Typical cost in Kirkland
A house that sinks or leans needs its cause found before a pier is chosen. Kirkland Foundation Repair explains push piers, helical piers and underpinning for Kirkland houses, what each does and where it stops. The aim is a stable foundation. Lifting the house or levelling the floor is not promised.
We cover Kirkland, with Kenmore and Clyde Hill nearby. A median build year of 1984 and a Kirkland housing stock where 37 percent dates from 1960 to 1979 means houses whose footings have had decades to show what the ground under them does.
HUD’s foundation guide calls them mini-piers, and contractors call them push piers: steel tubes between 2 and 8 inches across, hydraulically driven next to the footing down to rock or a sound bearing layer. The guide also lists what can go wrong, which is cracked foundations and slabs if they are used incorrectly, and a bearing layer that has to be fairly shallow for the method to be economical.
A helical pile is a manufactured steel product, an Iowa State guide says: a lead section carrying one or more helices, coupled to extension sections and rotated into the ground. HUD also reports that installation torque can be measured to determine bearing capacity, and it lists soils of limited bearing capacity as unsuitable.
People search for “underpinning” and mean two things. One is enlarging a footing, which HUD says needs an engineer’s design so the new footing is sized for the soil. The other is pier work. Ask which one a proposal means.
Signs to watch: sloping floors, a door that no longer meets its frame, cracks leaving the corners of openings, and cracks that taper. HUD observes that settlement generally happens gradually, which leaves time to research the cause. A leaning wall or an active slope is the exception and calls for a prompt call.
Before a visit, put a level or a marble on the floor in a few rooms and photograph where it goes. Measuring the same spots again a month later shows whether anything is moving.
HUD’s foundation guide groups the causes of foundation failure under five headings
Poor soil, in its examples, means peat and other organic soils, silty soils and fill that was not compacted in layers. Water adds to the problem: it can carry fines out from under a footing and weaken the soil.
Washington DNR’s Bulletin 78 says peat settles heavily under load and when it dries, and puts most of the state’s peat in the Puget Sound basin. A soils report, not a guess, says whether one lot has peat or fill.
Piers are about transferring the load of the house to deeper soil. HUD notes that raising a settled foundation more than a few inches is difficult with augered concrete piers. We will not promise to bring a floor back to level.
A pier design depends on the soil under the footing, so the plan comes from what is found there. Where the cause is unclear, or the lot is a hazard area, a geotechnical engineer is asked first.
Cost depends on how many piers the load calls for, how deep the bearing layer is, what has to be dug out to reach the footing and whether a deck, stairs or landscaping is in the way. An engineer’s design and a geotechnical report, if the city asks for one, are separate from the contractor’s work.
Kirkland’s zoning code covers erosion, landslide and seismic hazard areas, including those on the Landslide Susceptibility and Liquefaction Potential maps. The code treats the maps as guides and requires site-specific geologic studies before development or land surface modification is approved. It also allows the city to require a geotechnical investigation by a geotechnical engineer or engineering geologist licensed in Washington.
That is a critical-area rule, and the Development Services Center can say whether piering at your address needs a stamped design. Look at King County’s landslide map and the state DNR portal for your address first.
Sloping floors, a door that no longer fits its frame and cracks that taper or run from the corners of openings are the signs to watch. Dated photos and a repeat measurement a month later show whether it is moving.
A push pier is driven down beside the footing to a bearing layer. A helical pier is turned into the ground like a screw. Each suits different soil, and the soil under your footing decides.
We do not promise that. The work aims to stabilize the foundation. How far a settled house can be raised depends on the structure and the soil, and some pier methods raise it only a few inches.
A crack with no sign of movement behind it belongs on foundation crack repair. Other kinds of work are summarized on the Kirkland Foundation Repair home page.
Tell us what you see: sloping floors, door gaps, corner cracks. Say how old the house is and what is next to the affected corner, such as a downspout, a slope or a retaining wall. 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) 522-5661