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I am having the ceiling in the finished part of my basement redone, and have it fully open now. I can see the connection of the joists to the headers have given somewhat, as the house is 85 years old and the joists are not in hangers. The separation laterally varies from 1/8" to 3/8" from joist to joist and vertically some are fine while others are displaced 1/8" to 1/4". There is no visible deflection along the length of the joists, and from the floor above there is one minor but noticeable (when standing on it) low spot in the floor.

Picture attached, should I be concerned or is this normal in a house of this age and not likely to worsen? Would it be advisable to retrofit hangers?

enter image description here

Paul D
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  • It would be very helpful to see a photo of both outside sills where the rim joist meet the top of the basement wall. Of particular interest would be the space from the face for the wall to the rim joist, both from the inside and the outside. Joists do not shrink much in long dimension, but rather across the grain. Of interest would be signs of wall movement in the floors above (indicated by long vertical cracking). An examination of the attic joists and rafters for the gapping condition and any signs of stress would be helpful in getting an overall assessment. – HerrBag Mar 16 '13 at 16:16

2 Answers2

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Good question Paul, The situation with your framing is not really normal, but not uncommon for a house that age. Any time there is separation of framing members, it is a reason for concern and should be addressed. However, I would not say it is a major or alarming problem. There could be a couple of different reasons for this separation. The joists may have shrunk over the years from not being well dried at the time of construction. The other reason could be settling of the outside supporting structure or foundation. A good first step is to confirm level of the joists using a long level or a laser. I prefer using a laser as you can check level and deflection at the same time. This may also help you determine the cause of the floor sag. Any irregularities can be corrected by slight jacking, sistering, shimming or adding supports.

Assuming your framing is fairly level or corrections are made, I would recommend adding joist hangers to all the members. It would be impossible to close the existing gaps, and the gripping force of the existing nails has been compromised over the years from wood shrinkage. Simply hammering them in tighter would not be a permanent solution. When selecting the hangers, be sure to get the ones that have holes that allow securing to both the joists and center beam. Use the appropriate size joist nails or screws for the holes in the hangers, don't under size and never use drywall screws. If you use joist nails, get or rent a pneumatic palm nailer, it will make the process a whole lot easier.

Once you have properly installed hangers, you can go ahead with your finishing project being confident there will be no further separation of the joists from the beam.

shirlock homes
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  • I want to elaborate a bit more on some observations. Looking at the gaps, they look fairly consistant. If the gaps are consistantly wider on the bottom of the joist than the top, the center beam may have settled, if wider at top then the outer wall may have settled. If even, shrinkage may be the culprit. Without seeing the supporting foundation walls where the joists and beam rest and shoot a laser, I cannot comment if the problem will worsen. What you need to address is the vertical support of the joists. Since they are fixed mechanically by the floor boards and hopefully secured to the sill – shirlock homes Mar 15 '13 at 09:24
  • The joists should not have the ability to move laterally unrestricted. At this time, attempting to draw the joists closer to the center beam may have undesired results. Lateral movement will effect flooring, trim etc above. If you have not seen separation of any of the above elements, do not attempt to change the lateral dimensions, rather concentrate on the load bearing support via beam hangers to augment the exposed nails. – shirlock homes Mar 15 '13 at 09:32
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I agree with everything Shirlock said regarding adding joist hangers, but first I would advise you to stabilize your joists from whatever is causing separation. Edit The gaps you are seeing are not caused by shrinkage. The gaps were either there when constructed or have developed over time. On a positive note, the joists you've shown don't appear to be sagging.

A fairly new product that is code required (IRC R502.2.2.3 for decks is the lateral load connector device (LLCD). This device will, at a minimum, stabilize the joists from further separation. New decks require 2 of these devices per deck. I would suggest every fourth joist to start. They must be carefully torqued to specification. Careful retightening of the connectors may be able to reverse your pull away condition. Care must be taken to make adjustments slowly and to monitor the other end of the joists for new pull aways. If that is the case, hanger bolts (special screws with 1/2 wood threads and 1/2 machine threads) with connector nuts could pull in the rim joists at the same time (using only 1 lateral connector and the hanger bolt).

enter image description here

I am not saying all the gap can or even should be taken out, but as Shirlock has noted, the joists are not presently up to code.

Careful placement of the hole for the LLCD will allow use of joist hangers at the same time as the LLCD. It may be that the connector bolt may have to be removed during joist hanger installation, and then replaced afterwards.

HerrBag
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  • The LLCDs certainly would not hurt in this situation, but since the joists should be connected at the sill, there is not the unrestricted lateral movement potential as one would have with a deck. These ties will not add any load support to the joists. This of course depends on if there is any movement of the sill end of the joists, which is unlikely but yet to be determined. These ties are perfect for new construction, but not really designed to close gaps in old construction with large existing loads mechanically fastened, such as the floors and partition walls. – shirlock homes Mar 15 '13 at 09:44
  • These ties would be beneficial in stabilizing a situation where the movement was ongoing, assuming the root cause was corrected first. I am not dissing the idea, just questioning the value of using them on an 85 yr old house that may have settled a bit many years ago and since stabilized, which is a very common condition. As mentioned earlier, an inspection of the foundation and simple level survey really needs to be done before any extreme measures should be considered.Chances are that there are no serious problems and just a victim of age and poor construction practices of the time. – shirlock homes Mar 15 '13 at 09:58