What is this truss called?

[freddiemercurystwin]

I'm doing a loft (joy!) anyhoo there are two trusses in this loft at present, would you describe this as a King truss or has it got a unique name? Just curious really.

Untitled

• freddiemercurystwin
• 4 Mar 2010
• 1

Untitled

• freddiemercurystwin
• 4 Mar 2010
• 1

Untitled

• freddiemercurystwin
• 4 Mar 2010
• 1

edited for my rubish spolling!

 

[stuart45]

Never seen one quite like that. The Kings post truss supports the purlin from underneath. The Trada truss supports the purlin like that, but it's usually bolted together, an a slightly different design.

 

[freddiemercurystwin]

Never seen one quite like that.

Not just me then!

 

[Scargill]

Cant see any trusses, seems to me just to be and old cut roof with purlings and some struts.

 

[Nickam]

Yep, me too. Just a traditional cut roof with what looks like twin purlins with struts and binders.

 

[noseall]

The 'truss' is what you are seeing in the picture. It is an arrangement of timber elements that collectively serves to support the roof.

Just because it ain't a (fink) truss rafter roof, or that the roof is predominantly a cut roof, does not mean there can not be a truss within the roof.

 

[Ossy]

I concur with the opinion that this isn't actually a truss. If it was there'd be a principal rafter but they all look common to me. Also the 'tie' doesn't even pick up the feet of the rafters, so isn't really doing much. Looks like an attempt to prop some sagging purlins, or, depending on the spacing, some support for a water tank that's no longer there?

 

[freddiemercurystwin]

Looks like an attempt to prop some sagging purlins, or, depending on the spacing, some support for a water tank that's no longer there?

Purlins as straight as the day they were installed and the 'tie' (which obviously isn't tying anything together) as you put it extends into thin air on each end of the two trusses or whatever they're called. I was just interested to see if these beasties had a particular name or are just an ad hoc approach.

 

[Ossy]

It's a strange one to be sure! Are there any load bearing walls beneath (stud or masonry)? It's not a truss, but looks a bit 'remedial' to me, hence the comment about sagging purlins. Looks alot like propped purlins to allow the purlin size to be kept down. I bet, if it was designed, that wasn't quite how the designer envisaged it to end up...

 

[freddiemercurystwin]

There is one masonry wall in the middle of the house beneath the centre of the tie (so it would be vertical on my drawing if I'd drawn that bit! ), the remaining stud walls beneath bear no relationship to the 'trusses' above so whilst the props in the middle are transmitting their load directly into the masonry wall its not clear where the props on each end of the 'ties' are getting their support from.

 

[freddiemercurystwin]

Well, according to my SE, the purlins are holding the rafters up and are are also suspending the ceiling. The masonry wall in the middle is doing nothing especially as it doesn't cross the whole width of the house.

You can all relax and sleep easy in your beds tonight now!