Rotted subfloor, notched joist, & other problems that need repair

Discussion in 'General Flooring Discussion' started by zannej, Mar 18, 2017.

Help Support Flooring Forum by donating using the link above.
  1. Mar 18, 2017 #1

    zannej

    zannej

    zannej

    Professional Pro

    Joined:
    Jun 27, 2014
    Messages:
    913
    Likes Received:
    208
    Location:
    ,
    As some of you may have seen on sister forums, I'm living in a house that needs a lot of repairs/updates.

    I believe it was pretty much a DIY build back in the 30s or 40s. From what I can tell, the house originally consisted of a laundry room, one bathroom, one bedroom, the kitchen and a living room. I believe in 1947 (which I'm guessing from the 1-22-47 FAT scrawled on one of the joists of my room) they added two more bedrooms. I'm not sure when they added the greatroom and changed the entry point. Not much was done to code. It is a raised house made of wood, so the underside of the house is an open crawlspace. While trying to examine the plumbing, I noticed a few problems.

    1. Notched joist for tub P-trap and missing joist further down under my bathroom
    2. Water damaged subfloor under original bathroom shower

    I plan on keeping my existing cast-iron tub, but there is no vent on it's P-trap so I will eventually need to rectify that. When I do so (or even before I do so) I need to do something about the notched joist.

    This is a not-to-scale sketch of the house layout
    [​IMG]

    The areas with problems (that I've found thus far) are under the tub of B3 and the shower of B1. The floor joists run west to east, although under B3 there are lower beams running north to south and resting on the blocks.

    Notched joist on the left (and you can see that there is a joist that is straight up missing on the right)
    [​IMG]

    Damaged subfloor under original bathroom shower. Shower has no P-trap.
    [​IMG]
    This shower has not been used in over 16 years, but I wonder if the hot water leaked or is leaking because some of the damage seems to be around the hot water pipe.

    Fuzzier shot that shows more to the left of the drainpipe
    [​IMG]

    The "good" news is that I plan to gut that old bathroom, take down a small wall (non-load-bearing), and rip up the floors. But I'm now wondering if I will need to worry about the floor underneath the wall that I'm planning on leaving mostly intact.

    I will try to get more pictures later. When I was getting the latter ones, I got a nose full of dog tongue. But, I think that one is the most straight-forward fix: pull the subfloor and replace it. Then I need to figure out the best affordable flooring for the laundry room. I already know I want sheet vinyl for the bathrooms.

    The joist situation is something that I think will be tougher.

    What other pictures and info do you think is needed to help assess this situation?

    Just looking again, the notched joist is darker around the P-trap-- could that be water damage too? That tub has not been used in about 9 years.
     
    Last edited: Mar 18, 2017
  2. Mar 19, 2017 #2

    Ernesto

    Ernesto

    Ernesto

    Professional Pro

    Joined:
    Jun 25, 2011
    Messages:
    5,060
    Likes Received:
    757
    Location:
    , AZ
    Looks like you can sister that joist on each side or at least one side if the pipe is not sticking out to far. Then do a cross joist from side to side to strengthen it up.

    The leaks, got a moisture meter? Run it for awhile and stick it with a moisture meter before and after. Perhaps its condensation.
     
    zannej likes this.
  3. Mar 19, 2017 #3

    zannej

    zannej

    zannej

    Professional Pro

    Joined:
    Jun 27, 2014
    Messages:
    913
    Likes Received:
    208
    Location:
    ,
    So, I could sister a joist on the left and then maybe make a box with some shorter pieces on either side of the P-trap, right?

    Should I be concerned about the missing joist or do you think it's ok?

    I'm not sure why there would be condensation if the shower isn't in use. I'll have to get a closer look to see what the floor looks like under the other two tubs. Pretty sure the tub in B2 leaks because the floor of it cracked.

    Once I replace the floor in the B1/laundry area, I'm thinking I might just paint the floor rather than install flooring. I know there is paint specifically for floors, but I'm trying to figure out the best kind. Something easy to clean but that people won't be slipping on constantly-- but that won't be snagging things either.

    Edit: I forgot to mention that I found a tub overflow rough-in kit with a flexible green part that should allow it to be moved out of the joist at least a little. I'm hoping I can move it all the way out and then patch the notch. Would I need to sister the joist if I did the box to the next joist?
     
