Over the last couple years, our bathroom developed a "soft spot" in the floor, right where you walk in. It was right in the middle of the doorway, and just over the threshold - so it was quite noticeable whenever you walked in or out. My wife wisely said "you should really fix that".
My initial suspicion was that the subfloor was just worn out. In a previous life, this bathroom was an outdoor porch. When we remodeled it 19 years ago, I didn't replace the subfloor (which my wife maintains was a mistake - she's probably right). So, I thought I'd cut out a chunk of the subfloor and put in a replacement and move on.
Weekend #1
I started by tapping on the floor to locate the floor joists, and then cutting a hole ...
No, that's not true. I started by making a trip to Sears to buy a couple saws. I haven't had a circular saw for a few years, and I needed a table saw both to make nice straight cuts on OSB and luan (and for lots of upcoming trim work). So, that came first, on a Saturday morning. I also stopped at Lowe's and bought a piece of 3/4" OSB and a piece of 1/4" luan. I had them cut both pieces in half, so I had two 4x4 pieces of each.
So. I started by tapping on the floor to locate the floor joists, and then cutting a hole between them (about 14 x 16) with my newly-acquired circular saw.
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| There's a hole in the floor! |
The first thing I noticed was that the subfloor was unexpectedly solid. And rather recent looking - as it "it's not the 50-year-old wood that I was expecting to find".
That's right - both of these floor joists had been severed and then supported with only a 2x4 underneath them. The ends of the 2x4 are well supported atop the foundation on both side. But, the 2x4 is lying on its side, with nothing supporting the middle of it. Of course it has sagged a bit over time. Sigh.
This was quite disheartening, and plenty enough a Saturday. I poked around a bit more on Sunday, trying to see how I could improve things. While I stared at the woodwork and considered my options, my wife looked up a number of Youtube videos. None of them gave me the answer I needed, but it turned out that I was able to use bits of a few videos during the following weekend.
Over the following week, I talked to a few men at church, and got some ideas. I also talked with my best friend (who used a week of his vacation to help me remodel the bathroom 19 years ago). Through this, I gathered a number of ideas. Coupled with some YouTube hints, it was time to attack the fix.
The next weekend's work on the floor started on my birthday, right after my radio died.
My approach was going to be:
No going back now.
So, now that I had located the floor joists, I expanded my hole by cutting 1" deep along the middle of the floor joists, and most of the way back to the door. I noticed that there was a slight gap between the joists and the floor, and my first thought was "SHIMS!!"
But then, I wondered why the shims were needed. As I stood on the floor and felt it move a little, I took a closer look at the floor joists.
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| Looks pretty OK from this angle. |
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| Uh oh - that looks suspicious. |
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| And that looks even more suspicious! |
That's right - both of these floor joists had been severed and then supported with only a 2x4 underneath them. The ends of the 2x4 are well supported atop the foundation on both side. But, the 2x4 is lying on its side, with nothing supporting the middle of it. Of course it has sagged a bit over time. Sigh.
This was quite disheartening, and plenty enough a Saturday. I poked around a bit more on Sunday, trying to see how I could improve things. While I stared at the woodwork and considered my options, my wife looked up a number of Youtube videos. None of them gave me the answer I needed, but it turned out that I was able to use bits of a few videos during the following weekend.
Over the following week, I talked to a few men at church, and got some ideas. I also talked with my best friend (who used a week of his vacation to help me remodel the bathroom 19 years ago). Through this, I gathered a number of ideas. Coupled with some YouTube hints, it was time to attack the fix.
Weekend #2
The next weekend's work on the floor started on my birthday, right after my radio died.
My approach was going to be:
- Remove the stubs of floor joist still attached to the beam (hooray for owning a reciprocating saw)
- Sister a new length of floor joist next to each of the severed joists, attached with carriage bolts
- Use joist hangers to attach the new sistered joists to the beam under the doorway
- Cut new piece of OSB to fit
- Cut new piece of luan to fit
- Use wood putty to fill any cracks and voids
- Finish installing the remainder of the vinyl tile to match the rest of the bathroom
I had stopped at Menards earlier in the week to purchase joist hangers and bolts - and some construction adhesive to keep adjoining pieces of wood from rubbing together and squeaking. So, I was ready to go!
First, I found a spare 2x8 in the garage and cut it in half, figuring that this would be enough support for what I was trying to accomplish.
I used a Sawz-All reciprocating saw to cut through the nails between the severed joist stubs and the beam they were attached to. For some reason, I thought this would be really hard - I think it took less than a minute in total. That's OK; most of the rest of the job ran consistently over estimate.
Then: I needed to make sure that the original floor joist was at the right height so that the floor would be solid and level. This is where YouTube came in handy. I had watched a video where a guy had used his automobile jack to hold a floor joist in place. So, I got a piece of OSB to place the jack on, and then I jacked up the first of the old joists until it was at the right height.
