Typical cost in Renton
Renton Foundation Repair looks at cracks in foundation walls and tells you what they are doing before suggesting a repair. A crack in concrete can be nothing, or the first sign that a wall is moving, and the repair that suits one is wrong for the other.
We serve Renton and nearby Kent and Tukwila. Houses here date from several eras, and block and poured walls crack in different ways, so the age and construction of the wall come into the diagnosis.
A hairline that stays the same size is the mildest case: HUD calls shrinkage cracking rarely serious, and an extension-service guide expects concrete and block foundations to collect a few cracks. Keep an eye on it and seal it if water gets in.
A crack that gets wider toward one end can indicate differential settlement, according to HUD. Sealing it does not address the movement, so the cause comes first. A crack that steps through the mortar joints of block is worth asking an engineer about.
Horizontal or sweeping cracks in block and brick walls are read differently. HUD ties them to causes outside the wall, such as badly placed backfill, heavy vehicles working close by or soaked soil leaning on it, and none of that is settled until someone looks on site.
A crack that has not changed in a year is a different problem from one that has doubled. Mark each end with a pencil and the date, photograph it with a ruler beside it and look again after a rainy month. HUD’s guidance adds that minor settlement cracks become structurally harmful when long-term leakage through them damages other parts of the building.
HUD gives 1/16 inch as how far a waterproofing coating is meant to bridge a nonstructural crack; that is a coating limit and no verdict on the crack itself.
Sealing is done with a surface coating, or by injecting a resin such as epoxy or polyurethane into the crack. Which one fits depends on the crack and on whether the aim is to rejoin the concrete or to keep out water. No method is guaranteed to stay watertight, and a crack that is still moving can open again beside the repair.
That is why cracks that move are handled as a settlement or water problem first. See foundation settlement and piering and foundation drainage.
HUD says a structural or soils engineer should be consulted about the cause of settlement, and says horizontal cracking in block or brick walls may be potentially serious, with the cause confirmed on site. A crack that is wide, still widening or horizontal, or doors that have started to catch, are worth asking an engineer about. This is advice, not a Washington permit rule, and we do not provide engineering.
Renton’s critical areas code groups steep slopes, landslide, erosion and seismic hazards, and coal mine hazards, as geologically hazardous areas. If a wall that needs repair is on or near such an area, or sits behind a tall retaining wall, ask the permit center what applies before work starts. The city’s code lets some critical-area exemptions apply only after a letter of exemption from the administrator.
A retaining wall 48 inches or taller, measured from the bottom of the footing to the finish grade at the top, always needs a building permit, and so does a shorter one that supports a surcharge.
Which side can be reached depends on the house. Whether the inside is enough depends on what the crack is doing and what is behind it.
HUD describes shrinkage cracking as rarely serious. Mark it and see whether it changes, and have it looked at if it grows, tapers or lets water through.
We do not promise that. Injection can seal a crack that is stable. If the wall is moving, the crack can reopen.
Look at the crack again in a month. If it has grown, the cause is probably not the concrete itself: foundation settlement and piering and foundation drainage cover movement and water, the two causes HUD ties to cracking. The Renton Foundation Repair home page lists every service, including the crawlspace and bolting work.
Tell us where the crack runs, roughly how long and wide it is, whether the wall is damp, and when you first noticed it. We'll get back to you soon with an estimate or any questions we have. Estimates are free and there's no obligation.
Call (425) 276-6261