    Last edited: Mar 19, 2017
  4. Mar 20, 2017 #4

    Ernesto

    Ernesto

    Ernesto

    Professional Pro

    Joined:
    Jun 25, 2011
    Messages:
    5,060
    Likes Received:
    757
    Location:
    , AZ
    If you cut a joist like that it weakens the whole area. Sistering one side is good enough. If the joists are 16" I'd still do cross pieces with the weight of a tub full of water up there.

    Leaks could be old and already fixed or not, this is why you need to check before and after running it with a meter.
     
    zannej likes this.
  5. Mar 21, 2017 #5

    zannej

    zannej

    zannej

    Professional Pro

    Joined:
    Jun 27, 2014
    Messages:
    913
    Likes Received:
    208
    Location:
    ,
    Hmm. I don't have a moisture meter-- and I don't plan on keeping that shower. I'm going to rip it out and I was planning to replace the subfloor. There used to be parquet flooring throughout the house but when we got back from overseas the tenants had destroyed it (granted, wood is not a great idea for a bathroom & laundry room). I'm not going to keep the waterlines in that spot for the shower either.

    To give you a general idea, this is pretty much the current layout (I hid the walls of the shower & adjacent walls to make stuff visible):
    [​IMG]

    This is what I would like to do with the space:
    [​IMG]

    It would be nice to be able to walk in front of the washer and dryer while the doors are open-- can't do that currently. And the toilet is in a 23"W alcove.

    To be clear on the joist issue-- doing the box would not be sufficient? I would need to sister it on the other side?
     
    Nick likes this.
  6. May 22, 2017 #6

    eddie

    eddie

    eddie

    Member

    Joined:
    Dec 30, 2016
    Messages:
    9
    Likes Received:
    1
    Location:
    ,
    Tips to repair a water damaged subfloor, first remove the damaged floor material using a circular saw set to 1" depth to cut the flooring till you reach solid structural framing. Allow the area to dry thoroughly by proper ventilation. Add the supporting frame as needed and measure and cut the plywood. Fasten the new plywood, using galvanized 8d nails or deck screws. If need be, rent rapid-load screw gun if the area is large.

    Probably cutting the floor joist and box around the area. For deflection hangers and glue should hold. Long back, I had problems with the joist. I figured few cracks during a home renovation. I had to figure out the small cracks before they became too costly.
    For cracked joist, obtain two sturdy flat wood pieces to brace the sides of the cracked joist and prevent further crack.
     
  7. Jun 7, 2017 #7

    zannej

    zannej

    zannej

    Professional Pro

    Joined:
    Jun 27, 2014
    Messages:
    913
    Likes Received:
    208
    Location:
    ,
    I know this falls under more than just flooring. I showed my mother some photos of the back door & she realized how badly it needed to be replaced and it just so happened that Lowes was having a big sale on doors AND they extended their military discounts. So, she gets an additional 10% off.

    So we got a prehung back door with brickmould as well as the interior prehung door for what will be the new bathroom.

    Now I'm trying to figure out the best way to deal with the floor directly under the door. I don't know if there was an actual subsill or sill or whatever. I just know the wood is rotted and the edge of the floor sinks under the threshold.

    There used to be stairs here that went up to just below the lip of the sill (is that a sill?) but the siding people broke them and didn't replace them so we have cinderblocks piled up.

    The computer chassis is used to prop the door closed because it won't stay shut (probably my fault for using expanding foam in the cracks around the door-- I think I used stuff that expanded too much and I believe it warped the frame a bit).
    [​IMG]

    There used to be parquet flooring back there but the tenants destroyed it (and removed the steel 6 panel door-- replacing it with a crappy wood door that has rotted). We had cheap sheet vinyl put in at one point, but the door scraped it and tore it up.

    Here is a closeup of the rotted wood under the threshold. I can't tell if it is some piece of wood under there or if it is the edge of the plywood that has swollen up and cracked/split.
    [​IMG]
    [​IMG]

    And from the inside:
    [​IMG]

    I'm thinking of getting a PVC sloped sill pan that will direct moisture out. But I'm trying to figure out the right size for it and exactly where to put it and if I need to build up anything underneath. I wonder if I should just have a deeper threshold than that-- one that directs water out as well.

    I'm debating whether to just fix the floor near the door (with appropriate thickness plywood) or if I should wait until I'm doing the entire floor. I'm pretty sure all of it needs to be gutted.
     
