View Full Version : Lets talk c perlin.

04-12-2011, 04:42 PM
How far of a span can you get out of 4",6", and 8" c perlin? 30' to far of a distance between posts for 8"?

bowfishin fool
04-12-2011, 04:43 PM
30' is a long ways, but i'm sure someone on here can give you a detailed analysis...;)b:D

04-12-2011, 04:45 PM
That would be further than I would want to span without any support in th between uprights. It stick to 10 or 15' if it were me.

04-12-2011, 04:46 PM
Mine are 20' with 8" and I would not attempt to go any further. Call a Mueller rep and ask them. They are very helpful.

04-12-2011, 04:46 PM
I am not structural engineer, but the sell it in 20' stick for a reason i bet!! 30 feet is a dang long span with no center support. I beam maybe 8" would work, but C perlin would be a little risky IMO!

04-12-2011, 04:47 PM
Pretty sure Mueller is good up to 24' on 8". Don't think they will engineer any longer than that
I've got 24' bays with them every 5 feet apart

04-12-2011, 04:48 PM
What gauge is the perlin?

Rockpit TX
04-12-2011, 04:50 PM
I built a 25'Wx20'D carport out of 8" material 5 years ago and it is still as solid as the first day, with no sag whatsoever. Dont know about 30':)

04-12-2011, 04:52 PM
24 foot is the max

04-12-2011, 04:58 PM
30' with 8" c purlin will hold but the outside elements may not hold it down. The best way to go is 8" c purlin on a 20' span as it was told to us. He was right about it to.

04-12-2011, 05:52 PM
A 10''x31/2'' 12 gauge may work

04-12-2011, 05:57 PM
Ok thanks, looks like ill be drilling some more holes and adding some more post. The car port is 85' x 30' and I went every 20' wide with a upright. But, I thought I could get away with the 30' deep without having to had a center brace.

04-12-2011, 06:10 PM
I am not structural engineer, but the sell it in 20' stick for a reason i bet!!

"C" purlin is sold in 20,25 or 30 foot lengths!

black dallas
04-12-2011, 07:08 PM
24foot is fine on eight inch c perlin

04-12-2011, 08:25 PM
I cut this from Flexospans website. It may help as there are several factors to consider for the spans on purlins. They have a number if you want to call 800-245-0396.
Notes from the website are: Many different variables can affect loading. For instance; drift loading, building height,geographic location, wind loadings.
The span of the purlin depends on the loading you are placing on it.

04-12-2011, 08:31 PM
If your going to have other purlines welded to the 30' rafters then you really need to use I beam and I'm pretty sure it would be a 12' x 19# beam at that.

8" C will span 25', 6' will span 20'.

04-12-2011, 09:23 PM
I think I did 15' with 8"........that may have been stretching it a bit.


04-12-2011, 09:52 PM
14 GA import Purlin

4" = 12'
6" = 18'
8" = 25'
10" = 30'

Dale Moser
04-12-2011, 09:56 PM
Our building at work has the uprights on 25' centers, with 8" purlin, that would put the span at 24' or so.

04-12-2011, 09:57 PM
tx tech nailed it.