Looking at this table you will see there is a choice in the size of floor joist 2 x 6 2 x 8 2 x 10 or 2 x 12 and there is a choice in the joist spacing 12 16 or 14.
Connecting 2 floor joists moves me off 16 inch centers.
Common joist spacings for 2 by 10 joists and other dimensional lumber sizes are 12 16 and 24 inches.
The rule of thumb is 6 foot span with a 2 6 on 16 centers.
0pt1m1z3 nov 23 15 at 16 47 usually when you are building headers or joists you want grade 2 lumber not the standard stuff that you can buy at home depot.
If adding additional framing be sure to keep all boards level and in plane across the tops.
I have 2 x 10 floor joists on 16 centers that span 16 between the foundation wall and a steel i beam.
See the image below for an example of joists spaced 16 on center 16 o c.
Common sense tells you that large floor joists can carry more load and spacing joists closer together also increases the load bearing capacity of a floor.
Joist span and spacing is set by your local building code.
If these problems remain unfixed sistering the damaged floor joists is only a band aid and the damage will only happen again.
But larger is not always better when builders are constructing a home or adding a room addition.
However when running spf 2 6 floor joists into the floor joist calculator referenced above you get a maximum span of 9 feet 8 inches with a minimum bearing length of 3 inches at each end on 12 centers.
For a more rigid feel 12 or less may be preferred.
The extra two inches of vertical distance when a floor is framed with 2 x 10 joists rather than 2 x 12s can be quite important for example.
When building a house or even a deck it is important to confirm you have the correct joist sizes spans and spacing before you get started.
Over notching or not jacking enough.
Trying to show you the importance of laying out your floor joists properly to make laying the floor easier and adding the proper amount of structure to carr.
The ends of the joists will sit on top of the same top plates that the 2x4s sit at both sides.
I want to add a fish tank and stand that will weigh 2000 lbs when full.
The floor joist spacing is the distance between the centers of any two installed joists.
Joists that are closer together can support more weight which allows the joists to span a longer distance than joists spaced further apart.
The tank will run parallel to the floor joists and will be located in the center of the span.
Deck joist spacing should never exceed 16 on center with the exception of max deck boards which allow for maximum 24 on center.
Generally newer home floor joists are made from 2x8s or new engineered i beams older homes however may have 2x6s instead.
