How To Fix Cracks In Cinder Block Walls
Major Rowley
Yes, you should be concerned. Cracking like this is caused by movement (the structure has moved, such as settled) and this type of cracking is unusual. This needs to be reviewed in person by a structural engineer who can look at the particulars of your situation. This is not something that you can get a good answer for here on this or other sites.
Being a corner and a mid block crack I would say yes there is an issue here. It could be the attached building footing sinking but mid block cracks are really bad I have only seen them in walls that were not properly filled, or some that were not filled at all. But a mid block fracture over this many layers or courses needs a engineering review and proactive repair before major structural failure.
Cinder blocks are building materials made from concrete and coal cinders. They are sturdy, fireproof, and inexpensive, making them popular for construction projects. The hollow rectangular blocks can be stacked and mortared to form walls for homes and other structures. For decades, their durability and low cost have made cinder blocks a fixture in residential construction.
Inspection today I found stairstep cracks on three out of 4 exterior walls. Cracks seemed to start in center and run for 6 ft or so and peter out in both directions with the widest point in crack being more towards the center of the wall (vertically).
Walls had rebar at aprox 36 inches o.c. and no signs of cracks on interior of house. I usually describe concrete cracks as spider cracks that can be sealed and painted over but these were more excessive. What are your thoughts?
I have no idea how many coats of stucco. How could you tell? I compared the density sound by hitting with a rubber mallet and my walls on my cbs home are considerably more solid. The pics are decieving. I should of took better pics but two of the cracks you could easily get a pencil lead inside. Personally I believe it was not grouted properly. I am recommending further evaluation by a structural engineer.
Some cracking on the walls was noted in a few areas around the perimeter of the dwelling. These generally appeared to follow the mortar joints between the courses of blocks (stair step pattern) and are a normal occurrence found in homes of this design. We did not notice any wall deflection or evidence of racking to doorframes or window openings in these areas at the time of the inspection. We recommend these be sealed and monitored for further movement.
Epoxy would be my choice, but it really won't do much for you since it is stabilized already, unless you are also willing to dig down outside and do the same to both sides of the wall, presuming that you have the same crack through it.
I'm matching tool donors to a church mission to Haiti - we're shipping a bus converted to a medical facility in (now it looks like) April and can fill it with clothes, tools and all sorts of stuff needed in that poorest of all countries. A few hand tools or power tools can provide a livelihood for an otherwise destitute family. Please email me if you have tools to donate.
Epoxy injection would probably not be the way to go for cinder block. Too many voids. Epoxy injection is suitable for smaller, hairline cracks. Not to mention, most epoxy injection contractors charge by the amount of epoxy injected, and with large voids, this will get really expensive fast. Also, epoxies won't set up properly if the void is too large - I think it's anything over 1/4-inch. Epoxies generate a lot of heat while they set up - too much if you have too much epoxy.
So, to summarize, epoxy does not make sense for wide cracks and is out of the question for large voids (such as the interiors of cinder block). This is helpful to know. How about if I used a combination of filling the voids with expanding foam (slow expansion), then trimmed the foam back to reveal the crack. I would then have the epoxy injection along just the crack area. Or would it just make more sense to properly point this crack with appropriate the mortar after filling the voids with foam?
As to the question of digging down outside and fixing the cracks inside and out: this is a "walk-in" basement on the side with the cracks and digging is not an issue. I plan to to interior and exterior fixes and do them proper.
I think that's what he means. In block construction it's common to fill certain cores, say, around a vertical rebar, or on both sides of a door opening with a fairly loose mix. The process is called "grouting". You'd have to make up a quick form, say a strip of 3/4" plywood, and brace it against the wall to cover the crack so the grout won't ooze out.
yes, I would just use plain grout between each end of block, if it was in the center of block I use some peagravel. My whole house is filled every cell to ridge line, only eight yard. But one seam one crack couple bag cement maybe a wheel barrow load or less.
I guess the only problem that I have now is that these are the old-fashioned faux stone blocks (where the exterior side is textured to look like wavy stones). Although sealing the interior with a form will be simple, doing so on the outside would be a little tricky. My only thought on how to do so would be to apply duct tape over the crack.
Perhaps no question is more important in discovering the cause of foundation block wall cracking than this. Different types of pressure will generally cause differently shaped cracks. Here are a few examples:
Finding a stair step or diagonal crack zig-zagging up your concrete block wall is usually an indication of soil pressure or settlement. If you see this type of crack in conjunction with other typical signs of foundation problems, there is a good chance that uneven settlement is causing the issue.
It is a good idea to have this type of crack inspected by a foundation professional. Although the crack doesn't always indicate structural problems, the possibility is likely enough where it is a good idea to have it checked out.
These cracks are often caused by external pressure, likely hydrostatic (water) pressure from the surrounding soil, pressing the walls inward. A horizontal crack can also appear as a result of a one-time event, such as backfill damage.
If the cracks are caused by an ongoign issue, they are the first step. If the issue is left unchecked, the wall will likely bow and possibly shear or fail. The earlier the problem is caught, the less intrusive the repairs likely will be, so don't put off contacting a professional until it looks like the wall is in danger of imminent collapse.
If you have a concrete block wall crack that you even suspect might be structural in nature, the next step is to contact an experienced foundation repair specialist to diagnose the cause of the crack. My Foundation Repairs has a nationwide network of foundation repair contractors who are highly trained and use only high quality foundation repair materials. Let us help you find a contractor in your area.
If you are reading this post you likely have a basement leak which you believe to be the result of one or more cracks in your cinderblock (or concrete block) foundation. While this is often the case, foundation cracks are not always responsible for the water in your basement. Interestingly, a good number of wet basements are caused by the water table rising rapidly after heavy rains or when substantial amounts of snow melt quickly. The presence of cracks in a cinderblock foundation may well be the main source of water ingress into the basement.
It cannot be stressed enough that determining the best method to employ to waterproof and repair your basement must be based on what is actually taking place at your home; understanding how your basement is getting wet, and the condition of the foundation, are of paramount importance.
Once ground water penetrates a cinderblock foundation wall, the hollow cavities in the blocks will fill up with water. If the water in the blocks cannot escape, the walls will seep because the cinder-blocks are porous and allow moisture to wick through them.
The effect of pooling water in cinder-block foundations
For most homeowners the foundation cracks are minor and the only issue to contend with is the basement dampness or basement leaks. There are two methods to waterproof block foundations: one is the installation of an interior perimeter drain system (which means no digging!) and the other is customary excavation and waterproofing. Just follow the links below to learn more:
Note: Sometimes waterproofing part or all of a basement becomes a condition of the sale of a property. It is regrettable that in some cases, structural cracks get concealed during waterproofing activities.
The repair of structural foundation cracks is a topic of discussion in its own right. Dealing with these types of cracks requires experience and expertise which is impossible to discern by talking to a basement waterproofing company receptionist. Read more for comprehensive coverage of this topic.
I just noticed a stairstep crack in the wall of our garage. It's pretty much a hairline, max 1/32" and shows no sign of water ever coming through. There is no bowing of the wall that I can detect with a straightedge. The wall is backfilled all the way up, sandy soil, except for the top 6" or so. There have been no traumatic incidents to the wall such as a car bumping in, excessive ground freezing etc.
Stair step ,sounds like they are on the joints
How bad,hmm,depends upon what is inside the wall, especially since it is back filled all the way up.Best case it would have vertical ,rebar ,horizontal wire in every other joint,and filled with grout,waterproofed before backfill,and laid on proper footing,and back filled loosely.So it could be somewhere less than this and still be fine,or a pitiful job.Sorry but it would just be impossible to say.Good luck