Although a crack might seem minor or small, it can grow much larger and cause water to leak inside or even result in the loss of structural integrity of the foundation.
Reliable Basement Services has sucessfully repaired THOUSANDS of basement cracks over the years with an extremely high degree of success. Our skilled professionals can fix these cracks permanently using high-pressure injection of polyurethane foam repair materials or low-pressure injection of epoxy resin, without the need for disruptive excavation. Crack injection has been used successfully to repair foundation cracks for many years.
So which material is better for repairing cracks in a poured concrete foundation: epoxy or polyurethane foam? The answer isn't always clear-cut. In many cases, either material can accomplish the task. But here are some general guidelines: If the crack needs to be structurally repaired and the area needs to be as strong or stronger than the concrete around it, use an epoxy. If the crack needs to be repaired only to prevent water leakage or the crack is actively leaking, a polyurethane injection is the best choice. Here's a look at the advantages and limitations of each material.
The main advantage of epoxies is their amazing compressive strength, which at 12,000 psi or greater exceeds that of most concrete. That's why epoxies are the only choice for cracks requiring structural repair. However, epoxies cure very slowly, generally taking hours to harden, so it's possible for the epoxy to flow out of the backside of the crack before it has hardened, mostly if the backfill outside the wall has separated from the foundation.
If the main concern is water leaking into the basement, polyurethane foams should be used. These elastomeric, fast-setting foams are most effective for applications involving only crack sealing (waterproofing) and not structural repair. It's expansion factor will allow the material into even the smallest crevices. Due to their elastomeric nature, they are able to accommodate slight concrete movement so over time the seal stays intact. They also begin to cure within minutes of injection. This reduces the chances of the material flowing out of an injected crack while still in liquid form, and even if some does leak out, the foam and its expansion will fill the void. Urethane is great for basic foundation crack filling. They add almost zero compression strength, but in most residential applications, you do not need it.
Many homeowners in Chicago may be tempted to use caulk or hydraulic cement to patch concrete cracks. Caulk is a temporary and superficial solution and will allow water to continue seeping behind the material. This results in efflorescence, and eventually the caulk will crack and peel off exposing an enlarged crack due to freezing and erosion. Hydraulic cement does not bond well, also leading to efflorescence. Eventually, the water seepage will dislodge the cement plug.
Reliable Basement Services has nearly a 100 percent success rate for crack repair work; and we offer a lifetime warranty for the injection repairs because we are confident in the manufacturers dedication to improving the materials and techniques offered, and the training of our staff.
Injection products create a win-win situation for Reliable Basement Services and you, the homeowner. We can reliably fix a major inconvenience, while saving you thousands of dollars for more extensive repair work and avoiding the disruptive effects of exterior excavation.
Avoid do-it-yourself basement crack repair kits if possible, there are no money back guarantees with foundation crack repair kits. If the repair doesn't work you have thrown money away. Also when selling the home new homeowner's generally require warranties for the work that was done.
Shrinkage cracks are usually uniform in width or (less common) V-shaped, wider at top and diminishing or stopping before reaching the bottom of the foundation wall (where attachment to footing may tend to hold foundation wall materials in place). A wall crack which continues into the floor is likely to involve the building footings and may be a settlement crack of more structural importance.
Concrete shrinks as it cures. In poured concrete, shrinkage cracks may be non-uniform if wall components are held by footings/framing; very often there are minor shrinkage cracks which are hairline, random, intermittent, multiple, and meandering in the concrete. Shrinkage cracks occur as concrete cures, appearing more frequently and larger if the mix was improper and where control joints were omitted. Omission or the pattern of placement of steel reinforcements may also be a factor in crack formation and location.
Usually shrinkage cracking is due to conditions created at original construction: poor mix, rapid curing, and variety of other factors. Shrinkage cracks are less likely to require structural monitoring and repair in poured concrete as they would not be expected to continue after initial curing.
Concrete block foundation walls shrink as they cure. They rarely expand much on exposure to moisture and temperature variations. In concrete block walls shrinkage cracks are likely to be uniform in width and usually occur towards the center of a concrete masonry unit (CMU) wall. The wall is stronger at the building corners. CMU Walls cannot be injected like a poured concrete wall, different repair methods will be required to fix a leaking CMU wall.
