Ceiling Crack 2

[TJT]

Hello,
I've been struggling for years with a crack in my ceiling that spans about 10 feet, seperating my living room and dining room. This is on the upper floor of a 20 year old house. Twice I have had the drywall repaired only to have the crack reappear within six months. Initially I thought it could be due to the snow load as sometimes we have up to 3 feet on our roof, but the crack sometimes appears bigger when there is no load on the roof. I have had the roof structure inspected and I did verify that the beam that spans the room is properly designed. There are only a few minor cracks in the foundation and none of them seem to be getting bigger. The crack starts from the inside wall, radiating to the outside wall. There is a support post in the basement, below the inside wall. There doesn't appear to be any visable damage around this post. I'd like to fix the ceiling for the last time. Would adding an adjustable support beside the basement post help with this problem or should I be looking at a different solution.
Thanks...Tim

 

[Focht3]

Where is your house? Do you have any other problems with doors, windows, etc.?



Please see FAQ731-376 by [blue]VPL[/blue] for tips on how to make the best use of Eng-Tips Fora.

 

[ishvaaag]

The causes may be many, but without seeing is difficult to say. The behaviour you describe happens typically seasonally in soils that show seasonal variations of volume normally on water availability, and in fact my aunts own a maybe nearly 200 years old house the walls of which (made of tapial, or uncooked dried mud with straw and sometimes lime) show one of such cracks. Part of the house hinges at the bottom of such crack bringing it down towards the river nearby, then closes a bit and so every year.

Contrarily, the cracks that do not move rithmically and are directly associated to the settlement of the foundations use to stay or in any case grow. Of this I have one as well at the same room where I sleep, heh. The building has settled under the dishing action and the corner -where such room is- attempts a bit of separation, since settlement there seems be lesser than under the center ... this crack is most noticeable in the floors (both floor and ceiling show it, and I muse many other floors in the condominium building also will). This, happily has stayed stable for over 20 years -even if it moves, it does little, since no appreciable growth of the crack is seen- so it was no doubt produced but under primary settlement, and maybe final, since I have no knowledge of what soil lays under the building.

If you have a seasonal crack it will be difficult to solve because for such thing doing maybe you should revamp your foundation and building to such extent that so costly measure is not worth the hassle of an unaesthetical crack. In any case, it is good that some competent structural designer examine the thing mainly to ascertain if there is some faulty structural component, or detect if there are signs of progression that may lead to failure or lack of serviceability.

 

[wolfhnd]

Cover the ceiling with a non woven polyester fabric and then a canvas. This a traditional solution used for centuries on plaster ceilings. If you need more help on where to get materials let me know.

 

[RDK]

Depending on soil conditions the crack could be moisture related.

Clay soils will shrink and expand with loss and gain of moisture.

This loss and gain may not be directly related to the seasons but more to the rainfall in the past few months.

There might not be anything you can do about this crack. Wolfhnd's suggestion is most likely the best thing that you can do for this situation.

If that does not work, try getting a vine to grow over the area.


Rick Kitson MBA P.Eng

Construction Project Management
From conception to completion

http://www.kitsonengineering.com

 

[boo1]

If there is not any structural deficiencies:
We use self adhesive fiberglass tape, then re-mud.