ᐅ Exhaust hood / Roof or wall-mounted

Hello everyone,

We are still in the shell construction phase, but the question about the ventilation system for a desired island range hood has come up.

Should we vent the range hood through the roof or through an exterior wall?
What do you think? Opinions and experiences are welcome.

The most important question in general:
Is venting through the roof with a duct length of about 7 meters (23 feet) even feasible or practical?

A few more considerations:
Exterior wall:
Pros
- shorter duct length, about 2–3 meters (6.5–10 feet)
Cons
- dirt on the exterior wall from dripping grease!?
- west side, wind may blow the fumes back inside
- possible thermal bridge due to the wall penetration

Roof:
Pros
- weather conditions don’t matter
- external motor in the attic reduces noise
- no thermal bridge!?
Cons
- about 7 meters (23 feet) duct length
- high costs

Here are some key details that might be relevant:
- No controlled mechanical ventilation system
- Open kitchen to the living room
- Fireplace planned in the living room
- Chimney draws air from above
- We are not in favor of recirculating hoods

Be sure to talk to the local district chimney sweep.

It’s no use if they don’t approve the installation afterward.

In my case, with a stove in the living room, they insisted on having a rocker switch in the kitchen (also an open living/dining area).

Then you have to consider whether it’s worth blowing the expensive heated air outside, causing cold air to come in through the window.

Sure, the old saying goes, “Air that’s outside can’t cause indoor odors,” but nowadays there are also good options for recirculation systems.

PeterLustig49 schrieb:

- We are not in favor of a recirculation hood

Why not? Do you have personal experience or is it just hearsay?

We have a Siemens extractor hood attached to a Berbel wall box that vents through the wall to the outside. No grease drips onto the exterior wall. Of course, the internal parts of the extractor hood need to go into the dishwasher every 3 to 4 weeks. That’s all there is to it. When not in use, the wall box closes completely tight.

We are very satisfied with this setup.

Sylvia

ypg schrieb:
Why not? Have you had any experience or is it just hearsay?

We currently have one in the apartment kitchen.
It doesn't work... Hence the bad experience/opinion.

The new models offer more power along with safety features.

But since we have an open kitchen, we just want to be safe.

Computersylvia schrieb:
We have a Siemens range hood connected to a Berbel wall vent box that leads through the wall to the outside.
No grease drips onto the exterior wall at all. Sure, the inner parts of the exhaust hood need to go in the dishwasher every 3 to 4 weeks. But that’s about it.
When not in use, the wall vent box closes completely tight.

We are very satisfied with this setup.

Sylvia

How long is the exhaust duct run in your setup?

I’m also concerned that because of the window contact switch on the kitchen window, which forces the window to be open when the hood operates, the polluted air might just be drawn back inside through the open window.
What distance should there be between the wall outlet and the window to avoid this?

So many questions...