Brick walls do not normally shrink, but rather, grow indefinitely. Bricks are not often used for below-grade foundations but were often used above-grade supporting the first floor of older buildings, and of course entire buildings may be constructed using structural brick walls (look for the bond courses). If you see a crack in a brick wall it's more likely due to movement in the structure, a support problem, or due to thermal expansion. Cracks in structural brick walls may be very serious if the bond courses are broken as there is then a risk of sudden catastrophic wall collapse. Cracks and especially bulged cracked brick walls need immediate expert investigation.
Stone foundation walls do not normally crack through individual stones, but the interlaced stone layout of the wall may be bulged and cracked due to damage from frost, loading from driving vehicles near the wall, or by the removal of stones to pass piping or make doorways. As with other cases of foundation movement, a diagnosis of the cause, amount of movement, and effects on structure are needed to decide what repair may be needed.
Clues to help diagnose the probable cause of diagonal foundation cracks in buildings: From corner towards adjacent opening, wider at top than bottom - often due to foundation settlement, expansive clay soil, frost damage, or damage from a shrub/tree close to the wall. Under a ground floor window, from sill to ground, sill bowed up - often due to foundation heave, clay soil, frost, shallow or absent footings. In the foundation wall anywhere, wider at bottom than top - settlement under building At building corners in cold climates - frost heave, frost lensing, shallow footings, water problem, or insufficient back fill. In a typical raised ranch with a garage located in part of the basement, and with the garage entering at one end of a home, we often find step cracks in the front and rear foundation walls only on the garage-end of the home. These cracks may correspond to some related observations: (1) there may be less backfill against the front and rear foundation walls where a garage entry is located between them; (2) the reduction in backfill combined with an un-heated garage may expose these building corners to more frost damage; (3) if a building downspout or gutter defect spills roof drainage against the building wall, these forces will often combine to make more severe frost cracks appear on the garage-entry end of the home. Vertical or diagonal cracks which over a short time - settlement over sink holes- serious, open suddenly after rain; or ravines, mulch, fill, organic debris (later rots and settles). Over window/door, straight or diagonal - loading/header defect - may appear as horizontal along top or bottom of header, vertical at ends of header (possibly due to differences in thermal expansion of different materials of header vs. wall) or vertical/diagonal at center of header (loading failure) or at corners (possible point-load failure) Cracks in a poured concrete foundation which are diagonal or vertical and which are generally uniform in width, or which taper to an irregular hairline form, usually in fact a discontinuous crack in the hairline area, are usually shrinkage cracks and should not be ongoing nor of structural significance, though they may invite water entry through the wall.
Horizontal Foundation Cracks Located High on a Foundation Wall - Horizontal cracks located in the upper third of a concrete block wall (assuming most of the wall is below grade) are most likely to have been caused by vehicle loading or in freezing climates, by surface and subsurface water combined with frost. In northern climates if we see cracked mortar joints in the top third of a block wall, at about the same depth as the frost line in that area the damage is almost certainly due to frost. Often outside we'll find corroborating evidence such as drip lines below the building eaves confirming a history of roof spillage against the building, and back inside we may see that the foundation damage is occurring only at the building walls below roof eaves and not at the gable ends of the home.Cold climates- frost, possible displacement inwards Possible vehicle loading, displacement inwards.
Horizontal Foundation Cracks Located at Mid-wall Height on a Foundation Masonry block or stone walls which are cracked and/or bulging inwards at mid height on the wall are likely to have been damaged by vehicle traffic or earth loading These cause are described below: Possible vehicle loading (look for a driveway near the wall or site history involving movement of heavy equipment near the wall) Backfill damage - excessive height or premature backfill before the first-floor framing was in place. Hillsides - earth loading or earth loading exacerbated by water or frost. Areas of wet soils - likely to be earth loading or earth loading exacerbated by water or frost.
Horizontal Foundation Cracks Located Low on a Foundation Wall - The forces exerted by soils against a foundation wall increase exponentially as we move from surface level of the soil against the wall to the areas near the bottom of the wall. In other words, earth pressure is greatest at the bottom of the wall. This fact helps us distinguish between frost or water-related cracking and simple earth loading in some cases since a wall which has become dislocated laterally only at or near its bottom is likely to have been damaged by earth loading. Horizontal dislocation of a masonry block or brick wall may appear first as a crack and then later as horizontal movement as a wall is pushed inwards by earth or wet soil pressure.
Cracks in a poured concrete foundation which are diagonal or vertical and which are generally uniform in width, or which taper to an irregular hairline form and stop entirely, which are usually discontinuous in the crack's finest or hairline area (the crack "stops and starts" in the same area), are usually shrinkage cracks and should not be ongoing nor of structural significance, though they may invite water entry through the wall.