Then, I measured the vertical space for the new floor joist. It turns out I needed to rip 1/2" off of the length of it and notch out a corner to fit under the original door sill. I also drilled four 3/8" holes through it, which is where the carriage bolts would be placed:
With much trial and error, I placed the joist into place and got it also up on the jack so that it was tight.
When I made sure I had the fit right, I pulled it back out, put the joist hanger into place, replaced the joist, and then attached the joist hanger to the beam and to the joist. In the picture below, you can see why I quickly switched from nails to deck screws.
A quick note about the joist hangers. I wasn't sure what I'd need when I went to the Menards, so I bought a pair of joist hangers that could be used for anything from 2x6 to 2x12. They look like this:
It turns out that I needed close to 2x6 rather than 2x12. It also turns out that there was a slight gap between the old door sill and the beam beneath it. So, after measuring the appropriate length, I bent the "ears" and slid them between the sill and the beam. Unfortunately, they were too long - so out came the tin snips. I cut the ears so that only about 1-1/2" was sticking out past the bend. This turned out to be quite handy, as the joist hangers were then mostly self-supporting until they were actually fastened to the wood.
Next, I moved the jack to the other end of the new joist, and jacked it up tight against the floor. Then I used the handy Milwaukee heavy-duty right-angle drill to finish the bolt holes, drilling through original joist by starting in the 4 holes that I drilled in the new joist. I then started putting bolts in.
At this point, I realized that I bought bolts that were too short. Apparently 3-1/2" bolts aren't long enough to attach two floor joists together. Sigh. So, I had to run to the local hardware store for some 4" bolts. By the way, they were at least three times as expensive as the bolts I got at Menards - but it was an hour less of driving.
But, then, I had one of the two floor joists installed! It was certainly fun trying to tighten the nuts onto these bolts, especially the ones farthest from the door where my arms barely reached through the hole. It was also fun trying to finish drilling these holes, for the same reason. (There is a crawl space under the bathroom, but it's not the roomiest of workspaces - I avoid it whenever possible.)
The next joist repair went a little quicker - partly because I had a better idea of what I needed to so, and partly because I took the opportunity to employ a second jack so that I could support both ends of the work at the same time. Glad we have two vehicles!
Next, it was on to the replacing the flooring. My wife was studying the flooring that was installed atop the old door sill, and suggested that I remove that and put in one piece of subfloor to cover all of it. As usual, she was right, so that's what I did.
At this point, I'll stop and note that things started to make more sense here. This appears to be an original door sill for an door leading outside to the porch. I will also note that this door sill is sloped slightly (so that rain hitting it would run away from the house, apparently). That slope would make the next step very interesting.
First, I measured the opening, marked it off on a piece of OSB, and then broke out the table saw. I had bought a plywood blade for it (in addition to the ripping blade that it came with), so I installed that blade. My son-in-law helped me guide the OSB through the saw, including cutting the inside corners. Boy, I like this saw.
Next, I needed to bevel the underside of the OSB over where the door sill is. "Bevel." Hmm. Hey, my table saw supports beveled cuts! So, I did some measuring and figuring, and then I raised the saw blade all the way up, beveled it at about 4 degrees, and fed a test piece of OSB through on edge to bevel it away. After a couple tests, my son-in-law helped me guide the "real" piece of OSB through the saw to bevel it.
I knew that I'd need to do some sanding as well, because the saw blade only sticks up about 3", whereas I needed to bevel about 4-1/2" of wood.
So, I got out the belt sander with its old mostly-worn belt - and I sanded and sanded. And sanded. I didn't get particularly far.
My wife was headed to the mall with her mom later in the week, so I had her pick up some new sanding belts at Sears. I was ready to finish the floor during the next weekend!
Fixing the joists
First, I found a spare 2x8 in the garage and cut it in half, figuring that this would be enough support for what I was trying to accomplish.
I used a Sawz-All reciprocating saw to cut through the nails between the severed joist stubs and the beam they were attached to. For some reason, I thought this would be really hard - I think it took less than a minute in total. That's OK; most of the rest of the job ran consistently over estimate.
Then: I needed to make sure that the original floor joist was at the right height so that the floor would be solid and level. This is where YouTube came in handy. I had watched a video where a guy had used his automobile jack to hold a floor joist in place. So, I got a piece of OSB to place the jack on, and then I jacked up the first of the old joists until it was at the right height.
Then, I measured the vertical space for the new floor joist. It turns out I needed to rip 1/2" off of the length of it and notch out a corner to fit under the original door sill. I also drilled four 3/8" holes through it, which is where the carriage bolts would be placed:
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| The first of the support joists |
With much trial and error, I placed the joist into place and got it also up on the jack so that it was tight.
