Cutting joist plumb in crawlspace

[Jeff Knecht]

Looking for technique to make a plumb cut, to head off joist in 24 in tall crawl, lying on back and can't see other side while I'm cutting. Like to use sawzaw. Thought I could screw in a steel brace on the blind side to use as guide. Anyone experienced this fun?

 

[Jeff Knecht]

By brace, I mean something like a mending plate or nail safety plate attached to blind side of joist, that the sawzaw blade could cut along.

 

[Sponsor]

 

[wwhitney]

My approach would be to sit crouched with my head in the joist bay, mark a line with a speed square, and cut most of it with a battery circular saw. You could clamp the speed square to the joist as a saw guide with the appropriate offset, if desired.

Then to finish the cut, take your pick: hand saw, reciprocating saw, jigsaw (which won't quite finish but will get closer than the circular saw, usually), oscillating saw.

If you're remodeling and have several cuts to do in one area, it's worth considering pulling up an area of subfloor so you can easily do the whole cut with a circular saw.

Cheers, Wayne

 

[Jeff Knecht]

My approach would be to sit crouched with my head in the joist bay, mark a line with a speed square, and cut most of it with a battery circular saw. You could clamp the speed square to the joist as a saw guide with the appropriate offset, if desired.

Then to finish the cut, take your pick: hand saw, reciprocating saw, jigsaw (which won't quite finish but will get closer than the circular saw, usually), oscillating saw.

If you're remodeling and have several cuts to do in one area, it's worth considering pulling up an area of subfloor so you can easily do the whole cut with a circular saw.

Cheers, Wayne

Mp

 

[Jeff Knecht]

Hi Watne, thanks for being there.
This bath remodel requires many different skills.

I want to cut as close to the drain pipe as possible without making the header any longer than necessary. On one side I can cut within 2 inches or so. But because joist is within 10 inches of wall, I can only cut from one side, and can't get any closer than the with of the motor and base. Don't think an oscillating tool wood work either. Trying to avoid removing the 2 layers of plywood from above but may have to.
I really was hoping that mounting a fence on the blind side would work.

 

[Jeff Knecht]

Forgot, where do I send your pay check?

 

[wwhitney]

The header lengths are the same wherever you cut the notched joist, they should be ~ 30.5". If you can get the two headers 16" o.c. or less, that's plenty close to each other, as it's the same your normal joist spacing.

You could try a jig saw, they are narrower and symmetric. You just need a good blade to cut through the 2x.

Cheers, Wayne

 

[Jeff Knecht]

The header lengths are the same wherever you cut the notched joist, they should be ~ 30.5". If you can get the two headers 16" o.c. or less, that's plenty close to each other, as it's the same your normal joist spacing.

You could try a jig saw, they are narrower and symmetric. You just need a good blade to cut through the 2x.

Cheers, Wayne

 

[Jeff Knecht]

I misspoke, meant to say joists or side trimmers.
I'm not going to sister the joists on either side of notched joists