Hello
I've searched a lot in this forum to get some clarity.
I need some help with calculating how I could change the height of my floor joists.
My hope is by adding 5 cm to the battens (which the joists rest on) and reducing the height of the floor joists by 5 cm to gain 10 cm in ceiling height in my basement.
House from 1930.
Current joists 65x210 (Desired height at most around 150)
Span 4 meters
I've read a bit about screw-gluing two pieces of 45x145 construction but I'm unsure if that's enough.
Anyone knows how to calculate this? There’s a lot of info, but nothing that really shows examples of how to do it if you don't want/can't use standard floor joists.
Thanks in advance
I've searched a lot in this forum to get some clarity.
I need some help with calculating how I could change the height of my floor joists.
My hope is by adding 5 cm to the battens (which the joists rest on) and reducing the height of the floor joists by 5 cm to gain 10 cm in ceiling height in my basement.
House from 1930.
Current joists 65x210 (Desired height at most around 150)
Span 4 meters
I've read a bit about screw-gluing two pieces of 45x145 construction but I'm unsure if that's enough.
Anyone knows how to calculate this? There’s a lot of info, but nothing that really shows examples of how to do it if you don't want/can't use standard floor joists.
Thanks in advance
Hello fatman!
Now I feel like a real killjoy, but I have to say that the project is a risky venture.
Replacing the current 65x210 with 2x(45x145) is not enough. It is much weaker.
If you want to reduce the dimension that much, I think you need to look into other materials like steel beams, etc.
And I still think you would have to reinforce with posts.
I live in an old house myself and have only dared to reinforce, never reduce what's existing.
Is there no possibility to go downward? (Dig out the floor?)
I feel like the worst killjoy!
I hope someone says I'm wrong and has a better solution!
Johan
Now I feel like a real killjoy, but I have to say that the project is a risky venture.
Replacing the current 65x210 with 2x(45x145) is not enough. It is much weaker.
If you want to reduce the dimension that much, I think you need to look into other materials like steel beams, etc.
And I still think you would have to reinforce with posts.
I live in an old house myself and have only dared to reinforce, never reduce what's existing.
Is there no possibility to go downward? (Dig out the floor?)
I feel like the worst killjoy!
I hope someone says I'm wrong and has a better solution!
Johan
Had the same problem and got a lot of help from http://www.skogsindustrierna.org/LitiumDokument20/GetDocument.asp?archive=3&directory=749&document=9001
If you can fit in a load-bearing beam, 120x45 cc30 is no problem.
If you can fit in a load-bearing beam, 120x45 cc30 is no problem.
Here you can see a table for floor joists. I also think it's completely unthinkable to go down to 45x145 even if you were to use double glued screws.
As I said, see if you can go downward instead! If you haven't done anything in the basement yet, you have an uninsulated floor and then it might still be an idea to chisel up and insulate.
As I said, see if you can go downward instead! If you haven't done anything in the basement yet, you have an uninsulated floor and then it might still be an idea to chisel up and insulate.
Thank you for all the responses.
Going downward has also been an option (which we will also do). This spring, we drained and went a bit below the current outer walls. The problem was that unfortunately, we couldn't go down as much as I had hoped.
As a result, the idea was sparked to reduce the joists after we had determined that "only" the floor was on them.
We have also considered installing a steel beam to thereby only get a 2-meter span on the wooden beams.
I thank everyone for your input and suggestions!
Going downward has also been an option (which we will also do). This spring, we drained and went a bit below the current outer walls. The problem was that unfortunately, we couldn't go down as much as I had hoped.
As a result, the idea was sparked to reduce the joists after we had determined that "only" the floor was on them.
We have also considered installing a steel beam to thereby only get a 2-meter span on the wooden beams.
I thank everyone for your input and suggestions!
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Good luck!
Johan
Johan