What is the best way to cut floor exactly along wall?

[Caulking-Gunn]

I'm dealing with a trailer house with about 15 feet of bad floor along one side. I recently replaced the floor in the water heater closet in that trailer, and used a wood chisel along the wall. Just that 30" closet took hours. I'm trying to find a better way. A circular saw cant get close enough. I tried an angle grinder with grinder wheel, which worked but filled the whole house with smoke and was real slow.

I do have access to one of those Multi Function oscillating tools from a friend. I've never used one of them, so I dont know if that would work, and of course I dont want to rip up the wall either. I did see about a

4inch circular saw blade at the hardware store, I was wondering if I could put one of those blades on my angle grinder and use that. But I thought I'd ask if anyone has a better idea.

The floor is made from 3/4" particle board, but will be replaced with

3/4" plywood. (treated plywood by the door, which is where the floors always go bad in these trailers). However this trailer had a roof leak (which is now repaired), so that is why there is such a large repair

The goal is to just remove 4" from the wall the entire length of the bad area, and put down the plywood. I want to get right up to the wall to remove all the bad flooring and so I have as much of the 2x8 joist exposed to fasten the new plywood. I may still add blocks of 2x4 between each joist so there is more to nail to.

Thanks

[Terry Coombs]

I've been down that road and what worked best for me was to cut the PB an inch and a half from the wall . Just use your skilsaw , let the short side of the sole plate ride on the baseboard as a guide . This leaves you with a lip to screw 2x4 blocking between joists to screw your new plywood to . BTW , I was a flooring installer , did all my own subfloor repairs because the carpenters didn't understand you either have to block the joints or offset layers . Oh and if you can , lift the threshold and go thru the doorway with new plywood . -- Snag

[Unquestionably Confused]

[snip]

How about making an auxiliary base for your saw with an angled piece of wood that would allow the blade (presuming right side) to sneak up on the wall at an angle, undercutting the particle board?

You could just screw on a piece of wood, close to the blade to tilt the blade off 90 degrees. Another thought would be a resale shop and drop $15-$20 on a used, beat to crap circular saw and do some alterations on the base to get you even closeer.

With the saw set for maximum cutting depth, you should be able to get a LOT closer to the wall than 4".

Also, when you put the new subfloor in, use screws to fasten it to the joists, not nails.

[nestork]

The saw that will come closest to your wall would be a toe kick saw.

'Crain Toe Kick Saw 795'

Toe kick saws are used to cut through the underlayment when replacing the flooring in kitchens. In that case, the underlayment goes UNDER the kitchen cabinets, and if the old flooring was glued down, you have the daunting task of removing the old adhesive from the old underlayment. A far better option is to cut through the underlayment right in front of the cabinet and replace that underlayment. That way, you have a new and clean surface on which to install your new flooring. Most toe kick saws have a fixed cutting depth of 3/4 inch. If you want a shallower kerf, you put a piece of plywood or something down and run the saw over that plywood. Also, most toe kick saws will cut almost flush with the front of the toe kick; maybe a 32nd of an inch in front of the toe kick or something like that.

You can buy toe kick saws cheap from Harbour Freight, or you can rent them at any tool rental shop. I would try Home Depot tool rentals, or phone any retail carpet or flooring store and ask to talk to their Installations Manager. The Installations Manager would know which places in your area will sell flooring installation supplies, and which of those places would rent tools like a toe kick saw.

[Caulking-Gunn]

Now this does look like a handy tool, and made for exactly what I'm doing. But for one job. I'll rent it. That's pretty pricey. If I was in business, I might buy one.

This may help in the one place I need to go under an inner wall too. I dont want to remove the wall, so the thought is to cut it on both sides, and knock out the remains under the wall with hammer and chisel, then use a sawsall to cut off any nails on the bottom of the wall. With this tool I can cut close and wont have as much to bust out under the 3" thick wall, because that is all it is in these trailers. The trick will be to get the plywood under the wall, but these trailer homes always put down the particle board, then cover the entire floor with vinyl flooring, BEFORE building the walls. That extra 1/16th of an inch should help me get the plywood under it.

I'm putting 2x4 blocking under all joints, and will cover that entire part of the trailer with an extra half inch of plywood over tbe top. The half inch plywood is actually a little cheaper than the 3/16" underlayment. Even though the floor will be a half inch higher than the rest of the home, I figure the floor will be much stronger. Particularly where the existing particle board will remain.

It seems that one of the top reasons people junk trailer homes is because the floors give out. I know one guy who was very overweight, who almost every week put his foot thru the floor of an older trailer, and more than one chair leg went thru. But that part that made me laugh, is that both legs on the head end of his bed went thru one night. He would not admit it, but I think he and his wife were in the middle of some "hot action". I got tired of him calling me to help fix his floor, which in his case meant putting in a 16" piece of plywood. And the next week he'd break thru right next to the patch. I finally convinced him to cover all the floors in the whole trailer with 1/2" plywood, which was a lot easier than patching it all the time.

Anyhow, thanks for the tip. I did not know they made such a tool.

[dadiOH]

I'm confused...you want to remove a 4" strip but you say a circular saw can't get close enough. Man, that must be some whopping big saw you have, I've never seen one that couldn't cut 4" away from a wall; how close can you cut if you turn the saw 180 degrees and go in the other direction?

Assuming you *can* get close enough, just set the depth of cut = floor thicknes and cut away; use a prybar to lever out the cut off if there are nails holding it down. Now, you won't be able to cut all he way to both walls that are at 90degrees to what you want to remove but you could use a chisel for that...or angle a saber saw...or your oscillating tool (although cutting much wood with them is a chore).

[trader_4]

+1

That's exactly what I thought too. I've used a circular saw to cut plywood up against a wall and the typical 7" circular saw can get a lot closer to a wall than 4". Probably less than an inch, if I remember correctly. Maybe the 4" was mistyped and he meant something else?

