Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Carpentry

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 09-26-2010, 02:10 PM   #1
Member
 
Join Date: Dec 2009
Location: San Francisco
Posts: 445
Rewards Points: 250
Default

Fix illegal notch in joist


There is a notch in the center of a 2x10 joist. Obviously that is illegal. It can only be notched on the outside 3rd.

So to fix it, I'm either going to sister another 2x10, or sandwich the joist between two 3/4" structural plywood.

My question is does the sister joist need to be the full span of the joist, or just in the center of the joist where the notch is.

acerunner is offline   Reply With Quote
Old 09-27-2010, 05:56 AM   #2
Member
 
Join Date: Dec 2008
Location: Wilmington, DE
Posts: 3,118
Rewards Points: 2,000
Default

Fix illegal notch in joist


The longer you span the notch, the better, but I would say at least 4' on either side. Glue/screw the pieces together.

Just Bill is offline   Reply With Quote
The Following User Says Thank You to Just Bill For This Useful Post:
acerunner (09-27-2010)
Old 09-27-2010, 11:30 AM   #3
Member
 
Join Date: Dec 2009
Location: San Francisco
Posts: 445
Rewards Points: 250
Default

Fix illegal notch in joist


thanks. ur right, longer would be better. I just worry I won't be able to squeeze it over the top plates on both ends.
acerunner is offline   Reply With Quote
Old 09-27-2010, 12:28 PM   #4
Registered User
 
Join Date: Mar 2009
Posts: 9,968
Rewards Points: 2,000
Default

Fix illegal notch in joist


Try a search here, I know I answered it has to be within the depth of the joist for a full sister. But your situation is different, just a scab each side, try to replace a chunk of solid lumber in the notch for compression with glue.

Gary
__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.
Gary in WA is offline   Reply With Quote
Old 09-29-2010, 09:57 AM   #5
Newbie
 
Join Date: Sep 2010
Posts: 4
Rewards Points: 10
Default

Fix illegal notch in joist


Quote:
Originally Posted by acerunner View Post
There is a notch in the center of a 2x10 joist. Obviously that is illegal. It can only be notched on the outside 3rd.

So to fix it, I'm either going to sister another 2x10, or sandwich the joist between two 3/4" structural plywood.

My question is does the sister joist need to be the full span of the joist, or just in the center of the joist where the notch is.
As an home inspector in Ontario I would question a repair/sister that was not full length; any other type of repiar would need a P Eng apporval.
FinalSay is offline   Reply With Quote
Old 09-29-2010, 11:16 AM   #6
Member
 
Join Date: Dec 2009
Location: San Francisco
Posts: 445
Rewards Points: 250
Default

Fix illegal notch in joist


Quote:
Originally Posted by FinalSay View Post
As an home inspector in Ontario I would question a repair/sister that was not full length; any other type of repiar would need a P Eng apporval.
is there a preference for full 2x10 sister, or plywood sandwich?
acerunner is offline   Reply With Quote
Old 09-29-2010, 02:49 PM   #7
Member
 
Tizzer's Avatar
 
Join Date: Jul 2010
Location: Richmond Va.
Posts: 312
Rewards Points: 250
Default

Fix illegal notch in joist


Quote:
Originally Posted by acerunner View Post
thanks. ur right, longer would be better. I just worry I won't be able to squeeze it over the top plates on both ends.
This joist is a ceiling joist? How's a home inspector going to see it covered in sheetrock?
If you feel the need to go wall to wall with the sister joist, cut it a couple or so inches short. Each end is still bearing, plug the notch with a chunk of wood as mentioned, and nail up the sister.
How big a notch is it?
Tizzer is offline   Reply With Quote
Old 09-29-2010, 04:41 PM   #8
Member
 
Join Date: Dec 2009
Location: San Francisco
Posts: 445
Rewards Points: 250
Default

Fix illegal notch in joist


Quote:
Originally Posted by Tizzer View Post
This joist is a ceiling joist? How's a home inspector going to see it covered in sheetrock?
If you feel the need to go wall to wall with the sister joist, cut it a couple or so inches short. Each end is still bearing, plug the notch with a chunk of wood as mentioned, and nail up the sister.
How big a notch is it?
It's a two story home. This is the joists in between. I am remodeling the lower floor so sheetrock is ripped out and I uncovered this error.

The notch is about 2" wide, 2" deep. Nothing was running through it, so not sure why it was notched to begin with.
acerunner is offline   Reply With Quote
Old 09-29-2010, 06:01 PM   #9
Civil Engineer
 
Join Date: Mar 2009
Location: Boston
Posts: 4,252
Rewards Points: 2,082
Default

Fix illegal notch in joist


The mechanics of a joist are that it carries approximately uniform load, meaning that the maximum moment occurs at the center of the joist, and drops off rapidly towards the supports, where there is zero moment. Therefore, there is no need to sister anything but approximately the middle 40 percent of the joist. Feel free to carry the sister joist all the way to the walls, but since the critical load is at the center of the joist, and shear at the ends almost never controls, it adds nothing to the ultimate capacity of the joist to carry the sister joist to the walls.

It is necessary to use a sufficient number of approved fasteners (typically common nails, but you can use approved screws or bolts as well) to insure that the moment is transferred from the damaged joist to the sister joist. Typically the pattern is a 16p common nail every six inches, with two on either end, assuming you cover the middle 40 percent of the joist, however this is simply standard practice, it is possible to compute the required nailing pattern based on the size of the joist, the type of wood, the load, and the type of fastener. I have never seen such a computation carried out for a sister project, although as I said in theory it can be done.

Daniel Holzman is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Supporting joist under cracked tile JT31 Building & Construction 2 08-26-2010 08:00 AM
Jacking and Sistering Floor Joist Captain.Sassy Building & Construction 17 08-11-2010 01:30 PM
Space between joist and beam on deck schveiguy Building & Construction 11 09-08-2009 09:15 AM
one rotted deck joist to replace, need advice dougq Building & Construction 10 07-07-2009 02:18 PM
replacing rotted sill plate and rim joist behind a deck ledger board tommyt Building & Construction 2 08-11-2008 07:38 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.