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| Trial fit of the first joist |
When I made sure I had the fit right, I pulled it back out, put the joist hanger into place, replaced the joist, and then attached the joist hanger to the beam and to the joist. In the picture below, you can see why I quickly switched from nails to deck screws.
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| Joist hanger in place |
A quick note about the joist hangers. I wasn't sure what I'd need when I went to the Menards, so I bought a pair of joist hangers that could be used for anything from 2x6 to 2x12. They look like this:
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| My, what big ears you have! (Picture credit: Menards.com, SKU 227-1549) |
It turns out that I needed close to 2x6 rather than 2x12. It also turns out that there was a slight gap between the old door sill and the beam beneath it. So, after measuring the appropriate length, I bent the "ears" and slid them between the sill and the beam. Unfortunately, they were too long - so out came the tin snips. I cut the ears so that only about 1-1/2" was sticking out past the bend. This turned out to be quite handy, as the joist hangers were then mostly self-supporting until they were actually fastened to the wood.
Next, I moved the jack to the other end of the new joist, and jacked it up tight against the floor. Then I used the handy Milwaukee heavy-duty right-angle drill to finish the bolt holes, drilling through original joist by starting in the 4 holes that I drilled in the new joist. I then started putting bolts in.
At this point, I realized that I bought bolts that were too short. Apparently 3-1/2" bolts aren't long enough to attach two floor joists together. Sigh. So, I had to run to the local hardware store for some 4" bolts. By the way, they were at least three times as expensive as the bolts I got at Menards - but it was an hour less of driving.
But, then, I had one of the two floor joists installed! It was certainly fun trying to tighten the nuts onto these bolts, especially the ones farthest from the door where my arms barely reached through the hole. It was also fun trying to finish drilling these holes, for the same reason. (There is a crawl space under the bathroom, but it's not the roomiest of workspaces - I avoid it whenever possible.)
The next joist repair went a little quicker - partly because I had a better idea of what I needed to so, and partly because I took the opportunity to employ a second jack so that I could support both ends of the work at the same time. Glad we have two vehicles!
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| The second floor joist installed, showing one of the bolts. |
OSB subfloor
Next, it was on to the replacing the flooring. My wife was studying the flooring that was installed atop the old door sill, and suggested that I remove that and put in one piece of subfloor to cover all of it. As usual, she was right, so that's what I did.
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| Old flooring removed from atop the original door sill. |
At this point, I'll stop and note that things started to make more sense here. This appears to be an original door sill for an door leading outside to the porch. I will also note that this door sill is sloped slightly (so that rain hitting it would run away from the house, apparently). That slope would make the next step very interesting.
First, I measured the opening, marked it off on a piece of OSB, and then broke out the table saw. I had bought a plywood blade for it (in addition to the ripping blade that it came with), so I installed that blade. My son-in-law helped me guide the OSB through the saw, including cutting the inside corners. Boy, I like this saw.
Next, I needed to bevel the underside of the OSB over where the door sill is. "Bevel." Hmm. Hey, my table saw supports beveled cuts! So, I did some measuring and figuring, and then I raised the saw blade all the way up, beveled it at about 4 degrees, and fed a test piece of OSB through on edge to bevel it away. After a couple tests, my son-in-law helped me guide the "real" piece of OSB through the saw to bevel it.
I knew that I'd need to do some sanding as well, because the saw blade only sticks up about 3", whereas I needed to bevel about 4-1/2" of wood.
So, I got out the belt sander with its old mostly-worn belt - and I sanded and sanded. And sanded. I didn't get particularly far.
My wife was headed to the mall with her mom later in the week, so I had her pick up some new sanding belts at Sears. I was ready to finish the floor during the next weekend!
Weekend #3
So, I sanded and sanded... And performed test fits. And sanded some more. And more test fits. The new 80-grit sanding belt really helped - I spent only about an hour trying to make this board fit. In the end, this is what I ended up with:
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| The piece of beveled OSB. |
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| A close-up of the beveled section. |
As I was considering installing it, my wife stood on the old door sill - and said "hey, this thing rocks." Sure enough, I watched it rock along its long axis as she moved her weight back and forth on it. I cut a piece of 2x6 to use as a support, got the jack back out, jacked up the block underneath the door sill, and then screwed the block to the beam:
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| Door (sill) stopper. |
I also installed a similar block in the space to the left, under the old floor - I jacked it up and screwed it in blind. And, I put about a dozen deck screws in the top of the sill, securing it to the beam.
Then, I put the OSB into place - after tracing its shape onto a piece of luan. I ran a few beads of glue on the sill and the joists to hopefully prevent future squeaking. Then, a dozen or more deck screws and it is there to stay.