  8. Jun 7, 2017 #8

    highup

    highup

    highup

    Professional Pro

    Joined:
    Mar 6, 2011
    Messages:
    6,917
    Likes Received:
    1,259
    Location:
    ,
    This last photo from the inside looking out tells me you're going to have some bad looking wood under that threshold.
    I'm not sure what a vinyl sill pan will do since water shouldn't get in there in the first place. When fixed, I'd add a storm door since it looks like wind blown rain hits the door.
     
    zannej likes this.
  9. Jun 8, 2017 #9

    zannej

    zannej

    zannej

    Professional Pro

    Joined:
    Jun 27, 2014
    Messages:
    913
    Likes Received:
    208
    Location:
    ,
    Well, after measuring the height of the header and talking to Neal over at the houserepair forum, he thinks there was originally a 78" tall door and an 80" was put in and that instead of raising the header, the original threshold/sill was cut out so that the door sits on the subfloor. It would explain why the door scraped the sheet vinyl up when swinging in.

    It doesn't help that the header is an inch lower on one side. So, I'm going to have to raise the header and install a subsill or sill underneath. Since I don't know what type of flooring I will use for the finished layer, I'm trying to figure out just how high to build the sill up. And I need to look at the threshold that came with the door so I can figure out how much of a bump up it will be.

    I want to put a storm door up, but I'll need to figure out a way to accommodate the cat door. I'd either have to get one with an opening so the cats could get through to the cat door. I know they sell them with pet doors in them, but I'd have to figure out how the cats would get though both doors without getting confused. It already took one of my cats 2 years to figure out how to use the cat door to go out (and then 3 weeks more to figure out how to get back in) with the existing cat door.

    And I still haven't decided if I should just take care of the floor closest to the door first and then do the rest later or if I should do the entire room in one go (leaving the bathroom for later). Then there is the question of what to do with the finished floor. I'm trying to decide between LVP, LVT, and sheet vinyl. I'm concerned the sheet vinyl will tear when moving the appliances. But I imagine if it would tear the sheet it might gouge the LVP or LVT as well. (Note to self: Learn better appliance moving techniques).

    And I might need to figure out how to add a floor drain for the washer (and find one of those pans with a drain that goes under it).
     
  10. Jun 8, 2017 #10

    highup

    highup

    highup

    Professional Pro

    Joined:
    Mar 6, 2011
    Messages:
    6,917
    Likes Received:
    1,259
    Location:
    ,
    Be sure to hang the new door with clearance to avoid any more "scraping" issues. Be sure to include the thickness of any potential backer board and tile thickness, plus a possible entry mat.
    Or in the case of a vinyl entry material, to include the thickness of an underlayment if needed and an entry mat. Just take time to weigh a future entry surface finished height.
    Is there another side of the house that a cat door could be installed that gets less weather? That side of the house seems to take quite a beating.
     
    zannej likes this.
  11. Jun 8, 2017 #11

    highup

    highup

    highup

    Professional Pro

    Joined:
    Mar 6, 2011
    Messages:
    6,917
    Likes Received:
    1,259
    Location:
    ,
    Be sure to hang the new door with clearance to avoid any more "scraping" issues. Be sure to include the thickness of any potential backer board and tile thickness, plus a possible entry mat.
    Or in the case of a vinyl entry material, to include the thickness of an underlayment if needed and an entry mat. Just take time to weigh a future entry surface finished height.
    Is there another side of the house that a cat door could be installed that gets less weather? That side of the house seems to take quite a beating.
     
    zannej likes this.
  12. Jun 8, 2017 #12

    zannej

    zannej

    zannej

    Professional Pro

    Joined:
    Jun 27, 2014
    Messages:
    913
    Likes Received:
    208
    Location:
    ,
    I'm thinking of raising the door threshold up at least 3/4". Or should it be an inch? I don't know the standard height from that from the subfloor.

    Unfortunately, this is the only place where we could put the cat door. The cats don't go to the front so they wouldn't use the door there. And the sliding door on the house is on a room the cats aren't allowed in.

    I'm wondering if I could build out a small landing and put an awning up over it to give that door a little more protection. I wonder if a screen door with metal/plastic section toward the bottom would help at all.
     
