Acceptable...

Its called wain (where the bark was before milling) and is typically not anything to be concerned about.

The wood that looks “chewed” is the outer pieces of the log, the bark or skin.

It is a lower grade/less expensive and is used when hidden.

Your builder is either having sourcing problems or is pinching pennies.

You should find a grade stamp on each piece of framing lumber. The amount of wane on the studs has been judged to be permissible within that grade. If your architect or designer specified a particular grade of framing lumber you can compare their specification with what your builder has installed.

Not an issue. It's typical.

What you do want to do is call the builder and ask them to go through the structure with you. Upon occasion, one of these wains will be deficient. The builder will install a metal plate on the stud piece of lumber that will give it additional strength. It's worth while to go through the structure together to determine if any of these boards need the additional strengthening.

Thank you sir @User for sharing your experience. Yeah... I think the builder want to save as much as they can. So they use cheap materials and labor all the time. I feel almost 1/3 of the studs they used for the first-floor framer should be the one you are referring to (wane), and it looks really sloppy and rough. What makes me even feel more unacceptable is that after I walked through my neighbor's home, I found none of their houses having this issue - all the studs in their house are in good condition and look pretty new. :(

@homechef59 Thank you so much for your reply! :) And thank you for the suggestion. Yeah, I would definitely shoot them an email and schedule for an on-site walkthrough with their PM. Hopefully they could do something to ease our minds!

A truck load of wood is delivered to a job site, first come first served. While acceptable, some of your wood is a lower grade.....Some builders reject that wood...it may be a sourcing issue....use it or stop work.

Part of a learning process, due diligence, best wishes.

Thank you for the suggestion @Charles Ross Homes! Actually what we build is a new construction home (not a custom home) in a community. I'm sorry for the confusion. I don't have any specification sheet from the designer/architect/builder about what material they are going to use for the house. Our contract with the builder also doesn't list what grade of lumber they will be use for the framing. I guess their goal is to meet the minimal code of the city. But thank you anyway for the suggestion. :) I would try to find those stamps on my studs and my neighbor's so that I can compare if they are the same. Hopefully my builder could do something like adding the sister studs to make it looks more "reliable"...

That's the outer edge of the tree with bark showing (called "wane" in lumber lingo). Not necessarily an issue. Can you see a grade stamp on the framing like so: That would indicate if it was given an ok at the mill.

I'm guessing the grade is a no. 2 or no. 3 and is adequate for the intended purpose. I don't think you need to worry about it and I don't think you have any option anyway.

My brother is a contractor, one Thanksgiving week, I worked/helped him.

A truck load of lumber was delivered to the job site. This load of lumber contained 2-3 grades of lumber. The workers culled the lower grades of lumber, setting them aside. While the lumber was acceptable from a construction basis, he rejected it.

My brother’s contract with the lumber yard allowed for returns, he paid more for that option. Sometimes, the supplier has what he has.

Wood is delivered to the lumberyard from the mill.....the higher the grade, the higher the cost.

@Charles Ross Homes Thank you again sir. :) From your experience, do you think it will be an issue if almost 1/3 of the studs on the first floor are like that (1/3 missing structure)? We may want our builder to put some sister studs near those studs as makeup for the missing parts.

Thank you @User for sharing your experience! :) - learned a lot! Your brother is definitely a reliable and trusted contractor. He really cares for his customer and the construction quality not only trying to meet the minimal city code... Thank you again for all the comments, you have a good rest of the day!

Thank you @Seabornman :). I can find it in one of my photos. It shows A.F.P.A 161, S-P-F, NLGA, KD-HT STUD 2. (most of the studs don't have such stamps, while some others have) And on my neighbor's studs (all the studs in their house are in good condition and look pretty new), almost all of the studs have multiple stamps on each stud. And it shows a totally different stamp. I'll stop by to take a photo for my neighbor's stamp, so I can search online to find if they are with the same grade.

I feel almost 1/3 of the studs they used for the first-floor framer should be the one you are referring to (wane), and it looks really sloppy and rough. What makes me even feel more unacceptable is that after I walked through my neighbor's home, I found none of their houses having this issue - all the studs in their house are in good condition and look pretty new. :(

You can blame the COVID pandemic.

It has caused serious supply issues and the lumber yards/mills are desperately trying to catch up with demand. As a result, they've "relaxed" the standards for this type of rough framing lumber, allowing more 'wane'.

I helped my father pick up lumber for a small deck this summer. We had to pick through an entire pallet of brand new lumber in order to find a dozen decent looking pieces.

The grade stamp indicates "stud" grade which is perfectly acceptable for wall framing. It appears that the studs are pretty straight without twisting, warping, etc. Nothing to worry about in my opinion based on the photos you provided.

I agree. It all looks pretty good in the photos.

The amount of wood lost due to wane is way less than that permitted to be removed by holes drilled through the wood for pipes etc. Not pretty, but immaterial. What you may not see are all the pieces returned or put aside due to unacceptable warps that were missed during grading.

BTW, normally any delivery of framing lumber doesn't include several grades of lumber that the customer then picks through. What often happens is that un-dried lumber warps on the route from mill to wholesaler, to yard to the customer. Not even considering the big box lumber stored indoors (!) which no one but amateurs and handymen use--in this part of the world at least.

Looks totally fine and normal. So long as 1 side supports a square edge those studs are perfectly fine and usable.