steel web truss building truss spacing ?

[mikewatson]

I am going to be puting up a 42x60 worldwide building that i all ready have . the truss spaceing is 12 on center , i would like to space at 14 or even 16 ft if i could making the building longer 70 or 84 ft . this would allow more room and to be able to put bigger than 10ft wide doors on the side . This is a hybrd system with wood purlin and grits . If i could streach it out instead of 2x8 purlin and 2.4 girts use 2x10 purlins and 2x6 wall grits for more strength to hold the load ? thoughts on this idea or im being just stupid ?

 

[rburke65]

Well.....we havent any pictures, we don't know what the trusses were designed to span, we don't know where you reside, we don't know roof loads, snow loads, wind restrictions, we dont if you plan on storing any thing up in your ceiling/attic, we don't know about a possible ceiling,we don't know......is that enough? Oh,ya, 'Welcome to Garage Journal, from Ohio!'.

 

[rancherbill]

The trusses were designed for 12' spacing. There are are number of factors, some of which are snow loading, weight of roofing material, bla bla bla bla.

It is not a good idea to try to do something they were not designed for.

 

[mikewatson]

in wisconsin . this building has not put up yet . trusses were designed for 12on center .building was was desiged for snow load rating is 40 and wind is 20 . it is a open web steel truss there is no storage on top. built just like this http://www.worldwidesteelbuildings.com/steel-buildings/worldwide-difference.php

 

[theoldwizard1]

It is not a good idea to try to do something they were not designed for.

And will violate building code simply by being "not built according to plans".

Do it right (get the plans revised which may mean new trusses) or you will ave to do it over. Worse, if there is a structural failure you will be 100% personally liable ! Your insurance company will simply walk away.

 

[mikewatson]

i have be trying to get the them to build and send me two more truss sections to make it the 24ft longer but so far no luck .

 

[kbs2244]

The web site mentions 10 and 12 foot spacing.
Nothing more.

 

[rancherbill]

i have be trying to get the them to build and send me two more truss sections to make it the 24ft longer but so far no luck .

Get a quote for a 12x42 building.

To start, you bought it from somebody and get the specs / engineering data and see if it's suitable for your area. You mentioned wind load of 20 mph. That is wrong.

It would really help if you played the game and put your location in your profile so people could make decent suggestions.

Right now, I would say you have a very nice hay shed. To put things of higher value you'll want insurance, which requires inspections, which require paperwork.

I'm not being rude just blunt.

 

[Bib Overalls]

I also have a hybrid metal truss building with wood girts. My plans specified 10' spacing and an additional 2"x6" post in the center of each bay. This post keeps the girts parallel and, because it is anchored at the bottom, it keeps the wall from creeping outward from the slab.

When I remodeled the building I replaced the wood 2"x6" posts with 1.5" square metal tubing.

I would not deviate from the specifications provided by the manufacturer.

 

[Ross/Kzoo]

For almost 40 years I did design work dealing with safety factors. They are there for a reason.They may not be fully stressed today, tomorrow or next year but they may be. Accidents are usually a combination of things going wrong . The same applies to building failures.

 

[gazza]

I agree with others, there are lots of details you need to know.
About 11 years ago I designed and built a 40' x 60" x 14' high steel shed, with 3 by 20' bays. Both purlins and girts are 6" to span the 20'. But, and there is always a but! after I designed what I wanted to build I gave my plans to an engineer to do the computations. Initially he said it couldnt be done with the 20' spans but said it could be made if he redesigned a few features.
So I ended up with my 20' spans but the purlins and girts were all a thicker guage steel and on all of the joins there was a 3' overlap from one purlin to the next on both the purlins and girts. Also to increase the rigidity of the whole structure he added diagonal bracing in both the walls and roof in every bay. It seemed like a lot of work at the time but I would guess it only added about another $1000 to to the overall cost and I still was able to build exactly what I wanted.
So as an option you could pay somone to tell you exactly what you need then you know its safe and you have the computations to prove it.