Watch the new episode and learn how to identify different structural cracks.

[Nick Gromicko]

http://www.nachi.tv/episode63

[john bubber]

1:05 mark, What causes VERTICAL cracks?
The answer given is.....upward lift or settling.......no mention of
lateral soil pressure. Vertical crack can also be caused when wall(s) was
backfilled,the use of equipment near wall or as the SOIL 'settles' against
a wall and other possibilities.
Lateral soil pressure 'caused' these cracks... http://www.lrb.usace.army.mil/Amhers...os/photos.html

U S Army Corp says.....lateral soil pressure caused the stair-step crack...
caused the vertical crack....
caused wall to bow inward.
If you read the Amherst/Corp full soils report/study,FOUR SOURCES likely contributed to lateral pressures on basement walls in Amherst....
1.pressure from soil weight
2.pressure from soil swell
3.hydrostatic pressure (against outside of basement wall) see Yoder link
...'horizontal hydrostatic pressure'
or Vila link 4th para, 'pressure against a basement wall when the soil is thoroughly soaked is called hydrostatic pressure...it can CRACK or buckle wall'
4.pressure from frost

http://dwightyoderbuilders.com/concrete.cfm
Here`s one builder that has NO complaints, says in part, 6th-paragraph
...'saturated soil against outside wall(s)-horizontal hydrostatic pressure
can cause cracks,leaks and in worst case cause wall to bow inward'
Those cracks can be, vertical,step and horizontal.

http://www.bobvila.com/HowTo_Library...ion-A2095.html
Vila didn`t write this (pfft), most of article is right on........among other
things it says,first paragraph.... 'OFTEN,however, the BIGGEST load on the
foundation is NOT the weight of the house, but the pressure of the
soil around the foundation.Called the lateral load....'

Those caissons are subject to lateral soil pressure just as basement walls
are,not only possible heave.

Quite a few homeowners can have cracks in bricks that are caused when
the foundation wall has cracked or bowed inward due to lateral soil pressure or water can get behind/through bricks that may cause bricks-
joints to cracks etc. Its not always or most often due to possible heave-
upward lift/settling.
http://www.fairfaxcounty.gov/DPWES/p...marineclay.htm
See... -Basement Wall Damage,cause and resolution.
Cracks in bricks/joints can occur if/when a crack occurs in basement wall
or basement wall bows inward,doesn`t necessarily mean any-all problems cracks are mostly-always due to supposed upward lift/heave from below.

Basement walls here have horizontal,step and vertical cracks and,bottom course of blocks have deteriorated,its due to lateral soil pressure and underground roots.
http://www2.snapfish.com/slideshow/A...6/t_=122238283


http://www2.snapfish.com/slideshow/A...6/t_=122238283

[Kenton H. Shepard, CMI]

Most of the cracks I've seen that were from lateral pressure were horizontal, but here's one that wasn't.