Purlin Braced to Joists

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gwitz

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I am contemplating the purchase of a home and need some advice on roof repairs. It is a small home measuring 24'x40' that was built in 1953. A new composite roof was installed in the past 6 months(old shingles were removed).

The roof sags in one area due to the purlin being braced to joists. I assume the resulting sway in the 2x6 rafters is there to stay. There is not a load bearing wall to properly brace to in this area.
Should I:
- Install a strongback to re-brace the purlin. If I go this route should I attempt to remove the sway?

- Just live with it as is, 60 years old whats done is done

- Some other idea from someone who has more experience than me
 
Well, as always, you should probably consult with an engineer for the correct answer.:D
However, with some pictures and some more answers, we can probably get you to a quick temporary fix, or even a pretty good guess as to what you can expect from an engineer.
So how about those pictures?.. because anything can be fixed with some $$...
 
Thanks for the reply. As of now the only picture I have is the portion of above the garage where there is no bracing(at least not yet). The build on the home portion in question is the same with the addition of purlin and braces running down to the joists.

Attic.JPG
 
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Most times it would require pulling one or two walls back in place, can be nasty. A photo from outside showing the sag would be good too.
 
Thanks. Here are a couple photos from photos from outside the home. Of course in the pictures I have you can get a real good look at the sag. I will try to get some better shots this afternoon.

hse1.jpg

hse2.jpg
 
Cut a hole through the ceiling and get a jack post on the sagging beam, slowly push it back it place. Sister another beam on there, secure the beam with more trusses.
 
Cut a hole through the ceiling and get a jack post on the sagging beam, slowly push it back it place. Sister another beam on there, secure the beam with more trusses.

I would absolutely not recommend jacking up any rafters till you know where the load points are. For every action, there is an equal and opposite reaction, don't forget.

As inspector stated, an engineer will be able to provide a road map of how to proceed. Money well spent in the long run. Just my :2cents:
 
I would have a pro look at it for peace of mind. Most people would live with it if its not changing. You should see clues if its changing. You could then stabilize it from moving more. If the plan becomes making it straight plan on some expense. DO NOT jack it up as a quick fix. Something like that take a lot of planning.


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Thanks for all the comments. Leaning towards bud16415 and nealtw advice. I can live with it how it is as long as I can keep it that way. I would much rather spend dollars and energy finishing out the garage and adding a larger porch. Just not one quite that big.
 
I was thinking just cover the garden area. We see alot of it up here, just to make houses look a little updated, not to much money. And hide the sag!
 
With a new roof just prior to your inspection you won’t find clues of movement up there. But you should be able to figure it out by inspecting closely inside and out. For the roof to sag something had to move. It could have been 50 years or more ago and stopped after some settling. You could maybe add some collar ties or something if when you walk around up there feel any bounce. Just tighten things up for peace of mind.

As a side note homes like this were built in mass quantities after the war and chances are the area of this house you will find others with quite similar bones. Walk around the neighborhood and see if others are a little swayback as well.
 
Nothing wrong with jimmying up structure. Roof beams sag all the time, if they sag 1" it is sure easy to push it back 1/2"
You can install these trusses and while your at it take you pry bar and push up the roof beam up a bit, looks like your roof us not sagging so much.
truss.gif
 
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Cut a hole through the ceiling and get a jack post on the sagging beam, slowly push it back it place. Sister another beam on there, secure the beam with more trusses.

So when the jack post just falls thru the floor or breaks a floor joist, do you just stand there with a dumb grin on your face.

The two samples of trusses you posted are designed for certain loads. How about you explain the difference and which one is used for what.

There is a key word that you always here with the word truss and that word is engineered.
 
Decided to take the easy route and ask the seller to correct it. Expected them to say no and use that as leverage for a reduction in price. They agreed, now hopefully it is done in adequately and passes inspection. Plenty of fun projects to do on the house that don't involve a hot Texas attic.
 
"So when the jack post just falls thru the floor or breaks a floor joist, do you just stand there with a dumb grin on your face."

You could put another jack in the basement bellow it. On second though i don't think it would need that much pressure. I think simple adding the some 2x4" trusses and using pry bar you could correct the sagging roof beam a bit, it looks like only 1". I'm assuming the rest of the structure is solid. Wood has memory it shouldn't be that hard to get it to remember.

"The two samples of trusses you posted are designed for certain loads. How about you explain the difference and which one is used for what."

If you add more structure but don't add more load what could go wrong? The trusses are ment to hold the roof up. Maybe the old roofing was too heavy?

I don't trust engineers so much,

tumblr_lij6rbD1dQ1qddyq5o2_500.jpg
 
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Jungle:You are making suggestions to people likely with less knowledge than yourself. The post in basement or crawspace should have been in your first write up. You might take chances with the floor but at least tell the guy there is a chance the floor should be braced.

We put up trusses all the time, and in any given set, the engineer might have three different styles. I am sure he has a reason, might be weight load or snow load or wind load. I don't know the difference they come packaged in order and we just put them where they belong.

With this house, we don't know what the problem is. If it is a couple rafters sagging then yes, you could straighten them out and add more lumber. But if the ridge board is sagging it could be that the front or back or both walls have leaned out allowing the center to come down. Not a problem with drywall. I have pulled a wall straight with come-a-longs. But if the house has plaster you would likely just add lumber so it would not move any more.
 
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