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New porch, bowed walls

deweybalfa's picture

Hi- this is my first time posting in a forum.  

I recently built a porch 22' wide by 16' long, gable roof 8:12 pitch.  My goal was to limit the number of ties to leave it somewhat open.  I built two trusses and carriage bolted them together using 2 1/2" carriage bolts.  My concern is I didn't put the chord of the truss low enough and I've noticed something that make me think I need reinforcement.  This is a no snow area and the roof is pine tongue-n-groove and shingles.  

The wall in the center of the porch seems to be bowing out (I've noticed the post is 1" out of plumb pushing outward).  It's only about 2 weeks old since we put the roof on and I'm considering getting two come-alongs and strapping the sagging posts together and wratcheting them back in and installing a 3/8" or even 1/2" steel cable to keep them from bowing back out.  Is this something that is relatively simple to do?  like getting two come-alongs and sucking the posts back to plumb them out?  I've read quite a few things on this topic, but I wanted to add a picture and get your advice.  

Maybe I'm over thinking this and it isn't a big problem, but I'm new to building and want to make sure it won't worsen as time goes on.

It sounds like inadequate (post #215618, reply #1 of 8)

It sounds like inadequate ties holding the walls together.  Apparently you used "collar ties" rather than regular bottom ties, and that approach rarely works well unless carefully engineered.


Of all the preposterous assumptions of humanity over humanity, nothing exceeds most of the criticisms made on the habits of the poor by the well-housed, well-warmed, and well-fed.  --Herman Melville

Pictures would help. I'm not (post #215618, reply #2 of 8)

Pictures would help. I'm not sure I understand the wall in the center bowing. If the trusses are causing the walls to bow it would be the walls the outside of the trusses bear on that would move.  2 weeks seems really fast for the walls to bow as well. If you sight along the top of the walls are they they bowed out in the middle?

Florida Licensed Building Contractor, 50 years experience in commercial remodeling, new homes, home remodeling and repairs and all types building maintenance.

Walls pushing out? (post #215618, reply #3 of 8)

Yes- the walls are slightly bowed in the middle-- my idea at this point was to try to pull them back in with a come-along perhaps, and then reinforce either with adequate ties or cables to prevent them from pushing any farther out-- as I sight down the wall, the middle of the wall is the part that has pushed out about 1" out of plumb over 9' of post, outwards- I'm attaching a picture of the porch that shows the trusses which are evidentally not low enough to the top plates

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The bottom chord of the (post #215618, reply #4 of 8)

The bottom chord of the trusses is a bit high. The time frame still surprises me. Where the outside walls straight when you built the trusses? Did you have a string line on them to make sure. You're there, I'm not but my guess would be that they bowed under construction and you've just noticed. I think I'd run string lines down both walls, measure the deflection and wait a month or two to see if it gets worse. If it does then your idea of cables will work but they will have to be permanent. If the deflection doesn't get worse I'd leave it alone.

Florida Licensed Building Contractor, 50 years experience in commercial remodeling, new homes, home remodeling and repairs and all types building maintenance.

thanks for the help and (post #215618, reply #5 of 8)

thanks for the help and advice :)

I'm going to keep an eye on it and if it gets worse, I'll try to jack the ridge up slightly in the middle and attempt to pull the posts together!

Keep in mind that, unless (post #215618, reply #6 of 8)

Keep in mind that, unless extra care is taken, about a half inch in 9 feet would be likely just due to the natural warp of the wood, etc.


Of all the preposterous assumptions of humanity over humanity, nothing exceeds most of the criticisms made on the habits of the poor by the well-housed, well-warmed, and well-fed.  --Herman Melville

Nope, not even close to true. (post #215618, reply #7 of 8)

Nope, not even close to true.

Florida Licensed Building Contractor, 50 years experience in commercial remodeling, new homes, home remodeling and repairs and all types building maintenance.

jack it (post #215618, reply #8 of 8)

That's what I was going to recommend, if you have a bottle jack, jack it up and snug it up at the same time. Could use a few cables, or a few threaded rods with a center-span turnbuckles.


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