Concrete Casting News from the Hill and Griffith Company

The most commonly specified textures for precast include smooth, retarded and water-washed, form-lined, sand- or abrasive-blast, acid-etched or acid-washed, and tooled

Smooth texture, as the term implies, is an as-cast finish. This texture is a direct result of the quality of the formwork surface. It is the least aesthetically pleasing but the most economical of the surface textures, especially if the surface is to be field painted. Form defects and color non-uniformities are noticeable with this finish texture, air voids are normal, and surface crazing should be expected.

 

 This post is based on a review of the Precast Concrete Manufacturers Association of Texas' informative site and their Designer's Notebook Specification Guidance Part 2.

 

 

From our Dec 21. 2016 post,

 

"Amazon Book's summary (April 1, 1999), "Exactly what is a smooth-form finish? What is a rough-form finish? To what extent are bugholes, voids and fins acceptable in each type? This easy-to-use guide explains and illustrates the answers to these questions and, even more importantly, serves as the standard for the differences between as-cast structural concrete finishes. The succinct, yet thorough, text includes a glossary and a handy table on as-cast finishes. But the guide's Presentation Photos are what make it truly unique. Three sets of 6 different, full-scale photographs depict various as-cast finishes, with bugholes and voids ranging from 1/16" or less to 2" across. Attach a Presentation Photo to a bid or specification to show what surface finish is to be expected."

 

 

From our Mar 31, 2018 post,

 

"A word of warning, exposed concrete is the most difficult finish to achieve. A lot of designers think, "We're just going to cast the concrete, take the forms off and whatever is there, that's what we're going to take." Then, the first forms come off, they look at the concrete and say, "Oh my gosh, that's not what I wanted. What do I do now?" The only thing you can do is either paint it or tear it down and start over again. What I find that most designers want, most architects want when they say, "Exposed concrete", thinking it's not going to be architectural concrete, it's going to be exposed concrete, so it's going to be cheaper. They don't want exposed concrete. They want smooth as-cast architectural concrete, which is the most difficult finish to achieve. 

A word of warning, those of you that either design for exposed concrete or who have to build exposed concrete, what you are asking for and what you are going to receive may be two entirely different things. You have to understand the distinction between the two. 

Whenever somebody tells you that something is "Almost" like something else, you should usually run, don't walk. If exposed concrete is "Almost" like architectural concrete, that's a problem. Run away from those things, don't walk. If you want architectural concrete, specify architectural concrete."

From Precast Concrete Manufacturers Association of Texas:

2018 Best in Precast Concrete Award Program Opens