Purlins Steel Or Aluminum

[painterscabin]

Hello everyone, I'm building a house here in thailand, and I'm seeking some imput weather to use steel or the aluminum screw on type purlins.All other parts are steel, rafters and such. The aluminum is very appealing, saves painting, all the wields , and the repainting of all those wields, but unsure about the long term strength of the screws, or the strength of the aluminum in general.

[Spoonman]

First of all can you actually purchase alloy purlins in Thailand ?

Secondly having alloy purlins with "All other parts are steel, rafters and such" there is a chance of galvanic corrosion at the joints if they are no adequately sealed from each other.

I would stick to steel purlins.

[painterscabin]

First of all can you actually purchase alloy purlins in Thailand ?

Secondly having alloy purlins with "All other parts are steel, rafters and such" there is a chance of galvanic corrosion at the joints if they are no adequately sealed from each other.

I would stick to steel purlins.

I'm fairly sure this stuff is aluminum, it might be galvanized steel though, I'll make sure. The locals call it zelie, phonetic spelling. You see this stuff at home pro, global house, and in most of the Cpac type adds. Thanks spoonman, get back to me

[Kwasaki]

First of all can you actually purchase alloy purlins in Thailand ?

Secondly having alloy purlins with "All other parts are steel, rafters and such" there is a chance of galvanic corrosion at the joints if they are no adequately sealed from each other.

I would stick to steel purlins.

+1 Absolutely,

I don't understand why you are considering aluminum, apart from extra cost of using ali fixings and isolating brackets from any steel contact, and in a roof what of the comparisons of expansion and contraction in a climate like Thailand.

There is too many downsides.

If your worried about welds just drill and bolt the steel the welding is usually crap anyhow.

Edited October 10, 2011 by Kwasaki

[splitlid]

they are made from galvanised steel, so perfectly ok.

[Kwasaki]

they are made from galvanised steel, so perfectly ok.

Are they rolled galv steel. ??

What accessories come with them. ??

[splitlid]

yes cold rolled, can get self tappers which make them easy as to fix.

cpac make good ones which are slightly thicker and stronger than the cheaper ones.

[painterscabin]

yes cold rolled, can get self tappers which make them easy as to fix.

cpac make good ones which are slightly thicker and stronger than the cheaper ones.

O.K sounds like some of you know the product, that's great. So the question is steel vs galvanized steel, the screw on type. I'm using cpac tiles, and around here steel welded is the prefered choice, but the screw on galvanized is showing up. So still looking for some imput , have any of you had experience with the screw on galvi steel.

[Litlos]

Have used the steel ones in Oz and no problems, no splinters and the termites hate them.

Just a suggestion if you are going to use self drilling screws get yourself a proper driver and not fall for the idea of using a drill. Did this on my house and ended up with a good case of elbow problems, the proper drivers have a better type slipping clutch to minimise the jar as the screw goes home and the drill locks.

Cheers

[Kwasaki]

but the screw on galvanized is showing up.

Don't weld galv purlins , screw them.

get yourself a proper driver.

Yep !! it's called a screw gun or a tek gun etc etc torque adjustment type of drill for driving self drilling screws into light steel and heavy steel so you do not cause over tightening and put stress on the fixing.

Edited October 10, 2011 by Kwasaki