2 Family Under Construction

On further reflection, when we sandwich the joists on both sides, through bolt and nail with 2X6’s, 2X8’s, 2X10’s, I believe we take a lot of bounce out of the floors.

Most often the old joists have been butchered over the years when gas lines were first run, when electrical was run etc.

Also, that system relies on the fact that the center, dipped portion of the joist is somewhere in the middle. So it would get a lot of meat on the ends, even if it grabbed little in the middle.

But usually the greatest “offset” is at the transition to a hallway, not in the middle.

Just thoughts.

Kyle,

That looks like an interesting system of sleeves. Thanks for the suggestion.

It sounds like they want to fabricate the materials custom fit for each job.

What we find in older houses is the joists are more random in width, one might be 2.75″, the next might be 4.25″ etc.

In a wider house, the sleeves may not be deep enough to grab meat on the joists.

Wonder how much they charge?

If I read you clearly, the gut reno has or will remove plaster and partition walls.

So you would be left with existing floor joists with sub and possible finish flooring.

Making floors flat, or additionally level is easier with a gut reno, in that the usual complications don’t apply (meeting existing finishes etc).

I can tell you definitively that making floors flat or level is not a function of “Installing support columns”.

Existing joists that are banana shaped over time will not willingly un-banana just because they are now supported.

Years ago we used steam boxes to bend the framing for wooden boats. The reason we used steam is because it was the only method that worked.

There are three methods for flattening or levelling floors in old houses.

Method 1 Replace joists with new steel channels into new pockets in the masonry. Advantages – perfectly straight, no waste on plywood subfloor, fireproof. Disadvantage – expensive for steel and new subfloor T&G plywood.

Method 2 “does not show signs of further movement, it may be simpler to just shim the floor, install new subfloor and hardwood.” Advantage – quick and dirty Disadvantages – not really straight, not really strong, thicker floor (lower ceiling)

Method 3 Sister and thru bolt existing joists with new 2X’s and new plywood sub-floor. Advantages – Allows some balance between flattening and levelling, strengthens floor, less costly Disadvantages – old subfloor must come up, requires carpenters with skills, less costly than #1, more costly than #2

Probably more than you wanted to know, but we have over 30 years experience doing this.

bruce at jerseydata.net

Leveling the floor by jacking up the building and installing new columns will likely cause lots of associated damage. i.e. cracked walls, doors that do not close, etc. If the building is solid and does not show signs of further movement, it may be simpler to just shim the floor, install new subfloor and hardwood.