  13. Jun 9, 2017 #13

    highup

    highup

    highup

    Professional Pro

    Joined:
    Mar 6, 2011
    Messages:
    6,917
    Likes Received:
    1,259
    Location:
    ,
    3/4" would probably work if the plywood repair/replacement is suitable enough to install vinyl flooring on. If that floor repair will still end up needing an additional underlayment to make it an acceptable surface, that would make the floor 3/8" or so taller. 3/4 - 3/8 means you now have the door clearance around 3/8" . That's barely enough for an entry rug to protect the floor if you plan to use one.
    Basically, I'd be sure of a choice for an entryway floor surface material, then make the door height work with that.
     
    zannej likes this.
  14. Jun 10, 2017 #14

    zannej

    zannej

    zannej

    Professional Pro

    Joined:
    Jun 27, 2014
    Messages:
    913
    Likes Received:
    208
    Location:
    ,
    Thanks! I'm sort of leaning toward vinyl sheet-- at least temporarily. I think it would be much easier to put the door higher and then build up the finished floor a bit if need be to match rather than having the door threshold too low. I could probably put in a small ramp if I did it about 7/8 or an inch higher and went with vinyl sheet. That would leave it open to remove the ramp and put in LVP later. Do you think that is high enough?

    I'm expecting to tear out the floor all the way down to the joists (since I noticed there is damage to the floor under the house and I know it is damaged on top as well-- floor had huge pits from water damage in the laundry room). The guy who installed the cheap vinyl sheet stuff poured some kind of white powder into the holes and put water on them but the stuff broke apart when we were moving the new washer and dryer in years later-- ripped the vinyl sheet too. It was so cheap the guy was able to tear it with his hands, but we weren't planning on it being the permanent flooring. We just needed something there so we didn't have bare plywood.

    I'm hoping that I'll be able to get the new floor to be level. Any recommendations on the best type of plywood to use for the subfloor?

    I want something that will hold up to a lot of traffic, dog claws, cat claws, moving furniture (which we really should be more careful about), dirt, etc. I also want something easy to install-- so I was thinking some kind of vinyl sheet that doesn't have to be glued down (except maybe with that tape used for edges).

    I'm also trying to figure out if a screen door that has a solid bottom half would work instead of a storm door for giving a little more protection. I want to take one and cut a hole just large enough to give clearance for the swing of the cat door and allow the cats and the little dog to get through.

    Repairs are going to have to wait a little until after my ankle heals enough for me to be back on my feet.
     
  15. Jun 10, 2017 #15

    Nick

    Nick

    Nick

    Administrator Staff Member Admin Moderator

    Joined:
    Jan 31, 2010
    Messages:
    9,639
    Likes Received:
    1,532
    Location:
    , New Jersey
    Birch Ply. If you have to move anything heavy like the fridge , spray some Windex behind the wheels . It will slide like it is on ice .

    Don't like Vinyl. How about some engendered Hardwood ?
     
    zannej likes this.
  16. Jun 10, 2017 #16

    zannej

    zannej

    zannej

    Professional Pro

    Joined:
    Jun 27, 2014
    Messages:
    913
    Likes Received:
    208
    Location:
    ,
    I'm generally moving things like the washer and dryer (which don't have wheels). Since it is going to be the area with the washer and dryer, I want a floor that can handle getting wet in case there are any mishaps. I'm going to get new hoses for the washing machine just in case the old ones are anywhere near breaking.

    I do really like the vinyl plank and vinyl tile. The sheet vinyl isn't so bad if I can find good quality stuff that is durable. The bathroom and laundry area are fairly simple shapes so it won't be as difficult as it was for my bathroom.
     
  17. Jun 10, 2017 #17

    highup

    highup

    highup

    Professional Pro

    Joined:
    Mar 6, 2011
    Messages:
    6,917
    Likes Received:
    1,259
    Location:
    ,
    If it's just this entry, and possibly temporary, we're talking about a small piece. You can get good prices and good quality on vinyl remnants. If after the door was installed you had 3/4 of an inch clearance, that would probably be plenty. It would allow an entry mat and still have clearance.
    If at a later date you installed ceramic or stone, you might need to build the surface higher with backer board and the the tile thickness. So just be sure of the height or clearance you will most likely use as a permanent installation.
    Vinyl can be quite durable and cost per square foot or square yard isn't really an issue since the area is small.

    As far as plywood for the subfloor, I don't think I'd go as far as marine or especially not any sort of treated plywood. Fumes from treated plywood might eventually bleed up into the vinyl.
    Use a good quality plywood. AC or CCPTS not CD. CCPTS has no void in it's inner cores. AC has a better surface. It may have small voids but where I buy plywood, voids are small and rare............ your mileage may vary.
    Nick mentioned birch, but on the west coast we don't see any birch unless it's underlayment plywood made specifically for flooring underlayment. Subfloor plywood here is usually fir.
    There are some pretty tough vinyl products out there, even vinyl tiles. Again, since it's a small area, even high end expensive materials won't break the bank.

    Screen door with the solid bottom is a good idea. Maybe two cat doors in tandem?
     
