Thread: Joist spacing

This home was built in 2003. These joists are ten inch, spaced 24 oc. The floor was a little springy. Is this something you mention.

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Here's a nice span table (embedded in the guide) that answer all your questions, assuming you measured the span length.

Thank you for the info.

Originally Posted by mathew stouffer

This home was built in 2003. These joists are ten inch, spaced 24 oc. The floor was a little springy. Is this something you mention.

Yeah

The springy is something you should not feel. If a floor was not framed for the load and span, or forget that, just the deflection rate to keep tile from cracking then it will feel springy.

Springy bad. Solid feel good Just kidding but if you don't write something up and they feel it after, well, you know the rest of the story.

A floor framed to the minimum will allow a TV on a dresser to rock when you walk by.... at least when me and my 240lbs walk by. This one use to bug me but I've just come to accept it. I use the TV on the dresser only because I've noticed that situation several times before. Plates in a hutch or anything similar will respond the same.

It satisfied the min but was spring. Mentioned it in report cuz I do know the rest.

There was a while here back early 90's maybe, can't remember for sure, when TJI's were just sort of taking off that developers were framing 24"OC. The idea of course was to save money. Complaints about springy floors pretty much ended the practice.
In this type of application you can look for ...
- if the 9-7/8 TJI is listed for 24"OC for full interior occupancy load; However this tends to be a bit of a waste of time since it was probably engineered by an architect and approved by the Muni.
- The really easy way to nail this install is to look for glue from plywood to joist. I have yet to see a 24"OC install Spec that DIDN'T require the ply to be glued as well as nailed or screwed. If you don't see glue oozes at least along some areas chances are its not glued at all. No contractor is good enough to apply glue and not have some ooze over the sides of the joist. No glue, major defect.

Would you rather have a springy floor that gives a little or one that is so stiff that it has no flexibility and will crack under load?

Believe it or not.. I actually had a structural engineer tell me that springy is good! What do you feel when you walk in the mall? You can actually feel the floor moving up and down. What about skyscrapers? they aren't built to be stiff.. they want them to be able to move.

However.. try telling that to the homeowner and like others say... trouble!

The springy may also have something to do with the newly found information that some wood has been overrated by the grader.

In other words... the lumber is not able to span as far as they originally thought! This may be the case!

Is it possible that the spring is from the sub-floor thickness and not the joist?

Mention spring in floor, why not, buyer may not have noticed it.

3/4 T&G Oak flooring will remove alot of the spring that is there. Solved spring in floor in past by using flooring rather than adding joist to stiffen.

Originally Posted by target inspect

Depends on the length of span silly! VS: the load above configured! Duuuh Idiot!

Not sure who this comment was directed at, but a little uncalled for.