Looking for web site with definitions of shed components

[FlyingDuck]

Does anybody know of a good web site where they have a plan of a shed, and name each of the major components in the structure. I have been getting shed quotes, but would love to know what exactly are all these terms they use - mullion, purlin, girt etc etc

[silentC]

A mullion is a divider between two panels. Purlins are the members that run parallel to the ridge over the rafters and the roof sheets are screwed to them. Girts are the same as purlins except they are what holds the wall sheets on.

Anything else? :D

[FlyingDuck]

Thanks for that. What is the difference between a mullion and a portal frame, as they seem to spec the sizes differently, with mullions usually being smaller. Are mullions the "posts" located only at the corners, and portal frames all the other posts/rafters combinations inbetween?

I wish I could find a web site with a schematic naming all these parts.

[Barry_White]

Flying Duck have a look at this pic it may help you.

[Barry_White]

Barry, the attachment doesn't come up, it says it is invalid.

Try now. I had deleted because I was trying to enlarge it as it is a bit hard trying to read the components.

[Groggy]

Try now. I had deleted because I was trying to enlarge it as it is a bit hard trying to read the components.Works fine, post gone. We're both a bit quick huh!

[silentC]

Are mullions the "posts" located only at the corners, and portal frames all the other posts/rafters combinations inbetween?
Mullions can occur anywhere. In the context of a shed, they are the vertical members that give you somewhere to fix the girts when there is an opening like a door. There is usually a special purlin called a facsia purlin which runs along at the edge of the roof line. The mullions usually connect to this at the top and are dynabolted to the slab at the bottom. Then you fix you girts to it.

Portal frames are the main vertical columns and connected rafters. You make them up on the ground as a unit and then stand them up. They are the main structural component of the shed and define the 'bays'. You have one more portal frame than you have bays. SO a 4 bay shed has 5 portal frames.

[Barry_White]

Mullions can occur anywhere. In the context of a shed, they are the vertical members that give you somewhere to fix the girts when there is an opening like a door. There is usually a special purlin called a facsia purlin which runs along at the edge of the roof line. The mullions usually connect to this at the top and are dynabolted to the slab at the bottom. Then you fix you girts to it.

Portal frames are the main vertical columns and connected rafters. You make them up on the ground as a unit and then stand them up. They are the main structural component of the shed and define the 'bays'. You have one more portal frame than you have bays. SO a 4 bay shed has 5 portal frames.

Well said Silent. You said it with words whereas I had to use a picture. Flying Duck should be able to work it out now.

[boban]

A couple of weeks ago, just up the road from my place, I saw them erect a shed by using two cranes. They did the whole roof on the ground then lifted it into place. Then they put the walls in underneath.

It was quite a sight and pretty clever I thought.

[journeyman Mick]

A couple of weeks ago, just up the road from my place, I saw them erect a shed by using two cranes. They did the whole roof on the ground then lifted it into place. Then they put the walls in underneath.

It was quite a sight and pretty clever I thought.

Saw something similar a few weeks ago, huge roof over an outdoor sporting area (bowls?) , unfortunately it collapsed partway through. I drove past after it had collapsed, portal frames had split down the middle and the roof was half down with some elevating work platforms stuck under it. Hopefully no one was hurt. Unfortunately I didn't have my camera with me. :(

Mick

[boban]

I would assume that you would want some temporary (or even permanent) chords to stop the splitting.

Someone must have done something wrong or maybe mother nature had something to to with it up there on that job.

Must admit, it looks pretty scary. Im not sure that I would want to be getting underneath even with 2 25tonne cranes holding the roof.

Im guessing you would have heard about it if someone got seriously hurt. Like you said, hope no-one was unlucky enough to get in the way.

[FlyingDuck]

Thanks for the replies. It all makes sense now.

[bitingmidge]

Now that the question's been answered, it's fairly common to build large roofs on the ground then lift them.

"Fairly common" in so far as roofs that large are not particularly on every street corner I suppose.

http://www.dormanlongtechnology.com/English/roof_jacking.htm

Cheers,

P