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Discussion Starter #1
I've been looking at small pole building engineering. It appears that if you use poles set at 8' apart or greater, you need to use a truss built roof rather than common rafters. I'm looking at buildings & IRC codes that indicate you can go as wide as 12' between poles. But everything I read says "Truss" built roofs when post are at 8'+. I'm thinking of a barn 18' x 24'. I wanted to use 8' spacing over 6x6 poles. But I do not want to use trusses. So now I'm looking at 6' spacing. Has anyone done a barn around the size I'm thinking about using 8' between poles with a common rafter roof build. :question:

I hope my question is understandable. :dunno:
 

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I will look in my code books. I think it is more a function of the beam size running between posts and the bracing between posts than the post size. The oak barn I built used 7x7's and the spacing was 12'. I would avoid a truss roof at all costs.99% of all the roof failures up here in the snow this winter were truss roofs. I think you are going to see some code revisions coming.
 

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My building was erected in 1992, it has 8 foot pole spacing with trusses. I are starting to spread a lot of weight out on rafters. Think of any additional snow load and you may have a mess. What is your reason not use trusses?
 

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More useable space, no crane, save money, better looking, less expensive to upsize for extra load, do it all your self, and trusses typically would be spec'd for a wider span where conventional framing might be more difficult for some. JMTC
 

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I will look in my code books. I think it is more a function of the beam size running between posts and the bracing between posts than the post size. The oak barn I built used 7x7's and the spacing was 12'. I would avoid a truss roof at all costs.99% of all the roof failures up here in the snow this winter were truss roofs. I think you are going to see some code revisions coming.
Not sure the OP has concerns about snow load in SC? Maybe should place some strapping for uplift from hurricane winds depending on his location though...:unknown:
 

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I don't think he is worried about snow either. Back before the engineers and the lumber company's got involved in roof designs people built for functionality and practicality and usually overbuild a little just because. Given a choice on a small span building I would opt for an open attic area with some properly installed collar ties and maximize the usable space. With the right size header/beam between posts that are properly braced any spacing is possible.
 

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I will look in my code books. I think it is more a function of the beam size running between posts and the bracing between posts than the post size. The oak barn I built used 7x7's and the spacing was 12'. I would avoid a truss roof at all costs.99% of all the roof failures up here in the snow this winter were truss roofs. I think you are going to see some code revisions coming.
As Manomet has stated, it is the beam size (weight to be carried), bracing, post size and footings that will determine how far apart the support posts can be. We are both building officials about 35-40 miles apart and I have also witnessed destruction with trusses and hardly any failures with conventional rafters, plus fire hates trusses, the gusset plates melt off before the wood even really gets going, less chance to save the structure, and regular trusses are not designed to store anything on the lower cord. You can order limited storage trusses but $$$$. Your support beam size will also need to be beefed up if you plan to store anything on the ties or ceiling joists. With the proper beam size, post size, footings, wall ties (ceiling joists) or collar ties located in right place and not the upper 1/3 area (you can use mechanical fasteners over the top of the rafters to tie the upper third of the rafters), the sky is the limit for you. I would not want to get into the IRC if you are not familiar with the charts, math and wind bracing so I would contact a local design engineer and have that person do the calcs/design for you. If you need a permit you will no doubt need a plan and the official will be looking for calculations. It would be cheap money to have a professional design your barn. Unfortunately here in Ma we have &%#* amendments to go along with the IRC! Good luck
Jeff
 

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Discussion Starter #9
My building was erected in 1992, it has 8 foot pole spacing with trusses. I are starting to spread a lot of weight out on rafters. Think of any additional snow load and you may have a mess. What is your reason not use trusses?
To answer your question on avoiding trusses. I will be building this on my own, with no help. Also cost of having trusses engineered & built. I would have to hire a few helpers, probably three guys & myself to stack em & place em. My current lumber estimate for a 18' x 24' barn-PLUS a left & right side shed attached to the main building that measure 12' x 24' is running $3,624. for what is essentially three structers- a main barn, a storage shed & a workshop shed. This figure is pretty complete as far as major lumber & siding goes. Does not include finish roofing such as shingles or metal. And I want a concrete floor pour as well.

