Free standing bench leg design

[Ban Bot]

We had 3 long free standing benches on our front patio that were 8', 10' and 12' depending on the house wall they were against.

They had no arms or back supports.

My wife really liked them but the legs were rotten because whoever built them used standard 2x4s. The bench boards (2 x 8) are pressure treated. I have sanded these to re-use them.

But I need a leg design.

The previous design stunk. It was all 2x4s. For the short bench on one side it had two "support braces" 2x4s run in parallel perpendicular to the 2x8 bench boards. These 2x4s were spaced to allow a vertical 2x4 "legs" to sit in between. On the back side against the house wall the "support braces" only came to the edge of the 2x8 bench board so the leg wedged into between the "support braces" and the bench board. This part would all go flush against the wall.

On the front side the "support braces" extended past the 2x8 bench board and the "leg" on the front, instead of meeting up on the bottom of the bench board, were forward enough to clear the bench. The front legs were 6" above the bench board and were nailed into the "support braces".

So of course the legs were wobbly.

The best idea I can come up with:

Go with the same 2x4 "support brace" idea. But instead of 2x4 legs I would go for 2x6 legs and "notch" them like an 'L' with the numb the height of the thickness of the bench boards. The bench board would sit in the low spot of the 'L'.

For the legs I would run a 2x4 from leg-to-leg to provide additional stability.

I would use pressure treated wood. Looking for some Copper Naphthenate but didn't see it at Home Depot.

For the 10' and 12' benches there would be a middle support leg.

I know there has to be a better design than this. Any suggestions/links would be helpful

 

[Greenman]

Use 2 2x4's to form an X. Mount the X on the bottom of the bench with another 2X4 from the bottom of the bench to the center of the X at a 45 degree angle for lateral support.

 

[Scarpozzi]

If the patio is concrete, you should consider investing in rubber feet for the bottom of the legs. Anything to keep the wood from touching masonary will extend its life and keep it from wicking water.

Creating triangles is the key to making the structure strong. Look in the decking section of HD or Lowes or in the hardware section for metal to reinforce the joints. It doesn't have to be particularly thick to do the job. If you use screws to fasten the joints, the swelling/expanding/contracting of the wood is what causes them to break down over time. Using metal plates helps keep the joints tight.

 

[Howard]

Sketch please.

 

[bigi]

Just build a bench myself. I cut 2 composite decking boards into 12x5 pieces and screwed both underneath my bench "legs" perpendicular to length of bench. Works great - provides isolation from bottom (moisture) and makes my bench very stable.

My bench legs are 2 pieces from tree trunks so all works very well visually.