Missing Lintel - acrow prop

[CuriousI]

I've just removed the boxing around an existing opening into my 1969 extension on a terrace house. Low and behold there appears to be a timber lintel supporting the inner coursework but nothing supporting the outer course.

The opening originally provide a back door and small window alongside it into the garden.

Do I need to prop the outer course before I start taking down the rear extension? How do I do this if so? Acrow prop underneath each unsupported brick? Or a timber running the span of the opening with acrow props 1/3rd the way across. The opening is around 1.4m wide and none of the blockwork appears lose at present and is probably held in place by the morter and external render.

 

[CuriousI]

Please note the wall is from a 1930s house, so no cavity. two skins of flanin blockwork

 

[pinenot]

"two skins of flanin blockwork" never heard of this, copy and pasted into Google, but nothing. Anyway, you say the build is non cavity blockwork, circa 1930's, presumably they tied both skins together back then just as today! so perhaps the outer skin is supported via the inner one? ...pinenot