Subfloor Inspection
4 May 2012

Subfloor Inspection

Matt Neufeld

Your home is ready for back-fill once The City inspections have passed. Cedarglen will mark on the foundation walls both rough grade and final grade level from the plot plan to prevent any errors. The excavator will now truck in the clay fill that had been stockpiled from original excavations in the area. This fill is then spread around the foundation walls to the rough grade level set out in the plot plan and marked on the wall. Back-filling a basement is critical to the long-term stability of the foundation. For best practice Cedarglen compacts around the entire foundation walls limited only by access conditions. The soil is compacted using a compaction plate on the backhoe, in the garage area and the front and rear of the house to industry compaction levels. Even side yards are compacted with skid steers to prevent future settlement. The excavator will be back at the completion of the house to raise the soil level to final grade.

A framer then commences the construction of the homes sub-floor on top of the foundation walls. The subfloor material consists of engineered joists, beams, steel posts and sheathing. A third-party engineering firm provides an engineered plan to which the framers and City of Calgary building inspection follow to a concise manner. The framer first places the beam supported by the steel posts in the correct location. Then he fastens the joists in place with 19.2” approved spacing that Cedarglen demands which is above Alberta Building Code requirements. The framer must locate and provide clearance for plumbing entries, stairwell locations, and the engineered tall wall placement. It is also the framers responsibility to check all point loads set out in the building plan which are critical for a structurally sound home. Point loads are points in the subfloor which will take on a calculated load of the entire home. The framer will sheet the subfloor with ¾ inch tongue and groove sheathing. Cedarglen’s practice is to minimize floor squeaks through the combined use of an adhesive product and screws to fasten the floor sheathing. Subfloor adhesive glue is placed under the sheathing in order to bond the sheathing to the joists and then the framer screws the floor. Lastly, the framer will install the basement stairs as well as surrounding stairwell walls to the height of the basement floor.

Once the subfloor is completed, a Cedarglen supervisor performs a subfloor inspection. They check to ensure that the steel posts are level and in the correct location, the engineered flooring system is as per plan and point-loads are all accounted for. They will also ensure that stairs are placed correctly and well supported to the subfloor. Lastly, the supervisor ensures that basement windows and doors are square, level and as per the clients building plan.

Constructing a subfloor, although simple looking is worthy of a stringent inspection. A subfloor provides a solid base for your home.