I am trying to build a wall around a drainage pipe that goes along half the length of a wall close to the ceiling. I would not like to waste all the space by moving the wall in by 6 or 7 inches to avoid the pipe.

I was trying to figure out how I could work around it without having to lose much space. Should I move the pipe into the room to build a soffit around it or should I attach a treated 2x4 to the concrete wall and then use that to attach one side of the soffit and then build the wall underneath the pipe touching the bottom of the soffit?

Is that allowable from a New jersey code perspective? Does attaching a 2x4 to the concrete wall pose any structural disadvantages that I need to consider? Are there other options?

I do not know Jersey building code.

I do know that here in California in the few basements and cellars that are out here, attaching wood to concrete/brick/cinder block requires a moisture barrier and has to meet tectonic codes in the way of fasteners.

Our cellars/basements are not as well sealed against ground water as back east. Wood must be pressure treated and must have a rubberized gasket between mason and wood (or steel)

If an above ground masonry wall, attaching wood to it must be pretreated lumber (no gasket required) or steel with a gasket barrier between the masonry wall and the steel. Attachments also have to be bolts set in epoxy in drilled holes in the masonry - not just plastic molly bolts impacted in holes. That has much more to due with earthquake code than anything else for epoxy. Gasket is to prevent condensation and seepage/wicking of water to rust out the steel. I assume that the code works under the assumption that wood will dry out faster upstairs than downstairs or perhaps the code has not caught up with reality.

Ideally the support wall for the soffit should be attached at ceiling and floor increasing the load capability of the wall against the forced that a cantilevered structure (such as a soffit) will put on it.

Think of the way a nail can be pulled out of a bit of wood if you grab the head pulling along the length of the nail - now compare to the cross forced required to pull a nail out of a bit of wood going 'side to side' the nail is stronger and require far more force to pull it out of the wood if its being pulled sideways compared to upward. Due to these forces we tend to toenail nails when nailing to prevent pulling out.

Around here the counties do not agree on wall and soffit structure similar to what you describe. Meaning in some instances a wall can be a partial wall with a sofit on top, while in other cases the wall must extend the full length of the distance between floor and ceiling.

Soffit design is usually more of a process of aesthetics than functionality. We do not usually install a soffit across part of a room - we usually continue it across the whole span so the space is pleasing to the eye. It is even common to put in a 'useless' soffit around the whole perimeter of a space just because it looks nice. More often than not a soffit is greater in size than it needs to be - not because of functionality but because it looks nice.

Depth of the soffit or the finished look of the room may be of more interest than just the structuring. Meaning if you think that the soffit will look better extending further into the room, then moving the pipe is the solution even if local code will allow a partial wall supporting the soffit attached to the wall.

I have made the assumption that this is not a load bearing wall, if it is bearing a load (the upper floor/roof) then it must be one continuing structure from floor to ceiling.

From personal experience I have found that moving a pipe out from a corner (where wall meets ceiling) to install a stud wall) means far less cuts and potential errors in putting the stud wall up. Attaching anything to a masonry wall is a lot of hard work. It is easier to attach your plates to floor (concrete or other wise) and ceiling - you end up with a stronger structure.

Building code in many instances is just minimum. Where as the local code may allow a partial wall, that doesn't mean that the structure is better than a full stud wall with soffit on one side. It only means that it is minimum allowable structure.

When in doubt call the local building inspectors office somebody there will be able to tell you what is and is not allowed if you explain it. I think (this is just a thought) that for a non-load bearing wall the problem will be one of ease of construction and the aesthetics of the final product.

To compensate for the lack of U.S. drywall and wallboard when constructing new homes during Florida's housing boom a few years ago, contractors resorted to importing Chinese drywall.
This drywall has been linked to an odor of rotten eggs and to health disorders like irritated eyes, breathing difficulty, bloody noses and headaches. This defect has affected hundreds of homeowners in Florida, primarily in homes built in the last five years.
If you think your home is built of defective Chinese drywall, please contact my law firm, Dewey, Cheatham, & Howe

Edited with Glee

This message has been edited. Last edited by: DorianGreyed,