The current plan calls for 6x6 posts spaced six feet apart on the 24 foot measure. This puts a post right in the center of the building on either side. This now allows the ceiling or loft joists to run in the same direction as the wall. At the center posts a double 2x8x18' span across the width of the building & the joists tie into that 2 x 8 which shortens the joists to a 12' length on either side of the 18 foot span beam. Hope I'm explaining it good enough here. This is not my design. However it is a plan done by a licensed architect & I like it. But what I am trying to do is change it in order to possibly eliminate a couple of poles, their cost & the work but it does not appear to be worth it.

This lead me to do some research & I noticed that everything I looked at indicated to go to a truss roof when pole span is at or over 8' wide.
I really don't understand that. This building is only 18'x24' & really in no need of trusses. As a one man builder I can put up a gable roof on my own. I've done it before & with good prep for the ridge beam & pre cut common rafters, I can erect it by myself as I've done it in the past.

Having said all this, I'm somewhat committed to the architect's use of six foot between poles. The reason being that the loft joists run on the same plane as the walls, but are 12' long because they tie into the 18' span header. The other option would be to run the joists at a right angle to the walls. This would require 18 foot long joists- and a lot of bracing to stiffen them up along with possible sagging problems later on.

And lastly, whatever money & work I save on pole elimination will be lost on all the additional lumber & work needed to do it differently. But again, I'm curious as to why everyone is saying "Truss" at 8' & over. It rarely snows here in this part of the state. And when it does, it's gone in a few hours. We get more frost & black ice than snow. I believe that structures should b built as required by their use & the environment they will be in. So that's why I'm questioning this blanket statement roof trusses. I have nothing against trusses provided that they are necessary & not overkill to what you really need. Thanks for reading my mindless babble.

:knownothing:
 

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To answer your question on avoiding trusses. I will be building this on my own, with no help. Also cost of having trusses engineered & built. I would have to hire a few helpers, probably three guys & myself to stack em & place em. My current lumber estimate for a 18' x 24' barn-PLUS a left & right side shed attached to the main building that measure 12' x 24' is running $3,624. for what is essentially three structers- a main barn, a storage shed & a workshop shed. This figure is pretty complete as far as major lumber & siding goes. Does not include finish roofing such as shingles or metal. And I want a concrete floor pour as well.

The current plan calls for 6x6 posts spaced six feet apart on the 24 foot measure. This puts a post right in the center of the building on either side. This now allows the ceiling or loft joists to run in the same direction as the wall. At the center posts a double 2x8x18' span across the width of the building & the joists tie into that 2 x 8 which shortens the joists to a 12' length on either side of the 18 foot span beam. Hope I'm explaining it good enough here. This is not my design. However it is a plan done by a licensed architect & I like it. But what I am trying to do is change it in order to possibly eliminate a couple of poles, their cost & the work but it does not appear to be worth it.

This lead me to do some research & I noticed that everything I looked at indicated to go to a truss roof when pole span is at or over 8' wide.
I really don't understand that. This building is only 18'x24' & really in no need of trusses. As a one man builder I can put up a gable roof on my own. I've done it before & with good prep for the ridge beam & pre cut common rafters, I can erect it by myself as I've done it in the past.

Having said all this, I'm somewhat committed to the architect's use of six foot between poles. The reason being that the loft joists run on the same plane as the walls, but are 12' long because they tie into the 18' span header. The other option would be to run the joists at a right angle to the walls. This would require 18 foot long joists- and a lot of bracing to stiffen them up along with possible sagging problems later on.

And lastly, whatever money & work I save on pole elimination will be lost on all the additional lumber & work needed to do it differently. But again, I'm curious as to why everyone is saying "Truss" at 8' & over. It rarely snows here in this part of the state. And when it does, it's gone in a few hours. We get more frost & black ice than snow. I believe that structures should b built as required by their use & the environment they will be in. So that's why I'm questioning this blanket statement roof trusses. I have nothing against trusses provided that they are necessary & not overkill to what you really need. Thanks for reading my mindless babble.

