high wind zone & pole barns...

[1Black80Z]

Anyone here build a pole barn in a high wind zone such as that I'm in on the coast of NC? I've been to the permit office several times, and not getting much as to answers. Seems I can never get hooked up with an inspector to talk with...

Just wondering how much more the building would have to be beefed up...

 

[mtwaterguy]

Normally the place you should be concerned is with the roof and it's construction. I used trusses and spec'd 100 mph and 80 lb snow load. In addition, I used a commercial girt installation to give additional protection from racking. It also frames the inside and outside walls at the same time, so I saved on materials and labor.

 

[AlZee]

I built a 36X60 footer in Wyoming. Concerns were wind and snow. Make sure you get an engineer to approve your plans to give you some peace of mind. Also, the builder suggested we turn the building 90% to prevent the prevalent wind from blowing into the main garage doors. We've had no problems but to really tighten things up and stop the dust from blowing in I had it spray foamed. Nice and tight, no worries.

Enjoy your future shop

Al

 

[rieferman]

We have built post-frame at the New Jersey shore where wind load requirements are also very high. As with any style of construction, post-frame can be designed and engineered to different standards. Good luck with your project, pick a good builder

 

[1Black80Z]

I'm in a 130mph wind zone as to building and insurance codes...

and, I'm going to be the builder...

 

[5lima30]

I had two pole barns that I built in Central Florida when I lived there. They are both still standing despite having been through numerous hurricanes during the past 15 years. Use hurricane ties on every truss or rafter end and screw all your metal roofing down. I also like to use additional diagonal bracing on every corner to prevent racking. YMMV.

 

[1Black80Z]

OK...just found out last week I have to use 8"x8" post 8' in the ground, spaced no more than 8' apart...wow...

was hoping to go 6"x6" on the post...

sounds like overkill on a 24'x32' build to me...

 

[ed_v]

OK...just found out last week I have to use 8"x8" post 8' in the ground, spaced no more than 8' apart...wow...

was hoping to go 6"x6" on the post...

sounds like overkill on a 24'x32' build to me...

8ft in the ground?!?!!! Wow.

Ed

 

[little d]

I don't know the specs there but gotta tell ya a story of a friend. The guy builds a machine shed, north side open, does a very nice job. After a storm, his roof is laying behind it. Calls my brother to help him put the roof back on, everything is back in place and lookin good. Next storm....roof is on neibors place, tore all to ****. They both call asking me, wtf? I explained to them that with the open side faceing north (most of our wind comes out of the north), the shop is like a parashute and the weak link is going to give. Told them to use huricane straps on the rafters, still there today.
The point of the story is this; What seams like over kill to build the first time is nothing compared to haveing to rebuild it a second time, D.

 

[1Black80Z]

yup...8' in the ground...

I have no way to set post 8' in the ground...I would have to hire that out...$60 per post plus $100 for the cost of the post...that's nuts..

I tried to counter the demand by going 6"x6", six foot in the ground on four foot centers...no go...

 

[NASMAN]

OK...just found out last week I have to use 8"x8" post 8' in the ground, spaced no more than 8' apart...wow...

was hoping to go 6"x6" on the post...

sounds like overkill on a 24'x32' build to me...

If that is the what the regulations require than that is what they require. And you are screwed. That is totally dumb. How do they require a house to be attached to mother earth. If you were to build a building on a slab what do they require?
Perhaps you could build it on a slab with tiedowns in the pour and attached to the posts up the post for 24 inches. Just a suggestion. Agree with the others, use straps (tie downs) on every thing.
We are not in a high wind zone, but we are in a tornado zone. It is impossible to build and be sure that a tornado will not take it down. However we do the best that we can to prevent anything but a direct hit from causing damage.
The size that you are wishing to build is also the same size as ours. The posts at every eight feet on that size works out real well. We used 6 x 6 posts but we are very rural here and don't have a code prroblem.
Check us out on the GJ link on on our web site below. Hope it will be of some help to your build, and good luck.

 

[WNYflyer]

A majority of the country has a design wind speed of 90 MPH. As you stated your design wind speed is 130 mph because of being near the coast.

Increasing the design wind speed to 130 mph from 90 mph essentially increases the wind forces on your building by approximately 2x's as compared to a 90 mph area. The wind forces vary with the square of MPH. Thus (130x130)/(90x90) = 2.10. This will give you an idea of why the increased post size and embedment in the ground and the decreased post spacing.

