Grace Lutheran Church, Fairgrove, MI

This project is an acid-stained concrete floor for the main sanctuary of a church in Fairgrove, a small town in the Thumb of Michigan. The concrete was poured in 1983 and then covered with carpet. Above left, you can see the rows of carpet glue used to hold down the seams of padding under the carpet. Above right is the concrete after stripping the glue and thoroughly cleaning.

The next two photos above show the concrete floor from the same perspective, after applying the stain, and then sealing. We used a base coat of gold stain, called “Buckwheat”, and then highlighted about 30% of the floor with a second coat of brown acid stain, called “Mission Brown”. The true color of the acid stains is revealed only after the clear sealer is applied.

Once we were done with the floor, the pews were reinstalled. The color turned out to be a perfect match for wood of the pews, although it would appear lighter (as in the previous two photos), and provide more contrast, if the overhead lighting was better. The current lighting in the church is relatively dim, and uses incandescent bulbs.

The next series of photos shows our work from another perspective. Above left, you can see the carpet used for the flooring of the sanctuary for 35 years (from 1983 to 2018). Above right is the concrete after the pews and carpeting were removed. There were a lot of other construction-related contaminants on the concrete than just the carpet glue, and we had to do a lot of cleaning.

Unless all of the carpet glue residue is removed from the pores of the concrete, it will show up during acid staining. Above, we used several different adhesive strippers, detergents, and hot water to remove the glue from the concrete without damaging the cement on the surface. Grinding would have been much quicker, but it would have removed cement along with the glue.

Despite the terrible condition of the concrete at the outset, the staining turned out magnificently, as you can see in the photo above left. We couldn’t remove all of the imperfections from the concrete slab, but were able to use our staining techniques to incorporate them into the overall patterning. Much of the floor ended up being covered, anyway, by the pews.

The last two before and after photos above show one other area of the floor that was particularly difficult to deal with - a large series of paint stains left by contractors spray painting metal pipe fittings on the floor. In the end, we were able to strip those paint stains completely so that they were no longer visible after acid-staining and sealing the concrete.