Patio doors sill detail help

[rh2205]

We are having EWI with render installed, the patio doors are therefore moving right to the front face of the existing brickwork rather than a normal 20-30mm set back from brick work (with the new 100mm insulation providing the setback). The approved window installer is now recommending we basically have a sill with pretty much no overhang as the EWI does not extend below as we are having an internal (but not external) flush threshold pretty much at dpc level (though we’d don’t really have a dpc as old house) so they don’t think there will be anything to rest the aluminium sill onto properly, the builder initially talked about using a steel angle or similar to help support the sill but now no one sounds keen on doing this as they think it will be too flimsy or look really obvious and crap. Could it lead to problems to not have any proper sill overhang and if so how can we get around this so both the builder and window installer are happy with a solution to support the sill on? Worth mentioning the patio doors themselves are big and thus the deadload of the door itself will rest on the brickwork still so this is just a question of how to get the sill itself to be supported properly without having any setback below as the EWI won’t continue underneath.

 

Edited December 20, 2020 by rh2205

[ProDave]

What are you doing outside?

 

You need your paving / decking or at least a step set so the sill rests on that.

[Roundtuit]

Dress the brickwork under the doors with lead to make sure any run-off from a small sill is directed below dpc?

[Temp]

How deep are the foundations? Trench foundations are typically wider than external walls so you could dig down and build a single brick/block "wall" up to support the patio door sill.