Pole Barn - Why not use center post?

gabeancounter · Feb 12, 2011

Green,
My original questions was based off the framing method below. You did not read the post or assumed you knew what was being requested. I have never said anything about using a ridge beam or spanning 2x8's 30'. Two rafters from outside post to center post , then place vertical purlins. This was a very popular method before the clear span truss method.
Please see website. How To Build a Pole Barn...Secrets and Shortcuts

Also I did speak with the inspector. Again you did not read any of the post. I don't need a crew of engineers to build a dang pole barn.

blueriver · Feb 12, 2011

gabeancounter said:
Green,
My original questions was based off the framing method below. You did not read the post or assumed you knew what was being requested. I have never said anything about using a ridge beam or spanning 2x8's 30'. Two rafters from outside post to center post , then place vertical purlins. This was a very popular method before the clear span truss method.
Please see website. How To Build a Pole Barn...Secrets and Shortcuts

Also I did speak with the inspector. Again you did not read any of the post. I don't need a crew of engineers to build a dang pole barn.

Well said ...

Green_in_Michigan · Feb 12, 2011

blueriver said:
Well said ...

Fine, no reason for you guys to get all pissy about it.

MarkV · Feb 12, 2011

gabeancounter said:
Green,
My original questions was based off the framing method below. You did not read the post or assumed you knew what was being requested. I have never said anything about using a ridge beam or spanning 2x8's 30'. Two rafters from outside post to center post , then place vertical purlins. This was a very popular method before the clear span truss method.
Please see website. How To Build a Pole Barn...Secrets and Shortcuts

Also I did speak with the inspector. Again you did not read any of the post. I don't need a crew of engineers to build a dang pole barn.

So be it! Why ask for help then? You have already decided what you want, know more than those who have been there and checked with your local inspector. What is the purpose of your post then?????

MarkV

JimRB · Feb 12, 2011

While you might think that a pole barn is no big deal, many counties in Georgia do not want to see lick and a promise structures going up. It brings down property values in the county, county does not want any liability for allowing an underengineered building to go up and don't want the hassle of making someone take down an unsafe building they just put up.

Morton uses pressure treated laminated poles consisting of 2x6 PT lumber. Not sure what the rating is but I would guess .40 which used to be a number that represented ground contact. PT also has some termite resistence. White wood in the ground will get eaten up by termites in a few years or will rot in the same few years. Even with some black paint which offers no protection. Just cut a pine tree down in Georgia and leave that stump there. In 5 years you will be able to kick that stump away because of rot or termites.

I have not seen 3' on center in Georgia but I have looked at houses which seem to be 2' or less OC. We do have snow load in Georgia. In the past two years we have had up to 6 inches of snow in Athens. A 4/12 roof does not shed that snow that quickly. My 9/12 roof did not shed that snow that fast either. I have seen a variation of that framing your picture shows but it has been a few years since I visited my friends place. They do have leaks.

BobRip · Feb 13, 2011

If you plan to store things in the trusses, you should consider storage trusses. I have them in my garage and it gives me a nice room in the attic.

gabeancounter · Feb 13, 2011

JimRB said:
While you might think that a pole barn is no big deal, many counties in Georgia do not want to see lick and a promise structures going up. It brings down property values in the county, county does not want any liability for allowing an underengineered building to go up and don't want the hassle of making someone take down an unsafe building they just put up.

Morton uses pressure treated laminated poles consisting of 2x6 PT lumber. Not sure what the rating is but I would guess .40 which used to be a number that represented ground contact. PT also has some termite resistence. White wood in the ground will get eaten up by termites in a few years or will rot in the same few years. Even with some black paint which offers no protection. Just cut a pine tree down in Georgia and leave that stump there. In 5 years you will be able to kick that stump away because of rot or termites.

I have not seen 3' on center in Georgia but I have looked at houses which seem to be 2' or less OC. We do have snow load in Georgia. In the past two years we have had up to 6 inches of snow in Athens. A 4/12 roof does not shed that snow that quickly. My 9/12 roof did not shed that snow that fast either. I have seen a variation of that framing your picture shows but it has been a few years since I visited my friends place. They do have leaks.

Jim,
Thanks for your post. I know there is a lot of different questions in my post and different methods. My original questions were based off the picture above. Then I started asking questions about trusses because nobody had any input on this method.

