Hi!
I hope this thread is in the right section of the forum.
I'm trying to improve ventilation for two toilets in the cafe where I work. The toilets are about 25m3 each. In the summer we have a major problem with smell, humid and heat in them. We get very busy on sunny days which makes the problem really bad. At the moment there are domestic axial 100mm extractors in each of the toilets with about 2-3m of duct. There isn't really any proper air supply.
In couple of weeks the toilets will be redecorated so I've been asked to try to design the ventilation system. I'm planning to make a hole and a cowl in the roof. Install a 200mm in line mixed flow fan (1000m3/h) with voltage controller. Then use this fan for both toilets by using a y-piece. I know that this will be more than enough of extraction power but I'm not sure about the supply side.
My question:
Should area of the extractor duct be the same as the area of the gap under the door? Is that how it works?
My thinking is:
Area of the 200mm duct = 314cm2
Are of the gap under the door (if cut 1.5in) 276cm2
So roughly the same
Now the toilets entrances are in the little corridor and there is a single door to the cafe from this corridor.
Area of the gap under the door leading to the cafe (if cut 1.5in) = 334cm2
This is less than double the area of the internal doors to the toilets. I don't want to cut any bigger gap cause it wouldn't look too good. I could drill a hole in the wall inside the corridor to let some more air in however in the winter it is better to use the warm air from the cafe as a supply because there is no heating in the toilets.
My question:
Do you think that I should be bothered getting extra supply to the corridor?
What do you think about the design? Is my thinking on the right path?
Thanks for any answers!
I hope this thread is in the right section of the forum.
I'm trying to improve ventilation for two toilets in the cafe where I work. The toilets are about 25m3 each. In the summer we have a major problem with smell, humid and heat in them. We get very busy on sunny days which makes the problem really bad. At the moment there are domestic axial 100mm extractors in each of the toilets with about 2-3m of duct. There isn't really any proper air supply.
In couple of weeks the toilets will be redecorated so I've been asked to try to design the ventilation system. I'm planning to make a hole and a cowl in the roof. Install a 200mm in line mixed flow fan (1000m3/h) with voltage controller. Then use this fan for both toilets by using a y-piece. I know that this will be more than enough of extraction power but I'm not sure about the supply side.
My question:
Should area of the extractor duct be the same as the area of the gap under the door? Is that how it works?
My thinking is:
Area of the 200mm duct = 314cm2
Are of the gap under the door (if cut 1.5in) 276cm2
So roughly the same
Now the toilets entrances are in the little corridor and there is a single door to the cafe from this corridor.
Area of the gap under the door leading to the cafe (if cut 1.5in) = 334cm2
This is less than double the area of the internal doors to the toilets. I don't want to cut any bigger gap cause it wouldn't look too good. I could drill a hole in the wall inside the corridor to let some more air in however in the winter it is better to use the warm air from the cafe as a supply because there is no heating in the toilets.
My question:
Do you think that I should be bothered getting extra supply to the corridor?
What do you think about the design? Is my thinking on the right path?
Thanks for any answers!
