Lintels part 2

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I'm not a buildings expert but since becoming a home owner, but I have enjoyed learning about the construction and history of my house and houses in general.

In an older post I talked about  lintels and cavity trays.
During my ongoing renovation I've been able to obtain deeper access to the structure.

The UPCV windows had plastic trim/architrave internally which when removed allowed a scope to be passed into the cavity.

I was expecting boot lintels but in both places I checked (the front door and toilet window) there are separate concrete lintels for the internal out external skin separated by an air gap. In fact the gap is continuous with the cavity and so should have been filled with insulation.


The lintel above the front door has a taper which would direct water away form the inner wall however due to the current position of the front door that would be inside the house. I believe doors were previously placed further towards the inside of the wall.

The following video was shot looking up into the lintel above the toilet window. There is a bitumen cavity tray and void below. The white wool cavity wall insulation can be seen only on the periphary.



The windows were confirmed to be installed before the cavity wall insulation.
What's interesting is that the lintels would show up as cold spots on thermography and probably assumed to be cold bridging which is not the case here.



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