[donnaradicecubb]

Hello. My question is where to locate the two 4 x 4 support structures I am going to use beneath a garden window which is suspended off of the house. We estimate the weight of the garden window to be about 300 pounds.
I would like to position them at an angle from the bottom of the garden window to the house with lag bolts. The dimensions of the garden window are 72 inches wide by 30 inches high by 24 inches deep. The 24-inch dimension is the portion that extends from the house. SEE ATTACHED PICTURE FOR SIMILAR SITUATION. Thank you.

 

[chandler48]

The only problem with cantilever angle bracing is that it puts outward pressure on the top of whatever you put there, whether it is a balcony or a window. In your case, 24" is not a problem with bracing. Figure the size of the angle brace using the pythagorean theorem. Measure the height of the brace, multiply it by itself. Do the same with the 24" protrusion, add them together then take the square root of the answer. That is the length of the hypotenuse, or angle brace.

So if you want a 24" deep, by 24" tall brace.....24x24=576+576 =1152 Square root of 1152 is 34", so your brace would be 34" long-to-long

You could make corbels to form support along the length that would look good and beat angle bracing day in and day out.

 

[paul100]

Instead of supporting it from below, can you use a cable support system and support from above?

 

[donnaradicecubb]

Thank you very much for your response. Some additional context: This garden window was custom made and installed about 20 years ago. Since that time, there is evidence of "sagging" such that the side small casement windows are no longer true and cannot be closed adequately. Yes, we should have braced it when window was installed. So, to halt the potential additional sagging, I want to brace it. Your response indicated that the desire is for a 24-inch long hypotenuse, however I was looking at it from the perspective of doing a calculation that would tell ME what the length of the hypotenuse would have to be. My plan is to install a 2x4 which I will mount with lag bolts into the studs, and then "rest" the end of the brace on it to prevent further sagging. Does this additional information alter your response at all? Again, I am very appreciative of the time you took to respond to this inquiry!

 

[donnaradicecubb]

Not possible to support from above, but an excellent idea if it were possible. Thank you for responding.

 

[donnaradicecubb]

To further clarify, I am specifically looking for the optimal brace length, based on the dimensions and weight of the window. Your calculation says "34, but I am thinking that I did not pose the question correctly. Thank you again.

 

[wallylama]

The 34" dimension given is the long edge (hypotenuse) if you're 24" from the house and 24" below the window - see the attached calculator link that can be used for any dimensions you choose for your right triangle. With a 34" hypotenuse you'll have a 45 degree brace angle.

https://www.omnicalculator.com/math/hypotenuse

 

[donnaradicecubb]

Thank you! Is 34 inches and 45-degree angle the optimal placement of a brace to prevent further sagging of the window? Rather than ME specifying 34 inches/45 degrees, I was hoping there would be a calculation to tell me how many inches (and consequently, the angle that would result from these inches).

 

[donnaradicecubb]

Should not the weight (load) of the window be considered?

 

[paul100]

Are you going to jack up the window so the casements work? I would jack it up then build your supports in place. Do your measurements as you build it.

 

[donnaradicecubb]

Hi Paul. I already "modified" the casements to close askew since jacking the window up is not feasible at this point. Live and learn. Anyway, please take a look at the new attachment which better illustrates what I am trying to determine. Thank you.

 

[ratherbefishing]

OP, if you make the brace 24" up and 24" out, the Pythagorean theorem works. If you do a Corbel, like Chandler suggests, the Pythagorean theorem works, the outward load is eliminated and you can go smaller than 24x24. But if you want to change the angle from 90/45/45, you'll have to do some trig. Carpenters have the Pythagorean theorem down. Most don't do trig.

Actually, you don't need trig to figure the angles. since one is 90, the other two just add up to 90. But figuring the length takes some trig.