First, I have never said anything about using white wood with black paint. This was another poster that did not read the thread and suggested I said that. Every post I have mention said 2x6 PT or pressure treated. My question about the black paint was using on STANDARD PRESSURE TREATED. As you will not find ground contact PT in the big box stores without special ordering.

I don't understand your comment about "They do have leaks"? How does this have anything to do with framing?

Last I have no intentions of putting up some hope and prayer building. My questions were to inquiry on the method of framing instead of trusses as I don't need a clear span building.

JimRB · Feb 13, 2011

The leaks might be because the plywood deck is spanning wider than a 2' span which the plywood might not be rated for. Crummy framing can make it impossible to not have leaks. Just like a bad flashing job often causes leaks. Watch that Holmes fellow from Canada doing remodel repair shows on cable if you want to see a hundred ways to do a job the wrong way. No not the way Holmes does things but all the screwups he turns up.

If you are serious about building you do not go to Home Depot or Lowes for framing materials. You go to a lumber yard. The lumber yard that supplied my barn and the one that supplied my house are gone but there are still 2 good lumber yards within 15 miles of my house. Or if you know what you want you have Lowes or HD order what you need. When I built my pole barn I bought 6x6 PT 16' and 20' long. I dug holes and picked them up and tipped them in the holes by hand. It sounds like you can do that but the inspector wants to see what you put in the holes. My inspector didn't seem to care but that was 13 years ago.

LD1 · Feb 14, 2011

JimRB said:
The leaks might be because the plywood deck is spanning wider than a 2' span which the plywood might not be rated for. Crummy framing can make it impossible to not have leaks. Just like a bad flashing job often causes leaks. Watch that Holmes fellow from Canada doing remodel repair shows on cable if you want to see a hundred ways to do a job the wrong way. No not the way Holmes does things but all the screwups he turns up.

If you are serious about building you do not go to Home Depot or Lowes for framing materials. You go to a lumber yard. The lumber yard that supplied my barn and the one that supplied my house are gone but there are still 2 good lumber yards within 15 miles of my house. Or if you know what you want you have Lowes or HD order what you need. When I built my pole barn I bought 6x6 PT 16' and 20' long. I dug holes and picked them up and tipped them in the holes by hand. It sounds like you can do that but the inspector wants to see what you put in the holes. My inspector didn't seem to care but that was 13 years ago.

I am going to have to disagree with about everything you just said.

First, I believe to OP never made mention about using plywood. He is probabally going to use steel like 99% of pole barns today use.

Second, he never said anything about spanning more than 2' either. He said the purlins were GOING to be 2' appart, so I dont know how you got more than that.

And finally, the comment about "if you are serious, you dont go to a box store" kinda pieves me. What is the difference between a SYP 2x8 at lowes vs at a lumber yard??? The only difference that I have found is that the lumber yard thinks they are worth twice as much.

Their is absolutly nothing wrong with buying building material from HD, lowes, menards, etc. And no thanks on the special order or deliver either. I will pick the lumber I want off the rack. That way I know what I am getting.

To the OP: I see nothing wrong with framing the way they show in the pictures. Just be sure you size the lumber accordingly. Their are plenty of usefull charts and calculators online. The "purlins" that are going to be ran parallel with the ridge line will be easy to figure based on span. But the MAIN rafters these tie to may be a little more channenging. You have to factor the loads that are going to apply over the given span and treat it as a "BEAM" and NOT a rafter. Because most sizing tables for rafters only go up to a 2' span. And you are talking on the order of 10-15 feet. Personally, for peice of mind and it shouldnt cost much, consult a PE in your area. Take a pic like the one you posted. Give him sizes and spans and ask him how big the lumber needs to be. Maybe a 2x12, or a double 2x12, who knows. But get a PE's advise in that area and you will sleep better at night. That is of course if you choose not to use trusses or traditional rafters.

gabeancounter · Feb 14, 2011

LD1,
You are correct on all spects of your reply. Did not want to keep saying "I did not say this or that" anymore. I do intend to use metal roofing.

I was thinking the mains would either be 2x10 or 2x12 and 2x8 purlins. I agree I need to get a little more info and that was the point of the post. Thanks for the reply.

LD1 · Feb 14, 2011

gabeancounter said:
LD1,
You are correct on all spects of your reply. Did not want to keep saying "I did not say this or that" anymore. I do intend to use metal roofing.

I was thinking the mains would either be 2x10 or 2x12 and 2x8 purlins. I agree I need to get a little more info and that was the point of the post. Thanks for the reply.