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| Floor! |
Luan
Next, it was time for the luan. Since I had traced the shape of the OSB onto the luan, it was fairly easy to cut out using my RotoZip with its cutting wheel attachment. The first piece was a little too small, so I cut out a second piece that was a little larger. I laid it in place and felt around the edges to check how close I was on the depth.
It turned out that two of the edges were a little low - and the end farthest from the door was a little more than 1/16" too low. So, I shimmed that end up with layers of cardstock, gently ranging from 1 sheet to about 13 sheets thick. You can see the white cardstock peeking out at the edges of the luan here:
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| Luan getting ready to be nailed down. |
Wood Putty
After another trip to the hardware store to buy underlayment nails, I fastened the luan to the floor. I checked the depths again, and a couple edges were a little low after being nailed down - so I built them up with some wood putty. I also filled in all the cracks with putty so that the floor didn't have any gaps in it.
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| First application of wood putty |
Later that night (Sunday), I sanded the putty and then filled in a few voids, leaving it for its last sanding on Monday.
Tile
Most of the bathroom has already been covered with 12" square adhesive-backed vinyl tile; this was the last bit to complete.
So, Monday night, I did the last sanding on the wood putty. Then, I cleaned the floor three times to make sure it didn't have any dust or dirt on it. Next, I quickly laid down the 5 tiles that didn't have to be cut. Afterwards, I cut and placed the two pieces in the middle of the doorway edge, the larger of the two pieces next to the bathtub, and the piece that fit around the corner between the bathtub and the door. Then, I did some finagling with a paper template to get a rough outline of the piece that had to fit around the left side of the door frame (since there wasn't any clearance to slide the tile under it). After some trial and error (and a good deal of whittling), I got that piece in place - as well as the final piece at the corner of the bathtub.
I couldn't complete the floor, though, because there was a void in the original floor behind the door. I filled that with wood putty and left it for the next night.
The end results of Monday night are shown in this picture - you can see a tiny bit of wood putty peeking out from the door at the bottom right of the picture:
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| Almost done!! |
So, Tuesday night, I sanded the last bit of the wood putty. Then I cleaned the floor again, quickly cut and placed two pieces of tile ...
... and then had to figure out how to make the complicated cuts on the last tile. Again, at the other side of the door frame, there was no room to slide the tile underneath the frame. If I wanted it to look good, I was going to have to cut the tile to fit.
I taped a piece of paper to the floor, and then used a 12" strip of cut tile as a guide to transfer the contours of the wall and the door frame onto the piece of paper. I then cut out the paper to make a template:
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| Kinda looks like a state. Massachusetts? |
I flipped this paper over, taped it to a piece of tile, traced it with a pencil, and then cut and whittled it out piece by piece. I did about a dozen "test fit and re-whittle" iterations until the piece looked like this:
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| I'm surprised I survived the whittling session with zero blood loss. |
Here are a couple pictures of the final result in that corner.
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| Baseboard will cover up that dent in the wall there. |
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| The kitchen floor is a future project. :) |
And the end result:
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| The floor is done!! |
What's next?
The floor is done! Well, except for some grout (in the whole bathroom). And some baseboard trim. And finishing painting the walls around the bathtub. And figuring out something to do with the ceiling.
Epilogue: Tool Inventory
The following tools were used in this project, pretty much in this order:
- Craftsman circular saw (for cutting into the floor)
- Tape Measure
- Pencil
- Standard screwdriver (mainly for prying)
- Claw hammer
- DeWalt cordless drill and square drive bit (for deck screws)
- Milwaukee Sawz-All reciprocating saw (for cutting through nails)
- Needle-nose pliers (for pulling old luan staples)
- Two chisels (for removing stubborn bits of wood that the saws couldn't reach)
- DeWalt portable 10" table saw (for cutting/ripping 2x8s and cutting OSB)
- Milwaukee Heavy Duty Right-Angle Drill (for drilling 3/8" holes through joists)
- Two Toyota Sienna scissor jacks (from two Toyota Siennas, of course)
- Pliers and Tin Snips (for bending and cutting the joist hangers)
- Black&Decker adjustable-grip clamps (to hold the floor joists together)
- Craftsman ratchet with 9/16" socket, and Craftsman 9/16" box end wrench (for tightening the carriage bolts holding the floor joists together)
- Craftsman belt sander (for sanding the beveled edge of the OSB)
- Caulking gun (for applying the glue between the joists and the OSB)
- RotoZip with X-Wheel attachment and wood-cutting wheel (for cutting luan)
- 4" plastic putty knife (for applying wood putty)
- Hand sanding block (for sanding the wood putty)
- Stanley utility knife (for cutting the tile)
- 4 foot level (used as a straightedge when cutting the tile)
Thankfully, I already owned all of these tools - with the exception of the aforementioned circular saw and table saw.