:knownothing:
Maddog, I am at a loss on the; "over 8' span requires trusses"? I don't know where that comes from. You can use the 18' span and beef up the joist similar to a truss by tying to the rafters in the right places to stop the "sag" as you put it.. This is very simple to do, yes a few more sticks of lumber but you will get what you want. 2- 2X8X18' with the joists running 12' will have quite a bounce on the floor/loft area..
It is the beams/headers between the posts that need to be beefed up to get a larger span between the posts.. It appears you want to just have an opening in the center of the wall, in that case just beef up that span and leave the rest at the 6 spacing. It will save you a few bucks. I don't see any law that requires trusses for this size building.. Trusses are for ease and speed of building in this case but not mandated by code. Hope this helps.. Jeff
 

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My building was erected in 1992, it has 8 foot pole spacing with trusses. I are starting to spread a lot of weight out on rafters. Think of any additional snow load and you may have a mess. What is your reason not use trusses?
And I am just as jealous as the next guy when I see your beautiful shop.
 

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Discussion Starter #12
Maddog, I am at a loss on the; "over 8' span requires trusses"? I don't know where that comes from. You can use the 18' span and beef up the joist similar to a truss by tying to the rafters in the right places to stop the "sag" as you put it.. This is very simple to do, yes a few more sticks of lumber but you will get what you want. 2- 2X8X18' with the joists running 12' will have quite a bounce on the floor/loft area..
It is the beams/headers between the posts that need to be beefed up to get a larger span between the posts.. It appears you want to just have an opening in the center of the wall, in that case just beef up that span and leave the rest at the 6 spacing. It will save you a few bucks. I don't see any law that requires trusses for this size building.. Trusses are for ease and speed of building in this case but not mandated by code. Hope this helps.. Jeff
I understand that the wider the distance between poles will require beefed up top band or girts & top plate. And your correct, in that I was interested in opening up the distance between poles to more or less give me a little more room in the building. While it may not be a "law" everything I'm reading keeps referring back to Trusses on poles over 8'. Like you I don't understand where that's coming from either.

Regarding any "bounce" in those 12' joists, I don't think there will be any. I know someone who built this barn off the same set of plans that I have. He followed everything on the plan & he is reporting to me no bounce or vibrations at all. I did fail to mention that blocking is used between the joists. Thanks!
 

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I understand that the wider the distance between poles will require beefed up top band or girts & top plate. And your correct, in that I was interested in opening up the distance between poles to more or less give me a little more room in the building. While it may not be a "law" everything I'm reading keeps referring back to Trusses on poles over 8'. Like you I don't understand where that's coming from either.

Regarding any "bounce" in those 12' joists, I don't think there will be any. I know someone who built this barn off the same set of plans that I have. He followed everything on the plan & he is reporting to me no bounce or vibrations at all. I did fail to mention that blocking is used between the joists. Thanks!
The bounce I was referring to would be the beam (2-2x8x18') that is carrying the 12' floor joists on both sides of the beam, but that all depends on what you want to store up there. I would beef that beam up to 2- 2X12" but that's just me, you could also do a flitch plate beam with the 2x8's. Good luck, and the truss thing is not code nor law and if you ever find where that comes from please let me know for my own education.. 42 years in construction and this is a new one on me.. Here you would have to get that beam engineered, but Mass is pretty strict and inspectors are fair game for attorneys! It would be; "that guy let me build it like this and it failed".. You are now fired and have a personal law suit on your hands!!! Right Manomet!
Have fun with your project... Has me thinking of a spring project myself! But I already have to may structures and high real-estate taxes!!!
Jeff
 

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I didn't think 2x8's were good for spanning any distance and be expected to support a load?
 