Just at first glance, I dont think 2x10 or even a single 2x12 will be enough for the mains. Pitch doesnt matter. You look at the horizontal span. Which will be 15' in your case if you are going 30' deep.

So basically you need to look at this like a floor, with the "main rafters" being the beams, and the horizontal purlins being the floor joists.

I am not sure what you need for "beams", and I am not sure how far appart they will be, But again, just at first glance, if 2x8's every 2' are needed for the purlins, I think something a bit stouter than even a single 2x12 is needed.

Just rambling here but see if you can follow....If you plan on spacing them 10' appart, Each beam will have to hold up 150 sq ft of roof. (5' each side which is 10' x 15' deapth to ridge beam). This is figured in a horizontal plane.

Now probabally the lowest code an engineer would let you get away with would be a 5psf dead load and a 20psf live load. Total of 25 lbs per sq foot. So, 25x150 is 3750 lbs evenly distributed that must be supported by EACH "beam" or "Main Rafter" AND span the 15'. This is the area I suggest to contact a PE for approval. And definatally as already mentioned, check to see if there is any laws or codes you MUST follow for your area.

Sizing the purlins is simple.

And one other thing you might want to check on... I am not sure where in GA you live, but I bet you get some wind. So think about your attachment points. With the method of building you picture, their are fewer attachments points holding the roof structure to the walls.

gabeancounter · Feb 14, 2011

LD1,
I follow your logic. It appeared to me in the picture I posted that the board size for the purlins was 2x6. The mains look around 2x8 or 2x10. I thought I was using overkill by 2x8 purlins and 2x10 or 2x12 mains.

I figured I could get some input to this method on this site before spending $15 on the download for the "secerts". But if the board spacing and sizing is that far off , then it will cost as much as using trusses.

gabeancounter · Feb 14, 2011

This is one of the few that seems to be using a similar build design. Now his spacing is around 12' I think. My design was similar just not the center section. This is steeldust photo from his thread.

LD1 · Feb 14, 2011

gabeancounter said:
This is one of the few that seems to be using a similar build design. Now his spacing is around 12' I think. My design was similar just not the center section. This is steeldust photo from his thread.

It looks like you are close with the spacing @ around 12', BUT, it doesnt look anywhere near a 15' span though. It looks like maybe 10' at the most.

AND it is hard to tell, but it looks like the middle sections are a DOUBLE 2x12. See pic.

The middle two "beams" will have to support twice the load as the end beams. Because they have to support the roof on BOTH sides half way to the next beam. The end beams only are supporting roof on the one side, not counting a small overhang.

gabeancounter · Feb 14, 2011

Off topic. I just noticed that it looks like his kid is laying in a stroller while he is working on his barn?? Too funny.

Not sure about his spacing, but it looks very sturdy. I think I will re-read your thread as I found out over the weekend that I think the covenants will require it be enclosed. How much did you have invested in your build?

LD1 · Feb 14, 2011

gabeancounter said:
Off topic. I just noticed that it looks like his kid is laying in a stroller while he is working on his barn?? Too funny.

Not sure about his spacing, but it looks very sturdy. I think I will re-read your thread as I found out over the weekend that I think the covenants will require it be enclosed. How much did you have invested in your build?

I just noticed the stroller too:laughing::laughing::laughing: Maybe the horses were watching the little one:thumbsup:

To answer your question, I have probabally ~$10k invested. That is as current with: electrical, concrete, loft, insulation, etc.

Since I used electric poles, that saved a ton on cost. But JUST the basic framing material I bought to get the trusses up and the walls built was ~ $1000. Metal was the expensive part. I cant remember off the top of my head, but it is around $3k in metal. So I was at ~$4k to get it under roof. That was nothing extra, no doors, and just open on one side.

JimRB · Feb 14, 2011

If HD/Lowes does not have the lumber you need sitting in their racks what do you do? I wanted 2x8 20' long. Lumber yard had it. I wanted 16' and 20' 6x6. Lumber yard delivered it at a good price. I am about as cheap as many others and would not be going to a lumber yard to pay more. But I do sometimes place a value on my time. At least the counter help at the lumber yard knows what I am asking for. Of course some of the guys at Lowes and HD know their stuff too.

Here is one thought to the original poster. A greater/longer overhang on all sides can reduce the amount of splashing on the exterior walls. If you have open sides it might reduce some of the water that blows in although with our storms I have seen water blow in 10 feet when our 10' tall doors are left open.

