How to Fix a Rotting Bathroom Floor

If a toilet is allowed to leak for a long period of time onto the floor without being cleaned up, a rotted floor will usually result. The rotting bathroom floor surrounding the area will need to be taken up and replaced. This repair will also involve removing the toilet to take out the old section and install the new flooring. While it may be heavier as one unit, do not separate the tank from the bowl of a two-piece toilet when you repair the floor. This will protect against damaging spud gasket seals and tank bolts.

Things You'll Need

• Adjustable wrench
• Wet/dry vacuum
• Towel
• Putty knife
• Circular saw
• Utility saw
• Tape measure
• Plywood
• Hammer
• Nails
• Wood filler
• Drill
• Screws
• 2 replacement closet bolts
• Replacement wax ring

Instructions

1. Turn the water shut-off valve, located behind the toilet, all the way to the right.

2. Remove the lid from the toilet tank and place it in an area out of your way.

3. Flush the toilet, holding down the handle to allow the most amount of water to leave the tank. Vacuum out the remaining tank water, along with the water still in the bowl, using a wet/dry vacuum.

4. Remove the supply hose from the bottom of the tank, using an adjustable wrench. Pop the bolt caps from the toilet base, using a slotted screwdriver if necessary. Remove the nuts from the closet bolts, using an adjustable wrench.

5. Rock the bowl slightly in each direction, breaking the connection to the wax seal underneath and to the floor.

6. Straddle the bowl and grip on either side at the flat area behind the seat, directly forward of the tank. Lift the toilet up and off the closet bolts, using your leg strength, and carry the toilet into a nearby room, if space is confined in the bathroom. Place the toilet on the floor and set the toilet atop the towel.

7. Remove the bolts from the flange and scrape the remaining wax from the flange and from the bottom of the toilet.

8. Cut out the section of rotting floor, using a circular saw. Cut areas in corners and against the wall with a utility saw. Probe the affected area with a screwdriver, making certain that the damage did not spread to the subflooring, including the main beams, or joists. Measure the width and length of the cut area with a tape measure. Measure the depth of the cut area to obtain replacement material of the proper thickness.

9. Mark the area's dimensions on a sheet of plywood and cut out a replacement section from the plywood. Measure and cut out an opening for the closet flange within the plywood section. Cut a properly sized opening so the flange collar will rest on top of the plywood.

10. Cut the plywood into two pieces, passing through the center of the flange hole in the plywood with the cut.

11. Fit each half of the plywood into place on the floor, sliding them together, with the opening for the flange fitting around the flange and resting under the flange collar. Nail the plywood into place. Drill screws through the flange holes and into the plywood, securing the flange to the new floor.

12. Spread wood filler into the crevices between the new plywood and the old wood, using a putty knife. Sand the dried wood filler until it is completely smooth and even with the wood surfaces around it.

13. Install replacement bolts into the closet flange, with the threaded ends of the bolts up. Install washers on the bolts. Press a replacement wax ring on top of the flange.

14. Carefully lower the toilet into place on top of the flange and wax ring. Reconnect all the components of the toilet.

15. Turn the shut-off to the left, opening up the toilet's water supply.

16. Flush the toilet, and check around the toilet for any leaks.

References

• "Popular Mechanics Complete Home How-To"; Albert Jackson and David Day; 2001
• "Creative Homeowner Ultimate Guide To Plumbing"; Merle Henkenius; 2006