The only problem with the circular saw is you can't get all the way into corners.

[Robert Green]

Good idea - they're cheap enough at HF, though, considering the cost of renting a toe-kick saw.

I remember how surprised I was when I saw a pro paperhanger go through a box of 100 razor blades for a two room job. But I also learned how important sharp tools are to getting the job done quickly and professionally. I just wish I could get the hang of sharpening drill bits. )-: The cutting lip of a Foerstner bit is easy enough to sharpen, twist drills, not so much, at least for me. Maybe there's a secret someone knows . . .

[HerHusband]

A reciprocating saw with a 6" blade would easily let you cut right up to the base of the wall. You would just have to hold it at an angle to control the cutting depth so you don't cut into the floor joists. It can be a little tricky to start the cut, especially in the corners, but it's doable.

I've made cuts like that several times without any problems. If you take your time, you can even cut away a top layer of plywood from two layers without damaging the bottom layer. Better to cut a little shy and clean it up with a knife or chisel than damage the structure underneath.

I would probably take it back 8-12" from the wall to have room to add blocking between the joists (at the wall, and at the joint in the flooring).

Anthony Watson

[Robert Green]

You must have the steadiest hands in the world. I don't think I could hold a sawzall steady enough to control the depth of cut unless I used some sort of long guide rod along the wall for the saw to "ride on." But then again I nearly failed freehand drawing at my tech HS.

I am interested in whether the OP's multi-function tool works out for this job. So far, mine's only been useful to remove lineoleum that was glued down with something that ossified into some sort of super-substance. Unfortunately I got the MFT when there was only a few square feet left to remove. D'oh.

[nestork]

Why settle for ordinary pressure treated plywood when you can use PWF plywood for the entrance? PWF plywood is plywood meant to be used when building "Permanent Wood Foundations", or houses that have wood walls for their basements instead of concrete walls. PWF plywood is like pressure treated plywood on steroids, being much more heavily pressure treated than your run of the mill pressure treated plywood. You can also buy end cut preservative for PWF plywood too, which has more of the active ingredient in it (copper naphthenate, I expect) than regular end cut preservative.

'Canadian Plywood Associati>

If you're going to be removing rotted particle board under the exterior walls, then I'd recommend you break the length of the job into 4 foot long sections, and do every 2nd section at a time. That way, the sections that are still in place will support that exterior wall while you're removing any rotted particle board from under it. You can still do all the cutting at once, but I'd be concerned that if you removed all the particle board subflooring from under an exterior wall, that wall will sag and you may end up with cracked drywall joints, broken windows, a door that won't open or close and all the other things that can result from building movement. By doing the job in pieces, you can avoid the wall sagging on you.

[HerHusband]

Bobby,

I hear ya, I'm horrible at freehand work myself. :)

Maybe I've practiced more than I care to admit, but it's not as hard as it sounds. The blade will tend to follow the bottom plate of the wall, and you can rest the foot of the saw on the floor as you cut. All you really need to worry about is holding the saw at the right angle to control the depth of cut. If you can find a blade that is wider (i.e. a demolition blade), it won't flex as much and will be easier to control.

I've done the same thing with a jig saw when I had no other choice, but the results weren't pretty. The reciprocating saw is much easier to control.

Actually, I had to replace a section of the subfloor in our old mobile home about 12 years ago due to water damage from a leaky washing machine. I didn't have many power tools back then so I simply used a handsaw to cut away the floor along the wall. Surprisingly it wasn't as much work as I thought it would be. The hardest part is starting the cut. I basically cut the open area between joists, then cleaned up the area over each joist with a utility knife and/or chisel.

For the second cut 6-12" from the wall, I would switch to a circular saw and a straight edge. Once you set the depth of cut, it's a no brainer.

Unfortunately, I do not own a multi-function tool, but when I've seen them used on TV shows they seem like they cut rather slow. That would be great for precision work, but I would think it would take forever to cut

15 feet with one. Hopefully the original poster can let us know how it works out.

Anthony Watson

[HerHusband]

Pressure treated plywood can't hurt, but it would be smarter to fix the leaky door situation. Adding a storm door to the exterior helps a lot when you don't have any roof overhang (typical on mobile homes). If you have to replace the door frame, install a Jamsill pan to direct any water to the outside of the building.

I suspect the original poster is doing more of a "patch" job, cutting up to the wall framing, but leaving the strip of particle board under the wall plates. That's the approach I used with our old mobile home because of the vinyl covered sheetrock. It's not the best approach, but most mobile homes don't have the best construction anyway.

Anthony Watson

[Robert Green]

Arthritic hands and a saw that's probably way more powerful and bigger than I really need would probably preclude my using my sawzall that way. As for following a line freehand with a jig saw, they call it that because in my hands it dances a jig around the line. (-:

[Robert Green]

I suppose I should cast about on YouTube looking for ideas about using the MFT. As I recall, it didn't come with much in the way of instructions. Thanks.

[Rory D. Dimov]

replying to dadiOH, Rory D. Dimov wrote: His issue is not the cut 4" from the wall it is how to cut the subflooring right next to the wall so that 4" strip can be removed. Because this is in a trailer, when it was initially built the floor is laid down first and then all walls are built on the floor. In order to remove a 4" strip of the floor right next to the wall you have to make two cuts, one 4" away from the wall parallel to the wall and the other right at the base of the wall, flush with the wall. No circular saw that I have ever seen can cut flush with a wall. I was using a multi-tool to do the flush cut but your right, it is a chore and I seemed to have worn mine out (replacing a lot of damaged flooring in a trailer).I used a circular saw and a jig saw where ever possible then the multi tool for the rest.

[terry]