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Swirl and broom finishes are typically specified for working surfaces of parking structures, parking lots, commercial pavements, or walkways. Unfortunately, the construction documents for many such projects specify unachievable F-numbers for slabs that are also specified to receive textured finishes. The article provides a bibliography of recommendations and requirements for slab F-numbers and finishes published in ACI documents, other industry resources, and sample project specifications, demonstrating that many conflicting requirements can negatively affect contractors charged with producing swirl and broom finishes.

Is Power Floating Required with a Broom Finish?: I’m working in an estimating department on a project for a bus depot and maintenance facility. The original contract specified a concrete slab with a coarse broom finish in the area where heavy buses are moving. After a bid was accepted, the floor finish was changed to a steel trowel finish, creating an additional work order. In the course of negotiations, the contractor stated that the original bid did not include power floating because it’s not required for a coarse broom finish. The contractor claimed that power floating is only required for a fine broom finish and that a coarse broom finish could be started almost immediately after placing. Our construction manager claims that power floating is necessary for early start of the rough broom finish and that ACI documents confirm his position. Is it possible to obtain information to support either of the claims? Temporarily Stopping Construction: An Update: The Concrete Q&A column in the April 2009 issue of CI responded to a question regarding protection of reinforcing bars extending out of concrete against corrosion when temporarily stopping construction. At the end of that column, we mentioned that there were probably several other options not mentioned in the article and asked CI readers to send us any particularly successful options that they had used. Gilbert Raynard, Managing Principal for the International Team at Read Jones Christoffersen Ltd. in Vancouver, BC, Canada, was kind enough to send us the following information.