Johnbro · Feb 15, 2011

gabeancounter said:
Green,
I don't need a crew of engineers to build a dang pole barn.

LOL. well said.

I think trusses are MUCH easier than rafters. I made my own trusses for a wood shed, and the next time I'll just buy the suckers. I made a jig on the floor to hold the pieces (which were all pre cut on my chopsaw), then glued and nailed plywood gussets down to hold everything in place. I would have used those metal pound plates, but the ones at the local HD said clearly "Not for trusses." so I didn't. Besides, I'm cheap:laughing:

Cutting rafters isn't rocket science, but there are at least 3 or 4 ways to screw it up and then what do you have? A bunch of 2X lumber that's too short. Plus, maybe your lumber is better than our lumber, but even when I buy 16 foot 2x8 or 2x10s from teh GOOD lumber yard (Dunn Lumber) finding enough that are nice and straight is tough. And placing them is a pain compared to trusses--the only thing important placing trusses is to get them aligned top and bottom--mark off your top plates at 24"OC or whatever your spacing is. Then take some 1x4 and mark it exactly the same. Use the 1x4 as a temporary support nailed along the top sides of the trusses to hold them vertical until you can put sheathing down.

With rafters, you sort of have to use collar ties to keep the downward pressure of the roof from spreading the sides of your building apart. So now you've got three pieces of wood (two rafters and a collar tie). Might as well buy trusses!

gabeancounter · Feb 15, 2011

Johnbro,

I agree. But looking at that framing picture it sure does look easier and cheaper than building with trusses. I think I maybe converted to trusses, now the diy or store version is in the air.

Jim,
I understand all to well about lumber yards. I have an account with Social Circle Ace and 2 years ago when I was building my house I purchased around $100k of products from them. Everyday pricing will have many of the yards cheaper than HD, but on certain items like when OSB goes on sale or when you have 10% coupons and can get 2x8x16 for $7.25 the yards can't match it.
Now as far as quality of lumber, I have not seen any better lumber from the yards compared to big box. You are correct in the quality of service and ease of delivery. I pay $5 for delivery no matter if it is a single board or a tractor trailer load and it is always same day if ordered that morning.
I assume you used Plymart on Alcovy or 84 lumber on 278 since they are now "out of business". I tried both of those yards and the economy had already taken its toll on them long before they shutdown.

JimRB · Feb 15, 2011

gabeancounter said:
Johnbro,

I agree. But looking at that framing picture it sure does look easier and cheaper than building with trusses. I think I maybe converted to trusses, now the diy or store version is in the air.

Jim,
I understand all to well about lumber yards. I have an account with Social Circle Ace and 2 years ago when I was building my house I purchased around $100k of products from them. Everyday pricing will have many of the yards cheaper than HD, but on certain items like when OSB goes on sale or when you have 10% coupons and can get 2x8x16 for $7.25 the yards can't match it.
Now as far as quality of lumber, I have not seen any better lumber from the yards compared to big box. You are correct in the quality of service and ease of delivery. I pay $5 for delivery no matter if it is a single board or a tractor trailer load and it is always same day if ordered that morning.
I assume you used Plymart on Alcovy or 84 lumber on 278 since they are now "out of business". I tried both of those yards and the economy had already taken its toll on them long before they shutdown.

Covington Plymart for house, Covington 84 for a shed, some other yard in Lithonia for the barn. All three lumber yards are gone. I did send back a fair bit of cull. When building the house I spent 2 days pulling crummy studs out of the house after the framers left. Actually more like two man days as some friends helped me do the framing cleanup. Yes all sources have some crummy lumber that may need to be culled. I did use HD in Conyers for lots of stuff as there was no HD in Covington. Social Circle Ace seems like a good yard which would be on my list if I was doing another big project. I hope I can build a new tractor shed in 5 years but I have bills to pay now.

My wife has code in her web page to kill linking to this page but if you cut and paste you can read the silly tale of me building my pole barn for horses. Pole Barn Building I did another pole barn with my barn electrician as a labor swap. Instead of getting the poles 1/2" out corner to corner I got that second pole barn dead on. We did trusses for a huge clear span on the electrician's barn. He called a light bucket truck friend to help set those trusses. Pole building can be fun but next shed is going to be stick built on a concrete pad or maybe metal framed depending on which material makes the most sense price wise.