 

[mtwaterguy]

I think I'd be more concerned with the 8" spacing. 8' less the posts and any bracketry for a door, how are you supposed to get anything in it?

 

[cyamaha2007]

^^^^ Im sure that is 8ft spacing on side walls. The gable ends on a pole building are not weight bearing. Think of a pavilion. You can dig 8ft down by hand get a set of utility co pole diggers. Those things could dig a 24in hole 12ft down.

 

[ishiboo]

This doesn't sound that extreme to me, the building is 32'... so that would be a total of 4 posts per long side. I wouldn't do any less than 4 posts on a 32'.

$1280 for the posts and drilling does not seem all that bad.

 

[1Black80Z]

This doesn't sound that extreme to me, the building is 32'... so that would be a total of 4 posts per long side. I wouldn't do any less than 4 posts on a 32'.

$1280 for the posts and drilling does not seem all that bad.

your forgetting your starting post...that's 5 to the side...plus, they want two more on each end, with a engineered header above the garage door if it spans more than 8'...

 

[1Black80Z]

^^^^ Im sure that is 8ft spacing on side walls. The gable ends on a pole building are not weight bearing. Think of a pavilion. You can dig 8ft down by hand get a set of utility co pole diggers. Those things could dig a 24in hole 12ft down.

I'm at 5' above sealevel...anything deeper than 4' I'm in water..tough digging when the sides collapse and fill in what you just dug...not trying to kill myself digging holes...LOL...

 

[cyamaha2007]

Well i could see that being a problem. My post holes caved in if i was hit with any rain. I did find a way to "stabilize" a loose hole. Throw some quickcrete on the walls of the hole it really helped with caveins. I hope you are able to find a cost effective way to build your building.

 

[Highbeam]

Who told you 8' deep? Who is the ****** that wants a header on the gable end of a pole barn? You're dealing with a green gov't worker or a stupid CYA engineer.

I'm calling BS. Either the person that told you this doesn't understand what they're saying or they gave you options and one of them included burial to 8'. Thing is, only thing you gain from 7-8 feet is additional uplift protection. Rather than the extra depth, you could do something else to resist uplift such as concrete backfill. Burial depth over 1/3 of the height of the wall is of no benefit to side wind loads.

I built my pole barn in a high wind zone. 115 I believe and the rest of my county is 80mph. The controlling load was the side load from the wind on my 14 foot tall sidewalls. I had to use true 6x8 posts four feet deep, only number 1 grade doug fir which is not common, and then knee braces. My post and truss spacing is 12 feet.

You need your own engineer that can interpret actual codes in your favor.

 

[KANSASBOY]

You my what to check around see what it would cost to post driven in because of the hi water table . like they do on boat docks .

 

[1Black80Z]

Who told you 8' deep? Who is the ****** that wants a header on the gable end of a pole barn? You're dealing with a green gov't worker or a stupid CYA engineer.

I'm calling BS. Either the person that told you this doesn't understand what they're saying or they gave you options and one of them included burial to 8'. Thing is, only thing you gain from 7-8 feet is additional uplift protection. Rather than the extra depth, you could do something else to resist uplift such as concrete backfill. Burial depth over 1/3 of the height of the wall is of no benefit to side wind loads.

I built my pole barn in a high wind zone. 115 I believe and the rest of my county is 80mph. The controlling load was the side load from the wind on my 14 foot tall sidewalls. I had to use true 6x8 posts four feet deep, only number 1 grade doug fir which is not common, and then knee braces. My post and truss spacing is 12 feet.

You need your own engineer that can interpret actual codes in your favor.

just passing what I was told by a senior inspector before I apply for a permit...no option on the 8' deep post...and nothing less than 8"x8", period.

 

[1Black80Z]

You my what to check around see what it would cost to post driven in because of the hi water table . like they do on boat docks .

yeah, I have thought of building a platform to hold the post up and washing them down...

 

[Charles (in GA)]

You need an engineer to design this. If they design to code the inspectors will probably approve it no matter what. Inspectors are prone to tell individuals different than what the code actually says, sometimes to discourage individuals from designing on their own, sometimes because they do not understand the code.

You are much better off walking in with stamped drawings in hand to get the permit.

Charles

 

[1Black80Z]

You need an engineer to design this. If they design to code the inspectors will probably approve it no matter what. Inspectors are prone to tell individuals different than what the code actually says, sometimes to discourage individuals from designing on their own, sometimes because they do not understand the code.

You are much better off walking in with stamped drawings in hand to get the permit.

Charles

looking into this now...