Ventilation in the bathroom and toilet: principle of operation, typical schemes and installation features

Alexey Dedyulin
Checked by a specialist: Alexey Dedyulin
Author: Grigory Skok
Last update: March 2019

A bathroom and a toilet are rooms, in the process of arranging which, first of all, you need to think about organizing intensive air exchange. This is due to the specifics of the operation of hygiene facilities. Contaminated and waterlogged air should be unobstructed, and a fresh portion should be replaced.

We will tell you how ventilation should be arranged in the bathroom and toilet according to building codes and rules. In the article we presented, the options for organizing ventilation, tested in practice, are examined in detail. Independent home masters with us will find detailed installation manuals.

What is ventilation for?

The opinion that the lack of a ventilation shaft in the bathroom and toilet will only lead to fogging of the mirrors is fundamentally wrong. The main problem is the appearance of a fungus (most often it can be seen on the seams between the tiles) and rust on the surface of appliances and furniture.

Often, it is because of the incorrectly designed ventilation system that corrosion affects the working parts of the washing machine, which is the reason for its breakdown. This does not end the list of problems that the lack of intensive air exchange leads to. As a result, poor ventilation will have a detrimental effect on the health of residents.

Sanitary requirements and standards

There are special standards that you must adhere to when organizing forced air exchange in rooms with high rates of humidity. At a minimum, a supply of fresh air of 6-7 m should be ensured.3/ hour for every cubic meter of the bathroom and about 8-10 m3/ hour - for a toilet or a combined bathroom.

Bathroom ventilation
Experts recommend organizing ventilation, whose performance is 20% more than the required volume in m3/hour

The difference between natural ventilation and forced ventilation

There is natural and forced ventilation. In the first case, air exchange is ensured by the circulation of air masses through door and window openings. About a century ago, natural ventilation was considered the most effective way.

Today, it is unable to provide a sufficient level of air exchange, therefore it is used only for inflow. To fully ventilate the room, choose the option with coercion. After all, no one wants to open a window in the winter for a long time and let out heat.

The organization of forced ventilation involves the installation of an exhaust fan. Thanks to this, you can save precious heat, remove excess moisture and fill the room with fresh and clean air in a matter of minutes.

Forced ventilation circuit
The main reason why you should install forced ventilation is precisely sized doorways and the tightness of modern double-glazed windows. Such perfectionism, while retaining heat, makes any natural air exchange impossible.

Optimal Performance Calculation

Before going to the store and buying equipment for installing forced ventilation in the toilet and bathroom, some calculations need to be done. To choose the optimal equipment for productivity, you need to know the exact volume and type of room.

Each room has its own air exchange rate. This characteristic shows how many times the air in the room should be completely refreshed per unit of time (usually one hour is taken). Since the bathroom and toilet are considered one of the wettest places in any apartment or house, a maximum value of the air exchange ratio of 10 is recommended.

To calculate optimal performance exhaust system, it is necessary to calculate the volume of the room. To do this, multiply the area of ​​the room by the height of the ceilings.

Further, the obtained value is multiplied by the rate of air exchange. The result of the calculation is the minimum exhaust system power for the bathroom and toilet (m3/hour).

Fan housing
If the fan cannot be placed in the optimal place for the organization of intensive air exchange, then its power must be multiplied by 2-3 times

Also, openings for air flow should be provided immediately. To do this, you can leave a gap of up to 2 cm between the floor and the door, install special grilles at the bottom of the doors to the bathroom and toilet, or drill holes yourself. But the last option does not look the most attractive way.

Exhaust Fan Classification

When planning the arrangement of the ventilation system, special attention should be paid to the principle of its operation and its individual components. After all, performance, noise level of equipment, installation cost and durability depend on this.

For the forced evacuation of exhaust air from the room, three types of fans are used:

  • diametrical;
  • axial;
  • radial.

The first variety of devices is designed to work in heat guns and air conditioning systems. Therefore, it is not suitable for organizing ventilation in the bathroom and toilet. It remains to choose from two other types.

The main difference between axial and radial models is their low cost and high power. But at the same time, the device will make a lot of noise. The axial fan is an impeller to which the blades are attached. The system is driven by an electric motor.

As for radial units, their functioning is based on the action of centrifugal force. Thanks to the rotation of the impeller, the air masses are moved together with the blades.

At the same time, the slope of the blades can be changed, due to which the amount of energy consumed by the device decreases and the level of noise emitted by it decreases. With popular models silent fansintended for installation in bathrooms will be introduced by the article recommended by us.

Ventilation check valve
To prevent air from the ventilation shaft returning to the room, it is recommended to buy devices with a non-return valve. Such devices are indispensable in modern apartments.

Basic equipment selection criteria

Manufacturers offer just a huge assortment fans for exhaust systems. Therefore, it is not surprising that every unprepared buyer falls into a stupor and does not even suspect that he is better to order.

When buying an exhaust device for a bathroom and toilet, you need to pay attention to the following points:

  1. Duct diameter. Depending on this characteristic, the fan nozzle is selected. Typically, standard models have diameters of 150, 125, or 100 mm.
  2. The presence / absence of ducts, as well as their location in the room. These criteria affect where the fan will be installed.
  3. Power. The characteristic is important when choosing so that in the future the exhaust equipment can cope with the functions assigned to it.
  4. Moisture proof. This indicator is marked in Latin letters IP. The minimum required value for a plumbing unit is IP30, but it is better to spend some money and order a device with IP44. In the latter case, it will be located in a special tight casing, protected from moisture and splashes.
  5. Noise level. Few people pay due attention to this important characteristic, but in vain. After all, a silent exhaust system will make being in the bathroom and toilet more comfortable.

