allow you to use them.
I'm planning to do some inspected building with my milled lumber. I will build and probably wait for the inspector to say something. Since here in California we over-size stuff just to meet insulation requirements, and we have to use earthquake plywood sheeting, I should be in good shape. I find that most inspectors are pretty fair if you stay on their good side. If the wood is clean, straight and free of major defect, I don't suspect a problem.
It was stated above that it would be fairly easy for a grader to see the boards and stamp them in place as need be. I understand that the biggest problem with grading is moving the lumber around quick enough to make the grading expedient enough. Someone said 20k board feet a day? Seems that would only be possible if it was on conveyors or some other fast-moving system. Homeowner's insurance? Warranty? Once the walls are covered, how does anybody know it is ungraded lumber? Be nice to your inspectors and make them feel important (cause they are).
I see ads in trade magazines for mechanical lumber graders for softwoods. These machines deflect each board and reject the ones that deflect too much. No grader to fight with!
Gene, the traveling grade inspector I referred to, who came to my yard and inspected lumber here, was from the NeLMA organization. They are the stamp issuers in my area. They do on-site inspections with grade stamps.
It is true that most stamps are at mills and cannot leave the business property. That's why they told me as well as a room of 50 other portable sawmill owners: "we will never issue you a grade stamp for your mills." Only the issuing association can make traveling inspections, to my understanding, but previous posts have shown me to be wrong.
An inspector came here and looked at the timbers I had for a timber frame barn, then stamped the ends of the timbers with a hammer stamp, no ink involved. All these timbers were then shipped to the site and the timber framer cut all the ends off and threw them into the burn pile, in the process of doing all the joinery necessary to build the barn. Not one timber that I saw on raising day had a stamp on it, (but the burn pile was full of them).
This builder told me that only when part of the building was going to be enclosed was it necessary to have the building inspector inspect the building before it WAS enclosed. As this was a timber frame barn and none of the insides will be enclosed, he never called for an inspection.
I never did understand why this building inspector wanted these timbers inspected, but he did, and we did it to satisfy him.
As to inspecting large volumes of lumber on a per day basis, the inspector who came here said amounts like that mentioned before can be done on a daily basis. With a good yard and forklift, you can lay out and inspect a lot of lumber in a day's time. It goes real fast. Sorting the rejects out after the inspector leaves is what takes some time.
As to using the best stuff for your own projects, we all would like to do that, and we should. You need to do some research as to the codes in your area, and be prepared to pay for whatever your decision is--an inspector now if necessary, or the dismantling of your addition if you build first and ask questions later.
In place of "grade stamped" lumber, they can issue you a certificate showing that the lumber was graded. That was from a SPIB certified inspector, though.
They would certify me to grade stamp lumber, but then all of the lumber cut at the mill had to be reported and therefore subject to being "taxed" (for lack of better words) by SPIB. There is a fee for using the stamp by the bd ft, as I recall, and all the lumber cut at a certified mill had to be reported and appropriate fees paid.
Needless to say, I don't have a stamp.
I was incorrect. You can contract with the major grading agencies to do a one-shot inspection and grading. It is quite expensive--you might be able to get some of those cheap studs at the lumberyard for less money than making your own!
I wonder if you can take your structural wood to a mill and have them run it through their planing mill--plane, grade, and stamp it. Anyone ever tried that?
Gene Wengert, forum technical advisor
That's what happens around here. We have a mill in a neighboring town owned by the son of the son of the man who started it and his grading stamp was "grandfathered" to him after his grading techniques were inspected. Also, the stamp cost him something like $300+ per month. When I send my customers to him to have their wood dressed (he has a 4 sided 12" planer/moulder), he grades the output of the dressing job as an inclusion of the fee.
His fee for grading on-site is expensive because, I think, he doesn't want to do it.
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