We have always wanted wood flooring in our living / family and bedrooms. One day, while watching This Old House, we saw an episode that showed a brief clip of them installing end grain block flooring. They called it Cobblewood flooring. We searched the internet and found a lot of information and history about End Grain Block flooring or End Grain Wood flooring, also called parquet flooring. We saw everything from rustic installations to end grain parquet designs in palaces and mansions. It has been used as street pavers, factory flooring to support heavy machinery and reduce vibration. If you are going to do a project like this call us, we’ll tell you what we learned and maybe you will do better than we did. It is well worth your time to watch all of the videos that you can on planning, preparing, installing, finishing and maintaining this type of flooring. In our opinion, it is a low material cost hardwood flooring. But the labor is intense.
We chose 4×6, untreated pine posts as our material. Not very expensive. 10 foot pieces. Since we were trying to achieve an old, worn look, we were happy with the inconsistencies of the 4×6 pine post. If you want uniform sized blocks, you will need to run your posts through a thickness planer. Then all of your blocks will consistently be the same size and fit tight.
Grout or No Grout
We tried to make grout from the mounds of sawdust. I followed receipies from the internet but was NOT successful. We purchased a wood grout from Fortis Arbor. More on that later. You can butt the blocks together tighly and not use any grout. There are some great videos of a business in France or England using very fine sawdust from a floor sander and mixing some kind of liquid. I would think the expansion and conraction of the wood would cause the “grout” to crack and squeeze out.
Band saw or Miter Saw, benchtop sander or palm sander, heat gun, 4′ level, 8′ straight edge, router and possibly a router table if you want to use a router to ease the upper edges of the blocks. You’ll need eye and hearing protection. You’ll need some way to manage the dust from cutting the blocks and sanding. A notched trowl sized according to the adhesive manufacturer’s installation requirements.
Cutting the Blocks
The 4×6 pine posts were cut into 1/2 inch thick, 4×6 blocks using a Miter saw. I think it would be better to use a band saw, but I don’t have one. . I found that a 90 tooth, Thin Kerf blade on my 12″ miter saw made relatively smooth cuts. I wanted a thin kerf so I could limit the waste involved in this many cuts. Since we cut over 3,127 blocks, the pitch will build up on your saw blade. So keep it clean and it will cut better and the blade will stay cooler. I used a stop block to make my cuts consistent. I also checked the thickness of the blocks regularly with a micrometer(every 8-10 blocks). It’s really easy for that stop block to creep as you bump that large heavy post against it. If your blocks are different thicknesses, then your floor will be very uneven or lumpy.
Routing and Sanding the Blocks
The blocks were routed and sanded. We wanted the edges to rounded off. We took a palm sander, turned it upside down and clamped it into a Black and Decker Workmate. Next time, I’m getting a bench top sander.
Floor Prep – Leveling The Floor
We installed the block flooring on concrete. Of course the floor was not level so leveling the floor was the first step. I used a string and a pencil and a helper. Stretch the string from the center of the room to a point on the edge of the room. North for instance. Make a pencil mark at the point where the floor begins to be lower than the string. Them move clockwise a bit and repeat the process until you end up where you started. You will end up with odd shaped areas that need to be filled in. If you have and area that is too high you either have to build up the floor or grind it down. Since the pieces are short you can lay this flooring successfully on some slightly unlevel areas. This floor had been painted and glazed, therefore I used a Mapei primer before using the floor leveler. Just follow the directions on the package. If you have questions contact me or the Mapei folks.
Find the center of the room. Create your guide lines by making perpendicular lines in the center of the floor. You will work from this point. You will find your walls are not square so you need to create a layout that will be true to itself.
Next create guidelines to run the pattern you choose.
I would redraw the perpendicular lines often so that my rows of blocks were straight and parallel.
Laying Out The Blocks
Once the floor is level you need to determing what pattern you want to create and how much space between the blocks you desire. Remember that wood expands so leave at least a half an inch all aroud the room betwee blocks and the base plate of the framing or any solid wall.
We chose to overlap the blocks by one third. You could overlap by half, or do other patterns like herring bone, and other interlocking patterns.
Glue Down the Blocks
We used an adhesive that has a moisture barrier in it. They are expensive. Lumber Liquidators is where I purchase the adhesive. Bostitch makes one as well. Keep in mind that once you open the bucket of glue, it begins to dry and create a plug even if you reseal it tightly. So in effect a lot of adhesive gets wasted. If you can keep laying floor until the glue is gone, you’ll use less glue and save money. Follow directions on what kind of trowel to use and how deep the trowel point are. And this stuff gets everywhere no matter how careful you are.
Staining the Floor
Finishing and Grouting
We found a grout made especially for wood flooring by Flux Studios in Chicago. Their website click here. It is very dry compared to tile grout and requires a lot of work to press it down inbetween the blocks. The company that made the grout suggested that I finish the blocks before grouting. The reason was to be able to clean off the excess grout and haze.
We decided to use Minwax paste wax as our finish. We hand rubbed each coart and used a heat gun on low to melt the wax into the cracks and crevices of the blocks. And to remove haze from the wax. We put 2 coats of wax on before grouting. After grouting we put 2 more coats of wax. The first coat of wax gets soaked up quickly. Each susequent coat goes faster and is absorbed less.
We are happy with the results of this flooring project. It holds up to dog toenails, high heel shoes (no dents!), sliding chairs, students dropping trumpet cases ( teach music lessons in this room) and spills.
Got questions? Contact us.