After living in their house for over 10 years, Kathy & Scott had their deck and 4-season porch footings heave. The locks on their double hung windows popped off and shot across the room when the heaving forced the windows up at an angle.
Why did this happen? Most likely do to a really rough (and wet with snow) winter that forced the frost down deeper than it ever had before. Compile that with heavy clay soil and you get a recipe for disaster. After reviewing the original building plan, the original concrete footings appeared (on paper) to be installed correctly and up to today’s building code requirements.
The solution J Carsten Homes presented the homeowners was fairly simple- remove the concrete footings and install Helical Piers for the new foundation. A helical pier is essentially a screw that is advanced into the ground until the proper torque is met (based on a PSI reading). The depth of the helical pier will vary based on the soil conditions. For this job, the average depth was 12 feet. After the pier is installed, a 12 inch square metal plate is welded to the top of the pier. The new post for the 4-season porch and the deck sits on top of the metal plate with Simpson-type post anchor. The installation contractor then tack welds the Simpson-type post anchor to the metal plate and cuts off the excess metal around the post. That’s it. Ready to go the same day.
The benefits of the Helical Pier foundations are great:
1) Ready to be used immediately- no waiting for concrete to dry and no backfilling is needed
2) Less damage to yards and landscaping. The installation machinery is a mini-excavator with tracks. One trip in. One trip out. With concrete, the concrete truck will either need to back up to the location of the footings, which will leave some deep tire tracks in the lawn, or the concrete will be hauled to the footings with numerous trips over the lawn.
3) Helical footings are virtually guaranteed never to move. Even concrete installed properly and according to building codes can still move.
The only draw back from the helical piers is the cost. They cost about 4 times as much as a concrete footing. But you can make the choice. If your installation involves difficult soil conditions, the extra money may be worth the peace of mind.
Check out the installation of the Heilcal Piers for this project: