# Wall moves due to temperature changes?  Help?



## mrsccincy (Nov 1, 2012)

Hi there!  I was hoping someone could help me with a problem we are having with a wall in our new home (less than 3 years old).  (I would go back to the builder, but they went belly-up...so I digress.)  

So here's the situation...the wall is an exterior wall.  It extends the height of our 2-story entry/staircase.  It is not load bearing.  We started noticing that it was "bowing" in the middle of the staircase last winter.  At it's widest point you could see a 3/4 inch gap along the baseboard.  The baseboard and drywall bowed away from the stringer.  (I hope I'm making sense here...I posted photos below).  We called out a structural engineer to see if it was built incorrectly and he confirmed that it was indeed built correctly.  Once spring came around the wall moved back into place.  We decided not to caulk or trim it because we wanted to see what happened when it got cold again.  Low and behold, it got cold this week and it is starting to move again.  Argh...I'm so frustrated!

We don't know what to do.  The structural engineer assured us that it is safe, but it looks hideous.  Any ideas how to fix this?  Would insulation help?  Can we trim it in a manner that allows for fluctuations?  Thoughts? 

(Also, if you think I should be posting to a different board please let me know.)  

Thank you!!!!


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## Wuzzat? (Nov 1, 2012)

How did these experts account for your house's symptoms?  If they "don't know", what are reasonable steps to find out?
My guess is that this non-load-bearing surface is bearing some load.

The amount the wall is compressed in a vertical direction such as to cause a 3/4" deflection in 16' 
can be calculated if the shape of the wall is known.  
This curve could be a catenary but the engineering toolbox section on load bearing vertical beams may have the equation for this type of curve.

If you think of the wall as a column with an unusual cross section, then, maybe. . .
http://www.cs.wright.edu/~jslater/SDTCOutreachWebsite/column_buckle.htm

Or, while the wall is curved, stretch a vertical line and measure the deflection from the vertical at several different points.  
Then the compressive distance can be figured graphically.  We could be looking for 1/8" or less, vertically, but we need to know the shape of this surface.
If something is pushing out the wall horizontally at the 8' height the curve of the wall will be different than if the wall is being compressed vertically.

Good problem. 
I'm wondering if it more depends on the humidity of the inside or outside air, rather than the temperature.
Does the ground freeze in winter at your location?
Do the other walls do it?


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## nealtw (Nov 1, 2012)

Is this the baseboard at the landing at the bottom or at the expansion joint level with the upper floor? If this is a raised landing, how high is it from the base of the outside wall?  And welcome to the site.


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## mrsccincy (Nov 1, 2012)

Yep...they "don't know."  They cut a huge hole in our drywall to see if the wall was built correctly and they said it was.  But, they suspected temperature fluctuations...so that's why we waited it out.  The engineer said the only way to fix it was tear it down and rebuild it with steel.


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## mrsccincy (Nov 1, 2012)

nealtw - Just saw your reply.  It's not at the landing.  I just remembered I took photos last year.  I've attached them.  I hope this helps.  Sorry, I'm no expert here.  :-/


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## mrsccincy (Nov 1, 2012)

Wuzzat - We are in Cincinnati so we do get a little bit of ground freeze.  And, no, this is the only wall that does it...thank goodness.


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## Wuzzat? (Nov 1, 2012)

How do you know it's not the staircase stringer that's bowing?  Stretch a line to check.  At this point don't assume anything.

If this is the only visible symptom you may be able to fix this by modifying the staircase trim to allow a gap without it being visible from the staircase.  The stringer top surface at the center would slide under the horizontal trim piece.  

The question is then, "Will the eye be drawn to this uneven width spread over the staircase length"?


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## nealtw (Nov 1, 2012)

When the framers built the house they crowned all the studs to the outside. They do that so that the wall dosn't have waves in it. The crown is changing with changing moisture content. The engineer probably didn't see that it went back by it self but he should have suggested tieing to the staircase. The stair case is extremely strong sideways and is nailed to the studs for support and the nails have pulled out or they were left out. I would open under stairs and lag bolt the stair stringer to the studs. It may not be able to pull them into place so maybe living thru the season and doing it when the wall comes back in place. After the studs are back in place and tight to string a 2x10 can be added on flat to the bottom of the stringer for more strength.


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## mrsccincy (Nov 1, 2012)

wuzzat - The stairwell itself is straight, square, etc.  Good idea on the trimming...might help it not look as obvious.  

nealtw - I actually asked about tying it back to the staircase and the engineer said he was worried about it pulling on the stringer.  Going in from underneath and tying it in makes a lot of sense to me too, but he made me worry that it would ruin our stairwell.  Any thoughts?


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## nealtw (Nov 1, 2012)

I hate to say it, because I allways tell people to talk to engineers but your guy is on drugs. Wood bends and twists all the time. When houses are built walls bend all over the place and are pulled straight and held in place with braces until the next floor or rafters are nailed in place which then holds them straight.


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## mrsccincy (Nov 1, 2012)

nealtw - Ha!  Perhaps he's using the crazy-high fee he collected from us for this job to support said drug problem?  Seriously though, thank you.  You have given me a solution to explore.


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## nealtw (Nov 1, 2012)

I you took an 18 ft  2x6 with a 1" crown it and locked the ends you would find that you could push it straight and one toe nail would hold it there. I would waite until the wall comes back by itself.
Wuzzat; You might build a staircase with a curve but I doubt you will ever bend one sideways.


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## mrsccincy (Nov 1, 2012)

nealtw - Is this what you were thinking?  http://www.oldhousejournal.com/how_to_repair_your_stairs/magazine/1579


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## nealtw (Nov 1, 2012)

With the amount of glue built into modern stairs they won't likely pull apart like that. If the stairs were attachec properly or suffently and the wall really wanted to move you would like find the bottom of the stringer wood break off and go with the wall. That is why I suggested a 2x10 on the flat under the stringer.


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## mrsccincy (Nov 1, 2012)

Okay. Now I get it.  Thank you!


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## nealtw (Nov 1, 2012)

Here's picture of ballon framing, you can see what is stopping the full length studs from bending.


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## Wuzzat? (Nov 1, 2012)

If this problem is not structural it must be cosmetic, so there must be a cosmetic solution that doesn't cause structural problems.  
I think.


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## nealtw (Nov 1, 2012)

This may not be a load bairring wall but it is structure, there by making a structual issue. Good building practice is to nail or attach any components that tough each other in the building. Either this was missed or has failed, so it should be fixed.


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## mrsccincy (Nov 1, 2012)

nealtw - Yes, it was nailed, but the nails pulled out.  When the gap opened to the widest point last winter I could see them.


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## nealtw (Nov 1, 2012)

If it has just started to move you may be able to pull it back now, just start a bunch of large screws or lag bolts and gradually tighten them a little at a time until it comes back tight.


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## Wuzzat? (Nov 2, 2012)

nealtw said:


> and gradually tighten them a little at a time until it comes back tight.


Yes, maybe one or two turns/day to give the structure time to adjust but look for other places to form gaps.


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## nealtw (Nov 2, 2012)

Just another thought, have you checked for leaks into this wall. With properly installed vapour barrier water may never show up inside. It might be worth checking insulation in attic above this wall.


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## nealtw (Nov 5, 2012)

We have had lots of trouble with leaky walls, have a read.

http://www.rdhbe.com/database/files/Leaky_Condos___Why_the_Technology_Didnt_Work(24).pdf


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