Settling Porch, Manchester, NH
Challenge
This home in Manchester, NH was originally built in the early 1900's. The house itself is now a duplex, with an apartment on the second floor and another on the first. The current homeowner purchased the property and had been living there for 10 years when he began to notice the problem. The main concern was with the porch, which had an upper and lower level.
The height of the structure was roughly 20', and it was 32' long by 6' in width. It also wrapped around one of the front corners of the home, and in this section was 12' wide. The entirety of the porch was supported by 6 concrete pillars in sonotubes, piers that were installed sometime in the 1980's. Over time, the concrete pier supports shifted and settled, and by 2020 the porch was beginning to show signs of settlement and sloping.
The homeowner was becoming increasingly concerned with the porch becoming unstable, as he knew eventually the concrete supports would no longer be able to support the porch at all. Worst case scenario, the entire structure would collapse, something the homeowner knew was a possibility. To get the ball rolling with needed repairs, he reached out to Erickson Foundation Solutions to inspect the porch and it's supports, and put together a designed system to replace the concrete pillars with something more stable and permanent.
Solution
Design specialist Paul Magowan designed and proposed replacing each of the 6 pillars with EZ post helical piers. The concrete posts could be replaced by newer sonotubes and concrete, however there are several advantages to the helical pier solution;
- Easy to install, and can be installed year-round.
- The steel support brackets are stronger and more durable than concrete.
- There is minimal disruption to the surrounding area. In this case, the porch did not have to move, and there was minimal invasion of the property's landscaping.
- There is no cure time like there is with concrete, so the porch is stable and secure immediately upon completion.
The homeowner was determined to permanently fix his porch, and so the project was scheduled with our production team. Crew foreman Scott Crandall and his team of Ed and Nick were able to install the 6 piers in just two days. Each shaft installed was 7' in length and placed at a depth that showed a differential pressure of at least 500 psi. Depending on the soil type, this pressure and depth could vary. At this pressure, each pier Scott's team installed had the capacity to hold up to 15,000 lbs, which was more than sufficient for this porch structure.
During installation, the crew also determined a couple of the existing concrete footings were not properly centered for providing sufficient support for the porch. This allowed the crew to install their new piers without having to first dig out and remove the existing concrete. Each pier was installed about 6 feet a part from each other, and combined the EZ helical pier system was able to completely stabilize the porch. Additionally, the production team was also able to slightly lift the porch at the edge to help with correctly the 1 inch in sag that developed over the years, and so the porch was more sturdy and level.
Once all the piers were installed, the team mounted a bracket and placed new pressure treated supports directly over the piers.
Project Summary
Design Specialist: Paul Magowan
Crew Lead: Scott Crandall
Installation Specialist: Ed Nadreau
Installation Specialist: Nate Atkinson
Products Installed: 6 EZ Post Helical Piers
