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From Carpet to Diagonal Hardwood Flooring, Part 3

Keith Long
5 1 Chalk Line Unsanded

Hello, Keith Long here with Thunderheart Flooring to continue with the project we have been going through (see Part 1 and Part 2).

I like to build the majority of the floors I install from somewhere near the center, for a couple reasons. One, if a floor becomes water-damaged, it swells more on the tongue side, since there is more material there. Starting at or near the center of the scope of work decreases the likelihood of the floor buckling, as there are fewer rows of the tongues going the same direction. Two, it gives a person (or group of people) more options to rack out both directions, and fasten the floor two ways.

5 1 Chalk Line Unsanded

I glue down the first couple rows when starting from center. Since I want to glue down to a clean substrate, I need to know where that line will be so that I can sand that area. From the corner of the room, I measured out 2 feet and 4 feet in either direction along the walls. Then, I came into the field 2 feet and 4 feet from those points and marked cross points with a nail set that were 2 feet and 4 feet away from the corner. I tacked down the end of my chalk line with a nail set in the corner, lined up over the 2-foot and 4-foot marks in the field, and snapped it.

5 1 Chalk Line Sanded

Once I abraded the area where I wanted to glue my starter rows, I snapped my reference line once again. Since I had marked the 2-foot and 4-foot points in the field with a nail set, I could line up to them again, even after sanding the line off, without having to re-measure. I pulled out the backpack vacuum and cleaned everything in preparation for underlayment paper.

5 1 Underlayment

It has always amazed me how most of the board replacements, repairs or weaving into existing floors I perform following the work of other hardwood flooring contractors have either nothing between the hardwood and the subfloor, or a non-recommended product, such as red rosin paper. I like to use a “B” grade paper, such as this 30-30 paper that I got through The Masters Craft, a hardwood flooring distributor in the Denver area. I have been told that the “B” grade papers have the correct permeability rating to be suitable for between the subfloor and hardwood flooring.

I have used a lot of Aquabar “B”, made by Fortifiber, over the years. One of the other suppliers is supposed to carry it, but each time I call, those answering the phone to take orders there claim they don’t have it. I had been going to Home Depot to buy it. Lately, they have either been out of stock, or there are a couple of rolls there, that have been handled in a way that makes them look like they’ve been run through the mosh pit at a scream metal concert. They’re so torn and banged up that they don’t roll out and fasten down well if a person wants to snap chalk lines on top.

5 1 Mosh Pit Rolls New

The Masters Craft is the only entity between the manufacturer and my company for this 30-30 product. Their price is 20 percent less than Home Depot. Same “B” grade of paper, not dented up, costs less, and I’m treated with dignity and respect—to me, that’s a win-win-win-win. As a result, that’s who is getting my company’s business and money when I buy this product these days.

5 1 Papering

I left one row of flooring width on either side of the chalk line unpapered so I can use adhesive to the floor going either direction. It’s recommended to overlap 4 inches with each subsequent row of paper to maintain the correct permeability rating, so that’s what I do.

5 1 Floor Papered

Do you notice the orange tack stapler in the above photo? It takes T50 staples—that’s what I use to keep the paper down flat and in the same place. It makes it much easier to snap lines for the border than if the paper is just laid down loose. I install the rows of paper overlapping in the same direction as the rows of boards will be installed. That way, kicking boards in to be installed slide over where the rows of paper overlap, instead of tearing it.

5 1 Moisture Meter Setting

Now that the subfloor is sanded and vacuumed, I verified that the subfloor and the hardwood flooring were ready to install from a moisture standpoint. The above picture is my moisture meter’s setting (.70) for the specific gravity of OSB (Oriented Strand Board), which is what this subfloor is made from. This is because OSB is 70% as hard as ipé, which is the baseline wood this company has used to measure other woods against. Once set for density, so that I could get an accurate moisture reading, I documented 20 readings from the subfloor and averaged them.

5 1 Subfloor Reading


5 1 Hardwood Setting

Next, I changed the calibration of my moisture meter to the specific gravity of red oak (.63). As described in the above paragraph, this indicates to us that red oak is 63% as hard as ipé, and when set to .63 when calibrating on this meter, we will receive an accurate reading for red oak based on its density.

5 1 Hardwood Reading

To gain an accurate reading, either on the subfloor or hardwood flooring, it is recommended by the manufacturer to place a small amount of down pressure on the meter. Just 2 to 4 pounds of pressure, I’m not trying to drive the meter through the wood. Interestingly, the reading does change a bit between just resting on the board by itself, and applying a little downward pressure.

I documented 20 readings from the bundled red oak hardwood flooring and averaged them. The averages from the subfloor were 5.1 percent, and the averages from the hardwood flooring were 6.7 percent—a difference on average of 1.6 percentage points. For strip flooring such as this 2¼-inch-wide product, it is recommended that the difference in average moisture be no more than 4 percentage points between the subfloor and the hardwood flooring. So, we’re ready to proceed on this job site.

For plank (wider than 2¼ inch) flooring, it is recommended that the difference in average moisture be no more than 2 percentage points between the subfloor and the hardwood flooring. If the product on this job were plank flooring, since the difference was only 1.6 percent, we would still be ready to go.

Apologies, I didn’t take any photos on this particular job of measuring 8 inches away from the wall and snapping chalk lines around the perimeter of the room. I do this while the room is prepared and papered, while no wood has been brought in yet. These are reference lines to know how far both the near and far side the board has to go past on either end of each row. Once the field is installed, the 8 inches (3 inches for the select walnut, and 5 inches for the select red oak of the double-picture-frame border) from the wall is marked on top of the field that is running wild, and lines are snapped once again to know where to cut off for the border.

5 1 First Row Glued

Let’s meet up again next week to get rockin’ and rollin’ on the installation of this select-grade red oak, as we go through, step by step, what I do while installing, in what order and why.

I feel fortunate to work in some great homes here in the American West, and for getting to know many diverse and interesting people. I’ll leave you with a little comic relief from the bathroom of a home I recently worked in. Stay sharp, y’all!

5 1 Tp Humor

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