nealtw
Contractor retired
Whow, slow down you didn't read half of what was talked about up above.
If you want to go off half cocked with little or no idea of all the dangers, and without consulting an engineer, I too am out.
Sagging Roof on Shop
- Thread starter Cooter85
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Help Support House Repair Talk:
Whow, slow down you didn't read half of what was talked about up above.
If you want to go off half cocked with little or no idea of all the dangers, and without consulting an engineer, I too am out.
Dont get me wrong, I am very concious of the fact that I can do even more damage, or worse, collapse a roof on top of myself. Thats why I am doing my research, and throwing it out to you fine folks for advice, and I greatly appreciate all the help so far. The plan is still being developed, and I don't intend on going further than what feels safe.
I simply can't afford to pay 10's of thousands of dollars to rebuild it, so I'm gonna work with what I've got. I know the best way would be to get a professional to redesign and rebuild, but I'm thinking more like whats gonna give me at least 20 or 30 more years.
I might come off like I lack a healthy dose of fear, but I am just 'cautiously optimistic.' Then again, you only live once, right?
I simply can't afford to pay 10's of thousands of dollars to rebuild it, so I'm gonna work with what I've got. I know the best way would be to get a professional to redesign and rebuild, but I'm thinking more like whats gonna give me at least 20 or 30 more years.
I might come off like I lack a healthy dose of fear, but I am just 'cautiously optimistic.' Then again, you only live once, right?
nealtw
Contractor retired
Some times you can try something and if it doesn't work go to plan B.
This not one of those places. When you consider all the things that could go wrong, time is on your side.
You know the saying, For every action there is an equal and opposite reaction. You have to be really sure you understand what every action gives you and how to make it work for you.
Your statement above, let's look at that. I just have a few question.
How much pressure is pushing the structure out side ways.
How much weight can 1/4 cable pull, with some particular clamping method that you were thinking about.
Drill a hole in trusses and pull.
How much weight could you pull before the rafter splits, releasing all that pressure at one time.
Will the floor structure be structurally sound enough to pull that kind of weight.
IF we agreed this would be a good plan, these are the questions you ask an engineer. No body here can come up with the answers.
The cheapest way would be to stabilize it just where it is.
So what kind of budget would you think would be max.
This not one of those places. When you consider all the things that could go wrong, time is on your side.
You know the saying, For every action there is an equal and opposite reaction. You have to be really sure you understand what every action gives you and how to make it work for you.
Your statement above, let's look at that. I just have a few question.
How much pressure is pushing the structure out side ways.
How much weight can 1/4 cable pull, with some particular clamping method that you were thinking about.
Drill a hole in trusses and pull.
How much weight could you pull before the rafter splits, releasing all that pressure at one time.
Will the floor structure be structurally sound enough to pull that kind of weight.
IF we agreed this would be a good plan, these are the questions you ask an engineer. No body here can come up with the answers.
The cheapest way would be to stabilize it just where it is.
So what kind of budget would you think would be max.
I understand engineering fairly well but I am not a structural engineer. There is a lot to be said for bringing in an expert in whatever specific field your problem involves. It is always money well spent.
I also look around where I live and see all these wonderful century old homes that are rock solid still and barns built from 12x12 hand hewn hard wood timbers 150 years old and some still built today by the Amish here. I marvel at the engineering that was done by the seat of their pants. It was only 50 years ago when I grew up and even then a far different time when things were still seat of your pants engineered to a large degree. It is true though the bad designs and plans aren’t around as a testament as they fell down a long time ago. So what I see is the best or the best.
Back on topic:
Inspector D laid out two workable solutions. A central beam and support columns or a central wall down thru the building and into adequate footer or footings. The beam would give you free span like you have now with the exception of one or two columns inside the building. The wall would divide both floors in half except for doorways that could be added to it.