    Last edited: Jun 10, 2017
    zannej likes this.
  18. Jun 11, 2017 #18

    zannej

    zannej

    zannej

    Professional Pro

    Joined:
    Jun 27, 2014
    Messages:
    913
    Likes Received:
    208
    Location:
    ,
    To clarify: The finished floor (vinyl sheet) might be temporary-- but I want the subfloor to be permanent. I'm also considering painting the floor. I want the subfloor to withstand moisture and heavy weight. I want the finished floor to withstand claws, foot traffic, dragging stuff, etc.

    I think that I will need to replace the whole floor near the back door and in that entire room.
    [​IMG]

    I'm going to have to tear down the wall from the start of the little door and then the perpendicular interior wall and gut that little useless bathroom.

    Here is a sketch with rough measurements of the area.
    [​IMG]
    I have it at this orientation because the top is to the North. The measurements are all rough ones.

    Eventually I intend to replace all of the floor because they don't make materials quite the same thickness as they used to. I also noted that the floor slants down to the left when I put a level on it in front of the door. Not sure if that is from settling or if it is because of damage or a combination of both. Is that something I could fix with shims of some sort on the joists when laying the new subfloor?

    Anyway, facing the exterior door from the inside, the room would be about 122.25"W x 94.5"L. So it's not really a small space for the whole room. But just in front of the door is 46"W x 94.5"L (to the opposite wall). So, I could probably use 4'x8' boards (if they sell them).

    On the vinyl scraps, I actually have some scraps left over from my bathroom that I might be able to use on the area in front of the door temporarily.

    1. Would I do the floor in 2 layers like the floor in my bathroom? They did a bottom layer, then a moisture barrier with another layer of plywood on top. (It actually saved the subfloor from rotting when there was water damage to the top layer that turned to mud-- happened in the adjacent bathroom with only one layer & toilet fell through the floor with my brother on it). Or would I just use a single thick piece of plywood?

    2. Would fumes from the treated wood discolor or damage the vinyl or just give it an unpleasant odor?

    3. If I got treated and then painted the top with something, could it lock in the fumes so it wouldn't transfer to the vinyl?

    4. Do you think bumping the threshold (and header for the door) up an 1" would be sufficient to allow for vinyl plank or tile with built-in underlayment (or some sort of underlayment if it allows) plus a floor mat? Or should I go for 1.5" or 2"?

    5. Would 3/4" for the subfloor be thick enough (I need to measure the distance of the joists-- not sure if they are more than 24" apart or not but I suspect they could be). I'm leaning toward 7/8" to 1" (if they make those thicknesses) because the floor will be supporting heavy appliances & a bathtub. I'll probably reinforce the joists under those areas as well.

    6. Would it be better for me to see if they have 4'x4' subfloor panels to make it easier to transport and move around?

    I saw a website listing plywood types and CDX and Sturd-i-floor seemed good-- although the latter is not available in my local HD (HD sells it but just not to my area). Not sure on the CDX.

    I forgot to mention on the cat door thing-- I'm not sure if my cats could manage 2 doors in tandem. I couldn't use flaps on my litterboxes bc some of them are too dumb to use them-- they would pee right next to the litterbox instead-- and I have one that took 2 years to figure out how to go OUT the cat door but he still didn't know how to get back in through it for another 3 weeks. (He would stand at the back door yowling until I opened it-- I finally opened the flap while he was outside and got him to come through and he figured it out-- and this cat watched other cats use the door but couldn't figure it out himself). Meanwhile, another cat figured out how to unlock the cat door so she could go out. So, I've got some very smart kitties and some very dumb ones. It's the dumb ones I'm worried about.
     
    Last edited: Jun 11, 2017
  19. Jun 18, 2017 #19

    zannej

    zannej

    zannej

    Professional Pro

    Joined:
    Jun 27, 2014
    Messages:
    913
    Likes Received:
    208
    Location:
    ,
  20. Jun 19, 2017 #20

    highup

    highup

    highup

    Professional Pro

    Joined:
    Mar 6, 2011
    Messages:
    6,917
    Likes Received:
    1,259
    Location:
    ,
    I don't know enough about treated plywood or 2X material for the subfloor, but I think most of it has the ability to discolor the vinyl over time. I'd call the manufacturer first to see if they recommend it for an interior subfloor material. I know in Hawaii they use a lot of treated wood, but I'd make sure it's OK for use as a subfloor as far as vinyl goes. Call the manufacturer about a particular product that you may use.
     
    zannej likes this.

Share This Page