I have a 20′ section on the back of my house that has a 1.5′-12′ slope which I read is considered a flat roof. I have puddling problems and mold from statnding water. The prior owner joisted over 12′ of 4-12 slope roof and 12′ of really flat roof with spliced 2x6x12′ and 2x6x8′ joists 16″ o.c. Is it concievable to jack up this entire section to 4-12? I realize the peak of the roof will have to move and I’ll have to extend the new joists and the old ones too with splices. Do you think it is doable. I have put additions on houses and am no stranger to rough carpentry.
The reason I got the idea is that I peaked in between roofs and and saw a knee wall supporting the joist splice which rests on the old flat roof which is sagging a bit in my dining room.
Replies
Ed
"The reason I got the idea is that I peaked in between roofs and and saw a knee wall supporting the joist splice which rests on the old flat roof which is sagging a bit in my dining room."
sure, designed correctly. But don't splice. You saw what happened the last time.
Mark
Too much load and not enough brains.............
Thankfully no one was hurt bad.
Bldg Inspector to investigate if there was too much weight on the roof..............
ya think>
Yeah, I think there was a bit too much weight, and I'm sure it being unequally distributed was a problem, no doubt. I would really like to find out the whole story on this one! I'm suspecting a problem like rot or something else was a contributing factor. The roofing company has been in the business a long time and is rated as high as possible with the BBB, but the way they did this job makes me wonder WHAT WERE THEY THINKING!
Spliced rafters over a sagging flat roof?
Sounds like a terrible idea to me.
To get back to the original topic, I can't tell for sure from the description, but it sounds like it's already effed up. Don't eff it up more -- don't splice the main rafters (I assume you mean "rafters" and not "joists") unless the splice can rest on a wall. (The same goes for horizontal joists.)
Also, it's unclear what span you're talking about. Common rafters are limited to something like 18 feet in length, depending on snow load, etc.
I was indirectly involved in something similar. Shingles stocked along the ridge of a roof. Rafters couldn't handle the load and collapsed.
We built new trusses for the house once they sorted out who had to pay for what.
They are talking emergency demolition on this house, because it may collapse into the house next door. The wall is blown out and temporarily propped up, I have to think it's seriously damaged. But maybe it's not as bad as it looks. I'll keep an eye on it, but the news never follows up on those stories.