# joists are pulling away from sill plate



## Yodaman (Mar 9, 2015)

only the joist in pic 1 has me a little concerned, pretty common for joists to shrink and pull away from the beam or rim joist a little. Some of it may be seasonal due to moisture in the summer and dry in the winter. A furnace in the basement will dry things up in the winter and cause some shrinkage.

To add a little insurance and comfort you might want to add joist hanger bracket(s). This would require some blocking being lag screwed to the rim joist so the surface will match the ledger board and have a flat surface to attach the hanger bracket to. Or a simpler remedy would be to add angle brackets, one on each side of the joists.
Option 1 would be my preference.


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## andrewjs18 (Dec 14, 2011)

Yodaman said:


> only the joist in pic 1 has me a little concerned, pretty common for joists to shrink and pull away from the beam or rim joist a little. Some of it may be seasonal due to moisture in the summer and dry in the winter. A furnace in the basement will dry things up in the winter and cause some shrinkage.
> 
> To add a little insurance and comfort you might want to add joist hanger bracket(s). This would require some blocking being lag screwed to the rim joist so the surface will match the ledger board and have a flat surface to attach the hanger bracket to. Or a simpler remedy would be to add angle brackets, one on each side of the joists.
> Option 1 would be my preference.


option 1 was kind of what I was thinking of as well.

do you happen to know which joist hanger is the preferred one to use for my situation?

Thanks!


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## Yodaman (Mar 9, 2015)

measure the height of the joist and the width, looks like rough cut but can't tell from the pic. Then we can find what you need


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## andrewjs18 (Dec 14, 2011)

Yodaman said:


> measure the height of the joist and the width, looks like rough cut but can't tell from the pic. Then we can find what you need


I'll do that when I get home from work tonight and report back. thanks!


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## andrewjs18 (Dec 14, 2011)

the old tape measure is saying that the joist is 1 11/16th wide by 9 1/4 high. so a 2X10, eh?


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## Yodaman (Mar 9, 2015)

yes, try the std bracket first. Its going to be tight at the bottom but I think with some persuasion you will get it. If its just too tight then will need to get a bracket for 2" dimensional lumber. I have had to order them in the past with the assist of the counter help at my local lumber yard.


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## Homerepairguy (Aug 1, 2010)

andrewjs18 said:


> I'm not a contractor and my knowledge of proper terminology for different building makeups is definitely lacking, so please forgive me if I define something incorrectly.
> 
> in my basement, some of the joists that run the width of the house appear to be pulling away from the sill plate. there's only a few that are actually exposed to see - a previous owner of the house had concreted in most of the rim joists to seal them up, I suppose. the joists that I can see that concern me are a few that end right where my steps begin that go from my kitchen down into the basement.
> 
> ...


Your pictures don't show any support beams under the floor joists. That being the case, there appears to be a major problem caused by the floor joists pulling away from the joist headers (also known as rim or band joists). The only thing that appears to be supporting the floor joists are the fasteners (nails or lag screws) going through the header joist from the other side, into the ends of the floor joists. When the joint is tight, the shear force on the fasteners is concentrated at one point. When the joint is apart, the shear force is along the gap which is prone to bending the fasteners and weakening them.

IMO, the proper way to correct the problem is to use 1/4" thick angle iron on both sides of each floor joist. First, use lag screws to secure the angle iron to the floor joist so that the angle iron is even with the end of the joist. Then use bolts to secure the angle iron to the joist header. Then tighten the bolts to pull the header against the floor joists.

The angle iron will then serve to support the floor joist rather than just relying on the existing nails or lag screws to support the joist.

My solution from what I can see in your photos,
HRG


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## ront02769 (Nov 28, 2008)

i would just leave it alone....as nothing is going to happen for tine next hundredyears at least...unless you are planning on staying there that long. All of the stuff about shear force etc. is correct....but those joists STILL are not going anywhere. Don't believe it? Try to get one out! No,not really, but if you have ever done destruction, you would know that even things that look like they are falling apart are HARD to get apart! Ron


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## Yodaman (Mar 9, 2015)

Homerepairguy said:


> Your pictures don't show any support beams under the floor joists. HRG



Here in the NorEast, this technique for supporting floor joist is almost the norm for anything built prior to 1960. The joist are resting on a fastened ledger board by way of the cut notch. Gaps are deliberately left at the bottom of the notch to reduce binding and possibly causing the joist to split at the notch. As I stated above it is very common to see this separation. As the house matures, wood dries and shrinks. I don't believe the joists have actually pulled away by moving, and thus pulling them back with angle iron would be futile. The joist is simply shorter now than when the house was built. 
Personally I don't like the design and most failures that I have come across is a split right down the middle that started at the notch corner. The joist hanger bracket will transfer the loading to the bottom of the joist, Eliminating the downward pressure moment that wants to split it in half.


