You certainly CAN run the vent THROUGH a soffit. Then the vent terminates outside. So, then the argument is that your humid bathroom exhaust comes out and is sucked back into the attic by the soffit vents built into most roof/attic systems.

Is it OK to vent bathroom fan through soffit?

A bathroom fan can be vented through soffit so that the warm air from the bathroom comes out through it and goes outside. However, It is important to keep in mind it can not be vented into the soffit, as this will lead moisture back into the attic.

How do you vent a bathroom exhaust to soffit?






Quote from Youtube video: The best practice these days is to vent exhaust fans directly to the outside. This can be done through the roof through the wall or even through a soffit.

Is it OK to vent a bathroom exhaust fan into the attic?

Can I Vent A Bathroom Fan Into My Attic? No, you should not vent a bathroom fan directly into an attic. The problem with venting into the attic is that the moisture-rich air may form droplets on the wood sheathing, insulation, rafters, and ceiling joists, leading to mold growth.

Can you vent a bathroom fan out the roof?

The fan exhaust must vent directly to the exterior of the home. Do not put the vent termination in a roof overhang or soffit. Don’t put it on a wall near or under a roof overhang. The moist air that’s belched out by the fan can be sucked right up into the open soffit vents and be drawn into your attic.

Is it better to vent bathroom fan through roof or soffit?

Whether it’s new construction or a remodel, a bathroom vent should always vent through the roof instead of an eave, overhang, or soffit. The point of a bathroom exhaust vent, or any vent really, is to remove hot, moist air from the house.

Can I vent plumbing through soffit?





Plumbing Vent Pipe Code



Vents through walls have to terminate at least 10 feet above the ground or adjacent surface, but cannot be below a vented soffit.

How do you vent a bathroom with no outside access?

Use of a ceiling vent



Installing a ceiling vent is probably the most efficient way to ventilate a bathroom with no outside access. A ceiling vent is a unique machine that allows air to escape from the bathroom. In other words, it’s a machine that, like an open window, allows moisture to escape from your bathroom.

Does a bathroom vent have to be vented outside?

Bathroom fan installation requires outside ventilation. If the fan isn’t accessible through an attic, you’ll need to vent through a sidewall of your house. These types of ducts and vents are typically installed when the house is built. If you don’t have a duct leading to a sidewall vent, call a professional for help.

How long can a bathroom vent duct be?

Generally a 4 inch flex duct can carry a fan exhaust for up to 25 ft. Most codes require that.

Can you use PVC for bathroom exhaust fan?



PVC piping is an excellent material to use for venting your bathroom fan as long as the correct type of pipe is used. PVC creates a better seal than metal, so you won’t experience any problems with leakage as you could with using metal ducting pipes.

Can you vent a bathroom fan through side of house?

Can a Bathroom Fan Vent through a Side Wall? You can vent your bathroom fan through a sidewall of your house. In situations where you don’t have access to the eaves of your house and you don’t want to go through the roof, a sidewall is your best option.

Do I need a separate vent for each bathroom fan?

Bathroom fans can share a common vent. Both fans must be of similar capacity and have back-draft dampers installed. The duct must be over-sized by one inch for every additional fan added to the system.

What is code for bathroom exhaust fan?



The model building codes adopted by most jurisdictions typically require bathroom ventilation to be provided either by an operable window (3 sq. ft. or greater) or by mechanical means – a bathroom vent fan (20 continuous or 50 cfm intermittent, vented to the building exterior.

Can you vent a bathroom fan down and out?

In general, you can try venting a bath vent fan “down” but the combination of down-direction, elbows, and total run length may mean that it’s ineffective. Take a look at the installation manual for your fan brand and model. The manufacturer will give guidance on the total duct length permitted.

How do you vent a bathroom plumbing system?

In new construction, the simplest way to vent a bathroom group is usually to install a single vertical vent pipe behind the bathroom sink. This works as long as all the plumbing fixtures connect to the main drain line in the floor within 6 to 10 lineal feet of the sink drain.

Do plumbing vents have to go through the roof?

It does not have to go through the roof. From the plumbing code (I have the 2003 edition), P3103: It must not be less than 4 feet directly beneath a door, openable window or other air intake of the building or adjacent building.

Can a toilet shower and sink share a vent?



Wet venting is most common in conjunction with toilets and sinks; the drain for the sink is also the vent for the toilet. It can also be used for a variety of other applications but due to the following rules this is the most convenient and common situation to run into.

How far can vent be from shower drain?

The maximum distance from a shower trap arm to a vent is usually 5 feet, though some municipalities may allow up to 8 feet.

Does a plumbing vent pipe have to be vertical?

Plumbing vents need to be straight on the vertical. This is necessary to avoid any vapor locks from occurring. When there is a bend in the vent pipe, moisture accumulates and is trapped.

Can a plumbing vent run horizontal?

2. Can Vent Pipes be Horizontal? There is no problem with running your vent pipes horizontally as long as you remember that there should be a minimum clearance of 6 inches above the spill line.