Draw exhaust duct through plastered outer wall?

[Tomten55]

I am planning to make a hole for a ventilation duct in an exterior wall with plaster, as a company is renovating the facade. I have a decent understanding of 30mm fire insulation, chimney sweep approval, etc. How does the following sound:

A. Kitchen fan with a 150mm connection.
B. Cold draft damper in the fan.
C. Transition 150-160mm.
D. Possibly a fire damper (to check with chimney sweep regarding plaster).
E. 160 mm Spiro with 30mm fire insulation.
F. Exterior wall cap with louver and insect and small animal net (like this: https://www.bauhaus.se/ventilatorka...m98p5W7O53a1oqOgcsGhwg7XH-DN4KbxoCExAQAvD_BwE)



However, I have a few concerns.

- The cap has a 150mm connection, the same as the kitchen fan. It feels strange to use two transitions to Spiro at 160. What are the alternatives? What complicates things a bit is that I don't yet have the kitchen fan since the kitchen renovation is still some time away. The reason I want to do this now is solely because the facade is being renovated anyway, so that the wall/plaster penetration is done properly.

- I'm also wondering how the connection in the plaster should look. Does a sheet metal worker need to install some form of sheet metal with a plaster edge and drip edge behind the cap? The masons suggest they can plaster up to the edges of the cap and it won't be wrong (old house). However, logic suggests that there should be some form of protective plate behind to prevent moisture from finding its way in, as well as prevent drip marks and the like. Maybe something like this?

What do you think?

 

[torbjorn2000]

Hi, how did it go with this?

I have a plastered facade myself and want to run an exhaust duct through it. However, it has been done in the wrong order, as we've just replastered the whole house and are only now realizing that we need to run the exhaust duct there

What I've read is that a plate around it, like in the picture, is not required, just a pipe out to a grille. What I can't understand, though, is that the pipe needs to be fireproof insulated (30 mm mineral wool), but should that insulation then go all the way out to the grille, i.e., through the facade?

And as mentioned, how do you seal it?

 

[yonipacheko]

Hello, how did it go with this?

I myself have a plastered facade I want to run a vent through. However, things got out of order as we've just replastered the whole house and only now realize that we need to run the vent there

What I've read is that a metal sheet like in the picture is not required, just a pipe out to a grille. What I can't understand though is that the pipe should be fireproof insulated (30 mm stone wool), but should that insulation go all the way out to the grille, i.e., through the facade?

And as said, how do you seal it?

Hey! Curious here, how far have you gotten with this? I'm in the same boat ^__^)

 

[Tomten55]

Hello! Curious here, how far have you gotten with this? I'm in the same boat ^__^)

Sorry! Completely missed it. What we did is that we made a pilot hole/guidance hole where the kitchen fan will connect when we eventually redo the kitchen and move the stove. To simplify things a bit for the future, the sheet metal worker and the mason thought this was the best solution. It will involve having the sheet metal worker make a small hood that will then be placed in the metal. So, a metal piece of about 400x400 with a plaster edge and drip edge is what we have for now.