Air brick duct - Airbrick to raised patio issue

[Seb]

Can anyone please advise -
we are laying a patio level with the new extension interior floor in front of bifolding doors. There are currently air bricks
75mm below the door threshold how can we lay the patio level to the interior without blocking the airbricks - does it need to be ducted to a vent in the patio ?or can you simply leave a gap in the mortar under the patio? :;):

[dig dug dan]

where is the dpm? the finshed patio needs to be 150mm below it.

[lutonlagerlout]

you need telescopic vents then either go under the patio via a suitable pipe or have the vents above,which would involve cutting out brickwork and re instating

we did this yesterday to maintain the airflow through a step

LLL

[GB_Groundworks]

The last time we did a flush threshold we knocked two air bricks out and used 110 pipe instead and ran that to the dwarf wall of the patio then installed air bricks there. We tanked and membraned the wall under the door and installed shallow linear drains to the threshold.

We also installed an additional 2 new air bricks outside of the patio