Cracks in Walls of House

[esotiro2]

Hello everyone,

This is my first post here! My husband and I bought our first house a month ago. We live in Central Illinois. Our house was built in 1964 and the realtors and home inspector all commented on how well-built and well-maintained this house has been. We've had a few contractors come in to give estimates on repairing bathrooms, and they, too, have said that the house is very well-built.

You'd think that'd be enough to settle my nerves, right?

It all started when the inspector noted that we had a cracked floor joist that needed to be repaired. This floor joist is located under our dining room, which had a bouncy floor (after we moved in, the handles on my hutch would jiggle whenever you walked through the room). I started to really look at the details of our home. In this dining room, there is a crack where two walls of the dining room meet. The inspector said it could be from the drywall pulling away from each other. On the other side of the room, there is a hairline crack that extends from the corner of the doorframe up to the ceiling. The crack then runs along the ceiling and wall joint.

Right above the dining room is the master bedroom. This room also has a sagging floor, and fairly identical cracks compared to the dining room (re: doorframe corner cracks). The doorframes themselves have gaps in the corners where the two pieces of wood come together. Right off the master is the bathroom, which has the original cast iron tub.

Back downstairs, you can see how the master bathroom is right above the kitchen. You can see how perhaps there was some damage or some kind of repair made at one point, because the faint outline of a square is right under where the toilet was (we've removed it). The ceiling sags ever so slightly, and there are little, tiny cracks. You really have to look to notice them.

I've also noticed that the kitchen wall has "peeled" away from the countertops. In fact, I heard this peeling noise one day and saw what was happening.

I'm obsessing over these cracks. My husband and I placed three jacks on cement blocks under the cracked joist and a few sagging joists (nothing super obvious, but when you hold a 2x10 up to them, you can see how they don't all touch the board). That has taken the bounce and squeak out of the dining room floor. But it obviously doesn't do anything about the master bedroom. I'm convinced that the cast iron tub will fall through the kitchen ceiling and that our bedroom will just fall away from the house!

Our crawlspace is totally dry (for that matter, our house is very dry - extreme static and dry skin!). There are NO obvious cracks in the foundation (believe me, I've checked and checked and checked). No other part of the house has cracking and sagging floors. I just can't explain what's going on with the walls, and moreover, if I'm just being paranoid or if I need to pony up the cash to have a structural engineer come out.

I have a strong background in physics, so I understand a great deal about forces and so forth. I'm just not as familiar with them in practical situations, like in a house!

Has anyone else had these problems? What underlying causes should I be looking for? Is this type of wall behavior pretty typical for a 50 year old house? It's hard to say how long these cracks have been around, although it looks like they've been fixed before and they've come back. I wish I could ask the previous owner.... But he died! So he's no help.

Thanks so much for reading this entire post!! I appreciate any answers you might have. I'm looking forward to reading up on what others have done to their house - we are knee deep in projects right now!

[pushkins]

Firstly, I doubt your in any serious risk of the tub falling through the ceiling, while it's cast iron and heavy, it's weight is distributed across several floor joists whose weight is then again distributed across the lower level walls and then the foundation, not a single cracked floor joist.
The cracked floor joist should without question be repaired (sistered) or replaced.

As for the "bouncy" floors, that's not such an unusual occurrence back in 64' building codes were very different and span charts for floor joists have changed since then, now wider lumber is required for the same span for example in the past a 2x10" floor joist could span up to a max. of up to almost 17', now the same lumber (assuming same species) has a max. span of 15'3". This does not mean in any way your house is/will fall down, it was just a way to stiffen floors.
It sounds like you have addressed the "bouncy" issues by installing jacks in the crawlspace, this is a standard way to fix this issue, I always use (either solid 8"-12" poured foundations/difficult to do in a crawl.) or double solid 8"x16"x4" concrete blocks.

The square you make mention of in the ceiling sounds to me like a toilet waste line repair, it's much easier and cheaper to repair plumbing from the drywall side rather than the tiled/vinyl side for obvious reasons.

Most often cracks will appear or be more noticeable in drywall in winter months, this is caused by the drying out of the interior atmosphere, hence the use of humidifiers in winter months, if you have one installed with your furnace it might be a good idea to check to make sure it's working or increase the setting a little at a time. (High static is the perfect indication of very low humidity). This in my opinion is most likely the cause of what your seeing with the hairline cracks, they were already there just not noticeable....you know that old expansion and contraction, everything on the planet does it in some way or another we don't notice it so much on the interior of our homes as we acclimatize them with A/C and Heat and the swings between the two are pretty small.

The biggest factor in serious structural issues is the foundation, generally speaking the foundation will tell you more about the structure than anything else and it's usually pretty easy to see with either cracking bricks or worse a crack that zig zags through the mortar line in a diagonal fashion (most often seen near corners).

Is the drywall crack almost a perfect straight line up from the door corner towards the ceiling ? If so this sounds more likely to be a drywall joint (between two sheets) when dry-walling you should not have joints near doors or windows for this very reason. You should cut the hole out of the middle of the sheet for the door or window so the joints are either side of the opening or at the very worst the joint directly over the middle of the opening.