Becker’s Blog #7: Men at Work

May 29, 2010

Before I talk about installation I’ll give a brief description on the shipping aspect. As mentioned, all the stone is being fabricated near Massa, Italy. The fabricator uses our shop drawings to detail each individual stone.

When a group of similar shaped stones are finished they are put into wooden crates packed with Styrofoam. When about 25 crates are finished (or 40,000 lbs worth of stone) the crates are loaded in a 20’ steel container and shipped across the Atlantic to the United States.

Click to enlarge

At this time the fabricator also prepares a packing list of all the stones that are in the container. The packing list identifies each stone and references our shop drawings so the installer knows exactly where each stone needs to go.

The container takes about two weeks from the Italian coast to reach the United States. In this particular case, with Sioux Falls, S.D. as the final destination, the container arrives in the port of Norfolk, Va., and is then sent by rail through Chicago to Omaha, Neb..

At Omaha, the container is opened (for the first time on U.S. soil) and inspected by the government. About half our containers receive a closer look, due to the high wood content of the crates; the inspectors are looking for bugs of any kind, especially beetles.

Sometimes these extra exams take a week or more. Like clockwork, the container you need the most is likely to be examined and delayed.

Once the container is cleared, it’s trucked to Sioux Falls. Total duration from Italian port to jobsite: four to five weeks. We’ll get a container every month and will utilize man power to keep up with the containers.

And now, some work-in-progress views at St. Joseph. You can click on any of the images for an enlarged view.

Here’s an aerial view of Sanctuary showing the (white) Calacatta Borghini treads and risers. Also shown is the (pink) Breccia Pernice and (grey) Bardiglio Imperial marbles at the altar platform.

The round platform is for the main altar. Note the four exposed concrete cubes. These support the 16’ solid marble columns. Our plan is to start installation in the round Sanctuary area and work our way out the front doors.

Al Snowaert is shown installing marble risers with copper wire. Our standard practice to installing risers is with #8 copper wire: the wire is epoxied into an anchor hole at the top of the riser, and then attached to the concrete structure.

The purpose for the anchor is so the riser will never come loose and move forward. The use of copper goes back more than a hundred years; it’s easy to bend and doesn’t corrode.

Once the riser is in place, there’s a void to fill. A mixture of Portland cement and sand is used.

As described to me 20 years ago this “dry tamp” has the consistency of wet snow. You can make a “mud ball” of the stuff, and it will hold its shape. The mud also supports the weight of the stone without sagging. (This painted a vivid description back then so I have used the snow comparison ever since.)

The mud is troweled smooth flush with the top of the riser. While the mud is wet the back of the stone tread is covered with thin-set mortar.

The purpose of the thinset is to create a bond between the stone and mud bed. The tread is set into the mud and tapped into place.

Here’s a cut-away view, via an end section of tread, riser, and mud bed.

With the altar steps completed, we started floor pavers. The install is similar to treads. The dry tamp mud is smoothed out to an approximate height and the floor paver, with the thinset applied to the back, is laid in the mud. The installer uses a non-marking mallet to tap the stone down to the correct elevation.

He must also hold the 1/16th joints between pieces. Many masonry companies can install vertical stone, but very few install horizontal stone in a mud bed.

The colors shown are (beige) Deskander, (brown) Giallo Reale Rosata, and (purple) Rosso Levanto.

Let me take a minute or two here to mention Al Snowaert, our foreman. Al has been installing stone for 30 years, and has been with us for the past 15. He’s run many of our large projects, and was a natural fit for this project.

Us office people push the paper and make the deals, but guys like Al make it happen in the field. Whether it is pushing the job to meet the schedule, showing a young installer some tricks of the trade, or explaining to the owners and architects what’s happening and why it’s happening this way (and when it will be done), the stone foremen are true ambassadors of the industry.

Thanks for reading,

Joe Becker
Twin City Tile and Marble Company
St. Paul, Minn.

Joe Becker has been in the natural-stone business for 26 years. He started with Cold Spring Granite as a draftsman and spent time in their stone installation and estimating departments. He is currently Vice President of St. Paul, Minn.-based Twin City Tile and Marble Company and oversees their stone operations.