The earliest PWF’s were constructed in the Prairies over 50 years ago and are still in use today. Click here for more information The most current guidance related to the design, construction, and specification of PWFs is found in the 2014 edition of CSA S406 ‘Specification of permanent wood foundations for housing and small buildings’. CWC also publishes ‘Permanent Wood Foundations’, which provides additional design guidance, selection tables, and construction details. Please note that this publication was produced in 1997 and conforms to CSA S406-92, which is not the most recent version of CSA S406. CWC will be releasing an updated version of ‘Permanent Wood Foundations’ in 2016. Please visit our webstore should you wish to purchase this or any other publications. Wood Preservation Canada is a member of the Canadian Wood Council, and their staff is very knowledgeable on pressure treated wood products. If your wood foundation has flooded, it is suggested to dry out the moist wood as quickly as possible and, if necessary, wash with soap and water (not bleach or oxidizing agents) to remove any sediment or fungi deposits.