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Discussion Starter #15
The bounce I was referring to would be the beam (2-2x8x18') that is carrying the 12' floor joists on both sides of the beam, but that all depends on what you want to store up there. I would beef that beam up to 2- 2X12" but that's just me, you could also do a flitch plate beam with the 2x8's. Good luck, and the truss thing is not code nor law and if you ever find where that comes from please let me know for my own education.. 42 years in construction and this is a new one on me.. Here you would have to get that beam engineered, but Mass is pretty strict and inspectors are fair game for attorneys! It would be; "that guy let me build it like this and it failed".. You are now fired and have a personal law suit on your hands!!! Right Manomet!
Have fun with your project... Has me thinking of a spring project myself! But I already have to may structures and high real-estate taxes!!!
Jeff
I can't really argue with anything you are saying. As far as the Truss thing goes, It is what I am finding as I do some research. Remember, its not me saying you need trusses. I'm just as curious as you why most of the advice given is directing the use of trusses. Maybe its because the feeling is that the amateur DIY guy can't cut common rafters properly? I don't know.

I went to our county municipal dept. today to inquire about permits & inspections. I was told that since I'm building on a residential property
(I have 4.14 acres here) I will need inspections. Then I explained that it was for tractor & tool storage & the size was about 1,000 square feet. I also explained that I could not find any references being made to IRC code requirements regarding a storage building. The clerk looked up my property records & told me that when I'm ready to pull the permit, I will need to file an application with basic construction information filled out. Permit will be issued at that time. She indicated to me that there should be two inspections only conducted for a "Pole & Beam" construction. First inspection should be called for when I have all holes dug & ready for a footing pour. The second & final inspection would be after the building is all framed. She added that since a Pole building is essentially nothing but framing, that would be it on inspections. What else can they inspect? No CO being issued. Unless my JD need one.

We are no longer required to present or file drawings on many building here including homes that will be occupied. I just finished building my home here 13 months ago. We had inspections taking place between the contractor & the inspector. But no one from the county ever asked to see the drawings, so I guess everything the contractor was doing satisfied the inspector. I do know my contractor did a lot more work than what was call for on the plans when it came to the foundation & the roof framing.

My concern is, that if no one wants to see the plans or ask questions, what position am I left in if I have the framing inspection after completion & the inspector decides he doesn't like something? We have rules & regulations here too. But when your outside the city or town limits and your neighbor is 5 acres down the road & has a yard full of goats, a pony & a pet Cow, no one really gets excited about a storage barn. In the field across the road from me there's usually two or three people shooting clay targets & no one gets their shorts in a bunch over it. I'm just rambling on here. But I might be living in the last place in America where we are still trying to hold onto the true spirit of America.

:usa:usa:usa:usa:usa:usa:greentractorride:
 

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Discussion Starter #16
I didn't think 2x8's were good for spanning any distance and be expected to support a load?
If I got it right, the IRC codes allow it. It's difficult to understand the language in some of the codes. But here is what IRC state about load bearing headers on Gable end wall openings: 10 feet wide-requires 2-2x8 -12 feet wide 2-2x10 & 16 feet wide 2-2x12's as headers above doors.

Some sections of the IRC code state that you cannot have spans more than 8' between cols. Well that's nuts too because I just stated above door openings up to 16 feet wide. The major problems that I see for the average dope (me) is one of code interpretation. This is a Major problem because IRC always wimps out by saying final determinations are left entirely up to the municipal authorities. So if I happen to get an inspector who has no engineering background or who does not understand small building engineering, or is not equipped to make fairly complex calculations, I could be screwed if he decides to not be reasonable or not understand building basics. :banghead:

I just love it when someone is protecting "me" from "me". I thought I had a wife to do that.:yahoo::lolol:
 

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If I got it right, the IRC codes allow it. It's difficult to understand the language in some of the codes. But here is what IRC state about load bearing headers on Gable end wall openings: 10 feet wide-requires 2-2x8 -12 feet wide 2-2x10 & 16 feet wide 2-2x12's as headers above doors.

