Sagging Joists


Old 04-05-07, 08:02 AM
Thread Starter
Join Date: Apr 2007
Location: Northeastern Ohio
Posts: 1
Sagging Joists

Hey out there,
I've got a century old farmhouse with 2x8 joists running up to 16' in some rooms on the first floor. These joists are mortised into oak beam which are pretty level due to the addition of posts. My idea is to rip out the old joists, bolt a ledger onto the beam and then tie the new 2x12 or 2x10 joists into the ledger using a shelf or hangers or both. I've put beams under one floor as an experiment but the mortised ends move up or down depending on which side of the room you're walking. Any feedback?-Angus Mc
Sponsored Links
Old 04-05-07, 07:24 PM
Join Date: Feb 2007
Posts: 94
I'm facing the same problem with my house, I was planning on sistering a new 2x to the existing one and using a double joist hanger on the ends. I never thought about the mortised end of the old 2x moving with it being nailed to the hanger.
Old 05-04-07, 10:11 PM
Join Date: May 2007
Posts: 11
Old 05-27-07, 10:57 PM
Join Date: Jan 2004
Location: Baltimore
Posts: 1,143
same situation here--107 year old house with rough cut 2x8 spanning 16'. Not sure what you mean about oak beam and posts? where are they? Sorry but am new to this. I don't think I have anything like that. I was just thinking of doing what I think you tried-putting beam (LVL perhaps) underneath joists with posts at ends. I don't understand how you are going to put 2x10 or 2x12 in? Isn't there only about 8" between your sill plate and bottom of subfloor (or in my case there is no subfloor-the hardwoods are right on joists!) since you have 2x8 now?

Old 05-28-07, 12:48 AM
Group Moderator
Join Date: Oct 2004
Location: WI/MN
Posts: 18,659
It would, as previously mentioned, be prudent to consult with an engineer on this.
Old 05-28-07, 07:26 AM
Join Date: Jan 2004
Location: Baltimore
Posts: 1,143
I already did. I had structural engineer out for something else-my now bankrupt contractor had footer for my addition poured about 3" too high so now we have to figure out how to lower floor so it will line up with my existing floor. My problem is really bouncy floor in old house (deflection) and anything you can do to shorten the span will decrease deflection. In my case, what I mentioned will work fine as a beam underneath the joists shortens the spans they have to carry. But I don't have the mortised beams and posts that were mentioned so I was just curious about that and what it looks like structurally. My joists rest on foundation (the are directly on the mortised stone foundation with no sill plate that I can see!) and carry simple span of about 16'. They didn't have pressure treated back 107 years ago I guess! So why don't the joists rot since they are sitting right on foundation? Maybe cause it is stone and not block or poured concrete and maybe doesn't have moisture problems associated with those types of foundations?


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes