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Porch to 4-Season Conversion in NJ: Framing questions

F

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Jan 5, 2018
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8
Location
NJ
Hello,

I am planning on converting a screened in, single story porch to a 4-season sunroom.

Below is a very primitive drawing I made, but it shows you my basic plan. My porch is constructed from mainly 4x4's spaced every 47.5" on center providing 44" of open space between each of them. There is a 2x4 bottom plate and a double 2x4 top plate. The porch has a shallow pitch, rolled roof that has the potential to hold a lot of snow. The porch was added to the house well before I became the owner.

I'd like to add jack studs to the inside of each 4x4 and install a 2x6 header above each opening. I plan to make a 28" kneewall. This will give me roughly 41x52" for windows. The photo below is double-hung version, which is what I'm steering toward. If I decide to go with sliders, I may have to take some 4x4's out and frame appropriately.

My questions are:

1. Are headers for structural integrity appropriate and required in this situation? A 2x6 header will bring the tops of my windows to door height.

2. Are there restrictions to the minimum height of the kneewall? Someone told me that if I go too low, code may require tempered glass.

Thank you in advance.

XRfeixbpUMkCf5-aqvi2cY6U_kqWfC1yG1jIYyAdq6yzplkWdvVGyS8Tuh3dmUpyJA8U_NMeZWIQLCkU2I1VUw=w1366-h662-rw
 
No worky for me.............

BTW......Welcome!

I would suggest drawing up what you are proposing, and take it to the AHJ. They can't design it for you...........but they can tell you.........no, that will not work.
 
Ugh. Weird. I'm trying to link off my Google Photo's. It says the link is public. It works for me and I'm not even logged into Google.
 
There shouldn't really be a need for any headers over the window. What you have right now is supporting the load of the roof, and there is no increase to the dead load.

You might still want to see what the beam is that is holding up the roof to make sure it is adequate before putting some fragile windows under it though.
 
Agree with TM.....If the roof is already there, enclosing it drives on header upgrades....Wall bracing will be another matter...The tempered glass thing you can get around by keeping the panes to less than 9sqft if I am not mistaken, but I can't imagine tempered is a big expense...
 
R308.4.2 Glazing adjacent to doors.
Glazing in an individual fixed or operable panel adjacent to a door shall be considered to be a hazardous location where the bottom exposed edge of the glazing is less than 60 inches (1524 mm) above the floor or walking surface and it meets either of the following conditions:
1. Where the glazing is within 24 inches (610 mm) of either side of the door in the plane of the door in a closed position.
2. Where the glazing is on a wall perpendicular to the plane of the door in a closed position and within 24 inches (610 mm) of the hinge side of an in-swinging door.

R308.4.3 Glazing in windows.
Glazing in an individual fixed or operable panel that meets all of the following conditions shall be considered to be a hazardous location:
1. The exposed area of an individual pane is larger than 9 square feet (0.836 m2),
2. The bottom edge of the glazing is less than 18 inches (457 mm) above the floor,
3. The top edge of the glazing is more than 36 inches (914 mm) above the floor; and
4. One or more walking surfaces are within 36 inches (914 mm), measured horizontally and in a straight line, of the glazing.
Exceptions:
1. Decorative glazing.
2. Where a horizontal rail is installed on the accessible side(s) of the glazing 34 to 38 inches (864 to 965 mm) above the walking surface. The rail shall be capable of withstanding a horizontal load of 50 pounds per linear foot (730 N/m) without contacting the glass and have a cross-sectional height of not less than 11/2 inches (38 mm).
3. Outboard panes in insulating glass units and other multiple glazed panels where the bottom edge of the glass is 25 feet (7620 mm) or more above grade, a roof, walking surfaces or other horizontal [within 45 degrees (0.79 rad) of horizontal] surface adjacent to the glass exterior.
 
Generally screen porch would have uplift connections, once enclosed the braced walls provision should be addressed as applicable "Raised floor system post or pier foundations supporting braced wall panels shall be designed in accordance with accepted engineering practice."

Tip.JPG


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Ok, cool. Here's more:

https://ibb.co/koU0Rm
https://ibb.co/hapdCR

I plan on using double hung windows, so I shouldn't have an issue staying below 9 sq ft per pane and I don't plan on having them less than 18" from the floor.

Good to know about the headers. I didn't think I'd need headers above each window for structural integrity since I'm not removing anything that is already. I will, however, need to use headers for something to mount the windows to. Maybe I'll use 2x4's instead of 2x6's. I will be removing one of the 4x4's on the left hand wall to install a slider door there. That may warrant a header. I realize screened in porches using 4x4's don't use standard framing practices.
 
UM...
I don't like the looks of that: https://ibb.co/koU0Rm
Stick with your original plan with new headers. Lumber on its flat is not nearly as strong as on its edge. I would imagine that what you have there flexes quite a bit depending on your snow/ice loads. adding the headers will help transfer the roof loads around the windows and will reduce any flexing in the beam holding up the roof.
 
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