Thread: Lintel Sizes

thanks. nice idea. i'm going to assume that it will be loadbearing just in case the trusses do end up sitting on the wall - i know it wont but i'm paranoid now!

i'm starting to lean towards the new wall idea !

If the trusses sit on a wall that they where not designed to it could cause major structural issues.

well i was told that the trusses have been designed to clear span. but get what you are saying.

diagram???

which tool is best to use. reciprocating saw or is the power saw ?

A power saw would get the cuts more square, but you'd have to remove the top plate and all the nails first if you value your blade. A recipro with a metal cutting blade would slice through everything with the top plate in place, but they can wander out of square.

Originally Posted by karthioli

diagram???

which tool is best to use. reciprocating saw or is the power saw ?

Thats what could happin to your truss top chord if it sits on a internal wall

Originally Posted by toecutter

Thats what could happin to your truss top chord if it sits on a internal wall

Definately. Unless there is a joint (webs intersecting within 100mm).

Even then it could change the whole dynamic of the roof trusses.

But have they cambered the trusses up? And if it is only clearing the internal wall by 5mm then it must be fixed by dropping down the internal non loadbearing walls. I can't believe that they were that stupid to allow the loadbearing walls to be at the same level.

Ideally, the trusses should sit flat after 6 months of loading, so if they are not cambered either they are lightly loaded and will only deflect 1 or 2mm or the company has made a mistake.

Originally Posted by DvdHntr

I can't believe that they were that stupid to allow the loadbearing walls to be at the same level.

Yeh, from my experience internal wall frames are designed with minimum 20mm clearance, and special brackets are supplied for connection to give the internal walls more lateral stability, whilst still enabling vertical settlement of the truss bottom chord via the slotted nailing points, which are supposed to be nailed at the top of the slots.
It would certainly cause some havoc with your cornices if there was 20mm movement though. What is the recommended time period between roof loading and plastering anyone?

Originally Posted by pawnhead

Yeh, from my experience internal wall frames are designed with minimum 20mm clearance, and special brackets are supplied for connection to give the internal walls more lateral stability, whilst still enabling vertical settlement of the truss bottom chord via the slotted nailing points, which are supposed to be nailed at the top of the slots.
It would certainly cause some havoc with your cornices if there was 20mm movement though. What is the recommended time period between roof loading and plastering anyone?

Special Brackets are called "internal wall brackets. They only support the wall laterally and so the wall doesn't get loaded by the roof.

In most cases, the truss will have less than 5-10mm of movement left after initial loading. Usually the plastering is a week or two after the roof and walls are all up. And even then, the cornice is usually the last thing installed for this reason.