Structural failures are usually caused by a combination of water and weak construction materials and/or methods. The problems can be compounded by a poor or worn out damp proofing system that allows water to deteriorate the substrate, whether it be concrete, brick, block or wood. Age is also a factor although we have seen crumbling 30 year old foundations and sound 100 year old ones. The chosen repair method must address all of these concerns. If caught soon enough, the walls can be reinforced from the inside with a wood structure and sealed from the outside. The three solutions to a failing wall that we recommend are:
A wood bracing stud wall designed to resist inward pressure and shimmed so that each stud contacts the wall in three places. This is typically for a concrete wall with a horizontal crack and minimal if any vertical cracking.
A wood bracing stud wall with plywood on the backside (adjacent to the existing wall). This wall is built out about 1 ½ inches from the furthest deflected point of the existing wall. We then fill the void between the two walls with grout. This is used for block and brick foundations and extensively cracked concrete foundations.
If the wall is bowed too far or if the construction materials are crumbling, replacement is the only option. We typically replace walls with PWF (preserved wood) construction. This method lends itself well to this type of work by enabling us to build the wall without lifting the house off the foundation or having to remove siding or stucco and main floor framing rim joists to allow us to pour a concrete wall. When properly built and waterproofed, a wood foundation will perform as well and last as long as a concrete one. For this work, we first construct a temporary support wall to take the load of the house before we remove the foundation wall.
Failed wood foundations
Wood foundations can fail due to improper construction including undersized studs for the depth of the basement, wrong backfill materials, poor waterproofing or compromised studs due to electrical or plumbing holes. These problems can result in bowed or broken studs and leaking joints in the plywood. Wood foundation are fairly simple to pull down and replace as compared to trying to repair them. We replace them with a more robustly constructed wall, with a double damp proofing system and drainage rock for most of the backfill material. When properly built and waterproofed a wood foundation will perform as well and last as long as a concrete one.
All of the above repairs also require exterior excavation, waterproofing, weeping tile and a sump. In certain applications, it is possible to complete the waterproofing and repairs all from the interior.
We can usually provide a scope of work and pricing before we bring an engineer into the picture. If you decide to proceed with us, structural repairs require an engineer’s drawings to obtain permits and to ensure the repairs are properly completed.