The discussion Neal and I were having with you is a third option and that is trusses built in place better than what you have now that are failing. The two rafters and a collar tie are a very basic truss system and easy to calculate the strength of. The collar ties are in tension and most likely more than strong enough in tension given good attachment points at the end. They didn’t stretch 1.5” so the nails had to move. If the builder had put one on each pair of rafter we most likely wouldn’t be talking. If they had been attached better we wouldn’t be talking. The only other mode of failure that would allow movement would be if the rafters were bending between the collar and the birds mouth. That is easy to check with a straight edge and you didn’t mention a bow, but you should check for that. When I was a kid builders used to spike these together with huge nails that were extra long and then clinch them by bending over the end. I remember my dad showing me how to clinch a nail as a kid and him explaining how that will never pull out. No one does that today that I know of.
As to what method you use I think you have a good idea now of your options and if you hire an engineer you will know the questions to ask him and his plan of action would outline all the details of the how to. If you go seat of your pants we can offer ideas etc . just realize nothing we say is cut in stone.
I like the commercial ties that I feel could be used to close the top and hold it closed in the future when used as a hurricane tie. How many and what size would be the question. They looked like they are 7 bucks each. I doubt I could make anything in my shop for less even with free labor. As to the cables / chain and how to attach. Holes and shackles plating the sides of the rafter where the bolts or holes would be located or even how hard the pull would be, are unknown. Would you pull both sides at once or pull one at a time as Neal suggested pulling from the floor and the strength of that attachment point are questions to be answered? Cables are quite strong but do stretch. I would want cable stretch to be minimum and would upsize to keep it at that. Chain is a better way to go as it has a really low stretch factor.
You could start off by counting the rafters and the length and figuring the weight add in the weight of the sheathing and shingles and come up with a weight of the roof on one side. Knowing the angle of the roof you can figure the reaction force needed to hold the roof at its base if you had no collar ties. Simple statics problem. Then knowing how far up the collar ties are you can calculate the tension required for one collar tie to hold that force again basic statics problem. Then take that force and divide it by the number of ties you have. To get an idea how many you might need. The force you came up with at the bottom isn’t what you need to pull in with it is the force to just hold it. Then it gets tricky. How much additional force will it take to straighten those bent nails back and react against all the twisting and set that the wood has taken over the years. I don’t know how to figure that and it will be interesting to see how an engineer figures it. If it is 2x or 5x or 10x the holding force maybe they know from experience.
Stabilizing it would most likely be fine as a fix except you would be left with gaps and a bent outside wall. Would that be a problem down the road if you go to sell it. You would need something to show it was now sound and an engineer’s report saying it was good and proof of the fix would go a long way.
All things to think about.
I also look around where I live and see all these wonderful century old homes that are rock solid still and barns built from 12x12 hand hewn hard wood timbers 150 years old and some still built today by the Amish here. I marvel at the engineering that was done by the seat of their pants. It was only 50 years ago when I grew up and even then a far different time when things were still seat of your pants engineered to a large degree. It is true though the bad designs and plans aren’t around as a testament as they fell down a long time ago. So what I see is the best or the best.
Back on topic:
Inspector D laid out two workable solutions. A central beam and support columns or a central wall down thru the building and into adequate footer or footings. The beam would give you free span like you have now with the exception of one or two columns inside the building. The wall would divide both floors in half except for doorways that could be added to it.
The discussion Neal and I were having with you is a third option and that is trusses built in place better than what you have now that are failing. The two rafters and a collar tie are a very basic truss system and easy to calculate the strength of. The collar ties are in tension and most likely more than strong enough in tension given good attachment points at the end. They didn’t stretch 1.5” so the nails had to move. If the builder had put one on each pair of rafter we most likely wouldn’t be talking. If they had been attached better we wouldn’t be talking. The only other mode of failure that would allow movement would be if the rafters were bending between the collar and the birds mouth. That is easy to check with a straight edge and you didn’t mention a bow, but you should check for that. When I was a kid builders used to spike these together with huge nails that were extra long and then clinch them by bending over the end. I remember my dad showing me how to clinch a nail as a kid and him explaining how that will never pull out. No one does that today that I know of.
As to what method you use I think you have a good idea now of your options and if you hire an engineer you will know the questions to ask him and his plan of action would outline all the details of the how to. If you go seat of your pants we can offer ideas etc . just realize nothing we say is cut in stone.