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## Homerepairguy (Aug 1, 2010)

Yodaman said:


> Here in the NorEast, this technique for supporting floor joist is almost the norm for anything built prior to 1960. The joist are resting on a fastened ledger board by way of the cut notch. Gaps are deliberately left at the bottom of the notch to reduce binding and possibly causing the joist to split at the notch. As I stated above it is very common to see this separation. As the house matures, wood dries and shrinks. I don't believe the joists have actually pulled away by moving, and thus pulling them back with angle iron would be futile. The joist is simply shorter now than when the house was built.
> Personally I don't like the design and most failures that I have come across is a split right down the middle that started at the notch corner. The joist hanger bracket will transfer the loading to the bottom of the joist, Eliminating the downward pressure moment that wants to split it in half.












I understand now. It looks like the ledger board is a 1x3 that's fastened to the rim joist. Then the floor joists are notched to sit on top of the ledger board. So no need for a support beam under the floor joists. ..... It does look like the floor joist is cracking right where a nail or lag screw is going into the floor joist which seems to indicate that the ledger board is not supporting the floor joist properly.

Since the joist in the picture looks like it has pulled away a little more than half the thickness of the ledger board, it seems prudent to pull it back so the joist has more area to sit on the ledger board. Because the separation might only get worse in time resulting in the joists falling off the ledger board.

Doesn't seem that joist hangers have enough strength to pull the rim joist tight to the floor joists. Plus because of the ledger board, the joist hangers would not be able to go under the floor joist and be fastened to the rim joist.

I personally would worry if the problem is not corrected so that the floor joist sits more on the ledger and there are angle iron brackets bolted to the rim joist to prevent further pulling apart.

Thanks for explaining how that ledger board works. The construction I saw while working two years as a carpenter either had floor joists sitting on 4x6 sills or used joist hangers attached to the rim joists.

Best regards,
HRG


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## Yodaman (Mar 9, 2015)

Yodaman said:


> As the house matures, wood dries and shrinks. I don't believe the joists have actually pulled away by moving, and thus pulling them back with angle iron would be futile. The joist is simply shorter now than when the house was built.



its doubtful you could pull in a floor joist without cutting all the individual nails coming down thru the sub and finish flooring. And if you did move it, would you create the same gap at the other end? 

The hanger bracket will not pull it in either, but will support it from the bottom of the joist even with the gap. Several post back we discussed how to attach it


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## carpdad (Oct 11, 2010)

That is a staircase header with a ledger that the joists are butting into. Joists are partly sitting on the ledger. Fill the space above the ledger and screw in the joist hangers. If using solid wood, predrill and counter sink. Don't drill into the header. Use wood screws long enough. At least 75% into the header, both filler and hanger.

The joists probably have at least 2 16d nails from the other side of the header. It looks like the nails are doing most of the work. That much gap (when next one is tighter) means the original cut was careless.


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## Homerepairguy (Aug 1, 2010)

Yodaman said:


> its doubtful you could pull in a floor joist without cutting all the individual nails coming down thru the sub and finish flooring. And if you did move it, would you create the same gap at the other end?


My suggestion was to move the rim joist toward the floor joist. Not move the floor joist to the rim joist. If angle iron was used with "bolts" through the rim joist, the rim joist could be pounded on with a small sledge hammer while the bolts are tightened.

But Carpdad has a good point. "That much gap (when next one is tighter) means the original cut was careless."



> The hanger bracket will not pull it in either, but will support it from the bottom of the joist even with the gap. Several post back we discussed how to attach it


I missed that but see it now. Yes adding fillers to match the ledger board would allow joist hangers to be used. 

Thanks,
HRG


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