Any builders/framers here care to comment?

[lendaddy]

I've been trying to find industry standards/norms regarding bearing wall elevation tolerances. In other words, how similar should you expect the elevation of the top plates on the concrete walls (as well as the top plates on any bearing stud walls) to be?

I'm not referring to the pour of the foundation walls, rather the carpentry work of leveling the top plates on those poured walls(if required) and constructing equal height bearing stud-walls. Effectively the surfaces that the floor joists will rest upon.

I've found sub-floor flatness/slope standards in the Residential Construction Performance Guidelines (which are certainly directly related) but I can't find anything along the lines of: "All top plates, forming the basis for the sub-floor, should be within 1/2" of the highest point over any 20' radius." or "abutting top plates should have a transition height differential of no more than 1/4"." And the examples above are pulled out of thin air, pay them no attention.

That type of thing

I'm interested in both professional opinions and industry accepted standards/code. I honestly don't know if I'm being overly critical. I'll share my numbers later but don't want to shade responses up front.

Thanks guys!

[cabmandone]

If the concrete is poured correctly it's just plug and play. Assuming they installed the J bolts in the concrete you just put the bottom plate down and install the nuts. I have built several garages and never worried about the plate to wall fit. I just put the plate down, framed the walls, stood the walls on the plates and fastened the wall to the plate with nails at each stud. Never had any issues.

[1990C4S]

I would expect +/- 1/4", or 0.5" max deviation.

Ideally it would be within 1/8".

At 1/2" you have to shim and fix it, which would piss me off. A lot.

[lendaddy]

Agreed, most I've spoken with say adjustment isn't usually required and that concrete teams are quite good these days. My question is only in the event it is required and perhaps more commonly the height of the top plates on stud built bearing walls as is common in walkout basements or homes built on elevation changes. My home for instance has three different poured heights to the outer foundation walls. The difference is made up by a stud built bearing wall on top of that partial foundation. I'm interested in how well those ultimate heights should line up.

[lendaddy]

Originally Posted by 1990C4S

I would expect +/- 1/4", or 0.5" max deviation.

Ideally it would be within 1/8".

At 1/2" you have to shim and fix it, which would piss me off. A lot.

Thanks much, can I ask if you have a background in the industry? Appreciate the information either way, sincerely.

[javadog]

It’s really up to you, how crooked do you want your house? In this day and age, it’s not hard to work to pretty small tolerances, like a 16th or an 8th.

[lendaddy]

Originally Posted by javadog

It’s really up to you, how crooked do you want your house? In this day and age, it’s not hard to work to pretty small tolerances, like a 16th or an 8th.

Not crooked at all thanks, but this is done. The question now is what can be done if we agree it's not acceptable.

[javadog]

Well, you can make the walls from different stud lengths to get to where the top of the wall is at the correct height. You can plane the bottom plate a little bit on jointer to reduce the thickness, if that’s appropriate. You can shim the bottom plate. Etc.

It all depends on how far off things are.

[cabmandone]

If you're worried, tack a string line from end to end and check for variance. If they used a laser and grade stakes to set the footer, you might be concerned with a non issue. What are we building?

[cabmandone]

Reason I ask what is being built, if it's a home and you're using conventional lumber rather than manufactured joists and laminated beams for the end caps, the 2x12 used for the flooring and the box sills can have "crown" that would be outside 1/4 variance.

[lendaddy]

Originally Posted by javadog

Well, you can make the walls from different stud lengths to get to where the top of the wall is at the correct height. You can plane the bottom plate a little bit on jointer to reduce the thickness, if that’s appropriate. You can shim the bottom plate. Etc.

It all depends on how far off things are.

Agreed, many things could have been done to make them essentially perfect and fewer things can be done to correct after the home is built. Right now I'm trying to determine if what I'm seeing is within industry norms or not. If norms aren't established then I am interested in establishing a near consensus spec that is outrageous.

[lendaddy]

Originally Posted by cabmando

If you're worried, tack a string line from end to end and check for variance. If they used a laser and grade stakes to set the footer, you might be concerned with a non issue. What are we building?

This is my new home; single family ranch layout. The joists are engineered I-Joists (16" on center) with rimboard all around, 23/32nds subfloor.


Edit: I intended to add that I have shot it with a laser and know where it is but I'm meeting with my builder in 90minutes after I asked him to measure/evaluate if it's up to his standards.

[URY914]

I doubt if you'll find a standard tolerance for this anywhere. It's not a structural requirement as it is a elevation issue. Vertical challenges are made up in the height of the framed walls. If your talking floor joist bearing heights, joints are shimmed to level the floor.

[javadog]

Dimensional variations such as this are either laid out on the plans or in the specifications. I don’t know that there’s an industry standard, or even a code requirement. My background is in commercial construction and those projects are pretty well documented. Your house project probably is not, so you may have an interesting discussion with your builder.

[look 171]

How far off is it? conventional lumber will shrink so there's go the 1/4" but it really depends on a lot of things. How long is the run on this wall? 1/4" at 50' is acceptable to me and I am a pain in the ass perfectionist. The guys I use know me and they know i will btich so its easier that they do it right the first time

[1990C4S]

Originally Posted by lendaddy

Thanks much, can I ask if you have a background in the industry? Appreciate the information either way, sincerely.

Educated engineer. Not a house builder by trade.

I meant to add a) I am not an expert and b) I will defer to the builders.

[CurtEgerer]

The Residential Construction Performance Guidelines are not a mandatory standard, unless agreed to before the project starts. They are generally biased toward the builder (the tolerances are at the outer range of acceptability), since home builders wrote the standard in an attempt to resolve the exact type of issues you're dealing with. I have used some of the RCPG 'standards' in Expert Testimony over the years, basically because in most cases there isn't anything else! The building code (IBC) only addresses tolerance issues in a general way via workmanship provisions but does not spell out dimensional tolerances - unless it has some sort of adverse affect on the load carrying capability of the structure. So the building inspector will not have authority to force changes unless he referred the matter to a P.E. such as myself to basically declare the construction is - or is not - acceptable.

Your best bet is to look to the I-joist and subfloor (and/or flooring - particularly tile) manufacturer's requirements and see what their flatness requirements are. This is ultimately a fuzzy gray workmanship issue and it is up to you and the builder to resolve it, or hire an Expert and let the Court do it for you if you have a few years to waste. Ahh, the joys of building a new home

Did I tell you I hate I-joists?

[lendaddy]

Originally Posted by URY914

If your talking floor joist bearing heights, joints are shimmed to level the floor.

I would argue in this case perhaps "should have been" more than "are".

[lendaddy]

Originally Posted by javadog

Dimensional variations such as this are either laid out on the plans or in the specifications. I don’t know that there’s an industry standard, or even a code requirement. My background is in commercial construction and those projects are pretty well documented. Your house project probably is not, so you may have an interesting discussion with your builder.

True enough, I know there aren't any specs but there are standards for floor conditions (which is what started this). This I believe is the root cause of that issue so I'm just trying to do some diligence.

[javadog]

It sounds like you need to stop your builder where he is and not allow him to continue until he corrects these issues to your satisfaction.

I’m not aware of the specific issues, obviously, but from your description it sounds like they would be something I would not tolerate.