I like the commercial ties that I feel could be used to close the top and hold it closed in the future when used as a hurricane tie. How many and what size would be the question. They looked like they are 7 bucks each. I doubt I could make anything in my shop for less even with free labor. As to the cables / chain and how to attach. Holes and shackles plating the sides of the rafter where the bolts or holes would be located or even how hard the pull would be, are unknown. Would you pull both sides at once or pull one at a time as Neal suggested pulling from the floor and the strength of that attachment point are questions to be answered? Cables are quite strong but do stretch. I would want cable stretch to be minimum and would upsize to keep it at that. Chain is a better way to go as it has a really low stretch factor.
You could start off by counting the rafters and the length and figuring the weight add in the weight of the sheathing and shingles and come up with a weight of the roof on one side. Knowing the angle of the roof you can figure the reaction force needed to hold the roof at its base if you had no collar ties. Simple statics problem. Then knowing how far up the collar ties are you can calculate the tension required for one collar tie to hold that force again basic statics problem. Then take that force and divide it by the number of ties you have. To get an idea how many you might need. The force you came up with at the bottom isn’t what you need to pull in with it is the force to just hold it. Then it gets tricky. How much additional force will it take to straighten those bent nails back and react against all the twisting and set that the wood has taken over the years. I don’t know how to figure that and it will be interesting to see how an engineer figures it. If it is 2x or 5x or 10x the holding force maybe they know from experience.
Stabilizing it would most likely be fine as a fix except you would be left with gaps and a bent outside wall. Would that be a problem down the road if you go to sell it. You would need something to show it was now sound and an engineer’s report saying it was good and proof of the fix would go a long way.
All things to think about.
nealtw
Contractor retired
Balloon framed structures were built like this and worked.
I would suggest building this inside from the bottom up.
By cutting a hole in the floor just big enough to work a stud up from below and build a new wall inside both sides and connect that to the original studs.
Then with the help of an engineer, things might be pulled into place or locked into place as is.
I would suggest building this inside from the bottom up.
By cutting a hole in the floor just big enough to work a stud up from below and build a new wall inside both sides and connect that to the original studs.
Then with the help of an engineer, things might be pulled into place or locked into place as is.
Ok, I called a contractor to come take a look, I will see what he says. I was just going to go for it, but if more experienced guys are telling me I need help, I will get a professional opinion.
This is my first home, only been there a little over a year, so I want to do everything myself if I can. Also, just had our first kid 2 months ago, so money is tight. If I can save a few thousand by doing myself, I would rather take that option. Appreciate the word of caution.
This is my first home, only been there a little over a year, so I want to do everything myself if I can. Also, just had our first kid 2 months ago, so money is tight. If I can save a few thousand by doing myself, I would rather take that option. Appreciate the word of caution.
nealtw
Contractor retired
Congrats on the baby and the first home.
There is no one here that would like to see you hurt or with out a garage but we are more than willing to help.
Just sometimes understanding is more important than a getterdone attitude.
See what your contractor has to say , throw some ideas that you have got from here and see what he says.
Be sure to let us know what he is saying.
Watch out for the guy that doesn't think the engineer is needed.
Contractors don't like coming out so you can pick his brain and there will be no job for him. Offer to pay him an hour or two.
slownsteady
Well-Known Member
I don't know what an engineer would cost in your area, but having one draw out a plan does not mean you are on record for doing the work or are committed to having a contractor do it. If it cost a few hundred bucks and you can execute the plan yourself, you may be saving that much in lost attempts or wrong equipment. And there is always the possibility of a hybrid DIY, where you come to an agreement with a contractor to supervise your labor and help where necessary.
nealtw
Contractor retired
Engineers are fine with weights and measures, and they are good at telling you what the end product should look like.
That is why you have to be ready with the plan of your own or anticipate his plan.
They do tell you what size beam the post holding up and the footer below that, Doing the work and how to do it is not his specialty.
If something needs to be pulled or lifted, he can tell you how much it weighs or where the stresses are and can look at equipment and attachment and make suggestions on the specs for those.
That's why I said; have two or three fully buttoned down plans, before you talk to one. Be prepared to argue for the fix you would like to do and make him look stuff up and do the math.
That is why you have to be ready with the plan of your own or anticipate his plan.
They do tell you what size beam the post holding up and the footer below that, Doing the work and how to do it is not his specialty.
