thermally broken or not - lintels

[LSB]

I'm just ordering my lintels, catnic, but which is better 

 

These

 

or these
 

 

 

Our cavity is full filled 150 block / block.

What I'm wondering with the 2nd one is about the strength and the 'water'

 

I can see on the first one that any moisture will hit the lintel shell and exit stage right

But, with the 2nd one where will it go and does it then require DPM above.

I can see how the 2nd one will be more thermally efficient.

 

TIA

 

 

 

[Dave Jones]

there has to be a tray installed above lintels so water isnt an issue. 

 

You dont want to build in cold bridging where you dont have to, so the thermally broken is far superior.

[MortarThePoint]

I went thermally broken because, if I recall correctly, it makes as big a difference as upgrading from double to triple glazing but significantly less extra cost. I went with Keystone which need cavity trays either way. I believe some Catnic lintels don't need cavity trays. Also, I heard windows under eaves often don't get fitted with cavity trays. I have cavity trays all round.

 

It's also worth remembering how much harder the inner leaf part works than the outer. The outer leaf may only be carrying a small triangle of bricks whereas the inner leaf could have to support floor loads or roof loads.