Some sections of the IRC code state that you cannot have spans more than 8' between cols. Well that's nuts too because I just stated above door openings up to 16 feet wide. The major problems that I see for the average dope (me) is one of code interpretation. This is a Major problem because IRC always wimps out by saying final determinations are left entirely up to the municipal authorities. So if I happen to get an inspector who has no engineering background or who does not understand small building engineering, or is not equipped to make fairly complex calculations, I could be screwed if he decides to not be reasonable or not understand building basics. :banghead:

I just love it when someone is protecting "me" from "me". I thought I had a wife to do that.:yahoo::lolol:
Maddog, I couldn't agree any more with your comments and you are right, you could get an inspector who knows squat and never even built anything him or herself.. You basically quoted the spans correctly and I do understand your dilemma. Good luck and if you need anything from me to help you with, send a personal mailing to me and I will do the best I can for you, I am one inspector who helps and not demands.. Plus 42 years in the construction field. This is a simple barn not a church, I like to use that analogy.. I wish it were that easy here at times.. Jeff
 

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Discussion Starter #18
Maddog, I couldn't agree any more with your comments and you are right, you could get an inspector who knows squat and never even built anything him or herself.. You basically quoted the spans correctly and I do understand your dilemma. Good luck and if you need anything from me to help you with, send a personal mailing to me and I will do the best I can for you, I am one inspector who helps and not demands.. Plus 42 years in the construction field. This is a simple barn not a church, I like to use that analogy.. I wish it were that easy here at times.. Jeff
Overall, I would say that most officials here try to accommodate property owners. And I realize that codes are the minimum allowable standard. Speaking for myself, I think that the IRC codes, which have been adapted by my state, SC. have been a positive move. It has eliminated a lot of outdated & unnecessary local rules & regulation. But having said that I still find that, many municipalities still carry on in tradition with the Old codes & Old way of doing things. What's really interesting is that if you ask why a particular new code is not acceptable, they can't give you an answer based on the science or engineering involved. My feeling is that if you have an objection to something like the design or materials used in a building, you should be able to explain that objection. After all its a structure that all can see. Its not some cloud in the sky. And the other issue is that the IRC in itself can be very confusing for the average lay person to interpret. You would think that documents that need to be referred to & understood by engineers & by lay people as well would be written in such a manner as to be understandable to anyone who has a need.

If I need a pencil & I ask you to "Please pass me the Hand Held Portable communicator device", would you know what I was talking about? Lot easier if I would have just said to you "Please pass me the pencil". But then again I'm not Harvard material.:munch:
 

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Overall, I would say that most officials here try to accommodate property owners. And I realize that codes are the minimum allowable standard. Speaking for myself, I think that the IRC codes, which have been adapted by my state, SC. have been a positive move. It has eliminated a lot of outdated & unnecessary local rules & regulation. But having said that I still find that, many municipalities still carry on in tradition with the Old codes & Old way of doing things. What's really interesting is that if you ask why a particular new code is not acceptable, they can't give you an answer based on the science or engineering involved. My feeling is that if you have an objection to something like the design or materials used in a building, you should be able to explain that objection. After all its a structure that all can see. Its not some cloud in the sky. And the other issue is that the IRC in itself can be very confusing for the average lay person to interpret. You would think that documents that need to be referred to & understood by engineers & by lay people as well would be written in such a manner as to be understandable to anyone who has a need.

If I need a pencil & I ask you to "Please pass me the Hand Held Portable communicator device", would you know what I was talking about? Lot easier if I would have just said to you "Please pass me the pencil". But then again I'm not Harvard material.:munch:
Maddog, you've hit the nail so to speak, right on the head. Codes are up for interpretation and difficult if you do not use them daily plus receive the constant education which is mandated here in Mass to stay certified, I've heard the IRC called the intergalactic code, for good reason!.. We have had good codes in the past that were easy to understand for all. Building officials too have a hard time with some of this stuff.. Go to the IBC which is part of the code just a separate book that starts at chapter one, and try to figure out structural with snow loading, sliding and drifting to get the allowable loads.. I don't know to many people that could do this. If an inspector can not answer a question concerning code, get the answers, if not, that person should not be an inspector, especially basic construction!. As far as your mention of not being Harvard material;; I know a grad that would have no idea what you meant with your penultimate description, great lawyer but no........ Jeff :wink:
 
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