Wood Foundation Inspections

About

While most traditional basement walls in Alberta are made from masonry materials such as concrete or stone, our property inspectors have encounter permanent wood foundations (PWFs) on several homes.  In the 1960s, pressure-treated wood was developed and it became possible for wood to be used in foundation walls without being prohibitively vulnerable to damage from insects and moisture.

wood foundation inspection alberta

Wood foundations may create a warmer basement in cold weather and may be more cost effective for isolated building sites where concrete is unavailable or would be expensive to transport.  However, wood in contact with soil is more prone to issues long term.  The primary issue is with moisture which causes the wood to rot, grow mould, and loose its strutural relability. Controlling the surface water around the foundation is critical if your home has a wood foundation.  If you are considering buying a house with a wood foundation in Alberta, you should have it analyzed by the FXC team of home inspectors & structural engineers to determine an estimated remaining service life, and be sure to correct all surface drainage issues before purchasing.

Common Wood Foundation Issues

  • Dampness. If dampness is present, its source should be identified. Dampness may be due to a rising water table, an inadequate drainage system, or inadequate damp-proofing. Water from an interior source, such as an air conditioner or a high-efficiency furnace, however, does not indicate a compromised PWF.
  • Exterior Wood Decay. Inspectors can check for exterior wood decay by probing the wall from the outside with a rod. It is usually adequate to probe once every 8 feet. If decayed wood is detected by probing, it is likely that decay exists elsewhere in the wall.
  • Interior Wood Decay. If the interior wall is not covered by drywall, it may be possible to inspect for wood decay below grade from the inside of the house.
  • Foundation Leakage. Evidence of foundation leakage may be discovered at butt joints where sealant may not have been used.
  • Buckling. Buckling can occur due to constant pressure over the course of years, or by the back-filling process.
  • Lack of a Moisture Barrier. Outside, a moisture barrier should be present and it should rise above grade.
  • Bowing of the Foundation Walls: especially the wall next to the basement stairs.