If something needs to be pulled or lifted, he can tell you how much it weighs or where the stresses are and can look at equipment and attachment and make suggestions on the specs for those.
That's why I said; have two or three fully buttoned down plans, before you talk to one. Be prepared to argue for the fix you would like to do and make him look stuff up and do the math.
:agree:
Neal is spot on here. If you do the math yourself or he does it the math is the math. When you bring in a contractor he knows his capabilities and if he has a big crane in his shop and a crew of ten guys he won’t think twice about running a 40’ beam down thru your building. A DIY homeowner has a whole different set of capabilities and those form his idea of a best process. One may not be better than another. This job runs the whole range of solutions IMO. The simplest being just stabilize the roof and fortify what is supporting it right where it is at and call it a day.
That is what I did in my garage. It wasn’t worth the money to fix correctly as I could have tore it down and built new for less. It needed a roof but had 4” of swayback in the structure. The Amish guy I hired to put tin on it wanted to jack it back to straight and I said no shim it out to flat and cover it. Inside I had stabilized all the weak points so it wouldn’t get worse and it is sound just not pretty.
This building looks to me to be more worthy of getting it both safe and sound and also looking better. I felt that was the OP’s intent also. And if not perfect at least better. Budget is a big concern when we bought this property a couple years ago I assessed the garage and didn’t like it but the effort and money had to be directed into the house for at least a year and a half. Garages seem to come in second place when the house needs a new kitchen. Women get their way like that. So I did the minimum to keep the garage standing at first and then added the roof in two years to keep what I had done from getting wet. Sometimes you have to do what you have to do.
Neal is spot on here. If you do the math yourself or he does it the math is the math. When you bring in a contractor he knows his capabilities and if he has a big crane in his shop and a crew of ten guys he won’t think twice about running a 40’ beam down thru your building. A DIY homeowner has a whole different set of capabilities and those form his idea of a best process. One may not be better than another. This job runs the whole range of solutions IMO. The simplest being just stabilize the roof and fortify what is supporting it right where it is at and call it a day.
That is what I did in my garage. It wasn’t worth the money to fix correctly as I could have tore it down and built new for less. It needed a roof but had 4” of swayback in the structure. The Amish guy I hired to put tin on it wanted to jack it back to straight and I said no shim it out to flat and cover it. Inside I had stabilized all the weak points so it wouldn’t get worse and it is sound just not pretty.
This building looks to me to be more worthy of getting it both safe and sound and also looking better. I felt that was the OP’s intent also. And if not perfect at least better. Budget is a big concern when we bought this property a couple years ago I assessed the garage and didn’t like it but the effort and money had to be directed into the house for at least a year and a half. Garages seem to come in second place when the house needs a new kitchen. Women get their way like that. So I did the minimum to keep the garage standing at first and then added the roof in two years to keep what I had done from getting wet. Sometimes you have to do what you have to do.
nealtw
Contractor retired
Here is a sample of rafters converted to scissor trusses
nealtw
Contractor retired
They can go up higher and get the same effect..
Good idea. If he covers the ceiling doing that it would look like a gambrel from the inside. :thbup:
nealtw
Contractor retired
There are only two choices. Stiff walls , stiff roof or both.. Lowering the ceiling improves insulation and venting too.
Actually there are three, and since the other two are 20/20 hindsight, this will also be.
The failure is occurring in the middle of the ill-advised and constructed addition above the floor platform, not on the gable ends.
So, had the builder halved the space and built an interior partition wall, with a doorway, the ridge would not be bowing and the wall would not have begone to rotate.
The failure is occurring in the middle of the ill-advised and constructed addition above the floor platform, not on the gable ends.
So, had the builder halved the space and built an interior partition wall, with a doorway, the ridge would not be bowing and the wall would not have begone to rotate.
yep..........
nealtw
Contractor retired
The building is 40 ft so yes it would have been less with a center wall, it would still be a problem non the less, I think
This often shows up in garages and they are only 20 to 25 ft long.
My hindsight analogy is if the builder had put a collar tie at each rafter and thru bolted them or nailed and clinched them. It would have cost a couple hundred bucks more and it would be fine now. If the collar takes the force the knee wall sees none.