Given these subtleties, you can choose a model that will be inexpensive and will satisfy all your wishes.

Fan after unpacking
Typically, the complete set of the fan includes the device itself and four dowels, which are needed for its installation. In most cases, a cardboard box is used to pack the device.

Additional equipment features

An excellent solution would be to order a fan with additional features. Most often, customers prefer models with a built-in timer.

In this case, the user can leave the factory settings or program the operation of the device by himself, changing the operating time, delay of switching on, etc. Thanks to this, you can automate the process of ventilation of the toilet and the bathroom.

Devices with a built-in timer are quite expensive. Therefore, their choice should be treated with full responsibility. The best products from Maico have proven their worth. This manufacturer offers a number of models that are equipped not only with a timer, but also with other additional functions.

The fans will help save energy, allowing you to switch the base load. That is, the unit can operate in two modes: half its power and full, when you need to update the air in the room in the shortest time. Thanks to this function, the noise of the ventilation system is significantly reduced and energy is saved.

Backlit fan
A good solution would be to buy a device with a clock or backlight. Such additional functions will make taking a shower or bath more convenient and comfortable.

Any specialist will prefer a device with a built-in humidity sensor. Its feature is that it turns on only by the signal of the built-in hygrometer. Thanks to this function, energy is saved and there is no need to output a separate electric point for the fan or to connect the device to the light switch.

System components and materials

Today, ventilation is collected from ductwork round or rectangular section. As a rule, they are made of metal or plastic.These elements are mounted behind a suspended ceiling.

If we are talking about bathrooms and toilets in a small apartment, then in such housing the ventilation duct is a hole in the wall where the fan is inserted. In this case, there is no sense or need to design a complex, ramified system.

As for private houses, for them ventilation is constructed from the following elements:

  • Ductwork. It is much more convenient to install rectangular ducts. They are compactly placed under the ceiling and do not take up extra space. These are pipes, the length of which can be 2, 1 and 0.5 m.
  • Fan. An invoice or a built-in device is used. The latter variety is best used in branched and complex systems. Overhead models are recommended for ventilation of one room.
  • Swivel knee. In the case of rectangular pipes, the swivel elbows can be vertical and horizontal.
  • Couplings. These elements are used to connect direct sections of the ventilation system.
  • Check valves. They are designed to prevent air and insects from entering the mine.

Mounting will also be required during the installation process. It is much more convenient to use ready-made elements. They will greatly simplify the installation process and speed up the work.

Bathroom ventilation scheme
But if you need to save money, then the fastening elements can be made independently

In the event of an error in the design or insufficiently effective operation of the ventilation system in the bathroom and toilet of a private house, the problem can be fixed by installing exhaust vent valve into the wall. Features of the choice of the specified device and installation rules are given in the article, the contents of which we advise you to read.

Installation of ventilation in the bathroom and toilet

Before starting installation work, it is necessary to carry out preparatory work. First of all, you need to compare the diameter of the exhaust device with the size of the shaft.

If the ventilation hole turned out to be large, then a plastic pipe or corrugation is inserted into it. In this case, the voids should be repaired with mounting foam. If the entrance to the ventilation shaft is smaller, then it can be expanded using a hammer drill.

Determining the installation location

For forced ventilation to be as effective as possible, it is not enough just to purchase powerful equipment. It is equally important to choose the right place for installation.

As extractor hood in the bathroom designed to remove hot humid air, the best solution would be to install it in the upper part of the wall, which is located opposite the door.

An important is the organization of the inflow into the room - you have to build a special grille in the lower part of the door or leave the usual slot under the door (a more economical way). Such options will allow fresh air to flow from the living room to the bathroom.

Diagnostics of the condition of the ventilation duct

If you are thinking of remodeling a bathroom or toilet, then before starting any work, you should carry out diagnostics of ventilation ducts ways available to the owners.

First of all, the draft is checked, for which a sheet of plain paper, a lit match or a lighter is leaning against the shaft. If the paper sticks to the ventilation grill, and the flame tilts toward the channel, then this is a good sign.

Air shaft
To improve traction, it is recommended that you check if the ventilation duct is cluttered with debris left after inept repair work or for any other reason. After cleaning, check the draft with the door open and closed.

Choice of device connection diagram

If we consider a standard apartment in a new building, then in the vast majority of cases, natural ventilation is not enough to remove all excess moisture from the bathroom. The one exception is a private house with a window in the toilet.

But when arranging forced ventilation, the question is: how long should the exhaust device work? Often apartment owners connect the fan to the light switch. This means that the device will be able to work exactly as long as the person will be in the bathroom. This may not be enough.

The second method is based on connecting the fan to a separate switch. But in this case, the user will forget to turn on / off the device. Therefore, a suitable solution would be to install a fan with a humidity sensor. Such devices work autonomously and, without human intervention, remove excess moisture from the bathroom.

Connection diagram of the fan to the switch
Due to the convenience and energy saving, the method is most in demand when the fan is connected to the light switch. But this method is not very efficient.

Subtleties of installation of the fan

Before proceeding with the arrangement of the ventilation system, it is imperative to familiarize yourself with the instructions that come with the devices. In the vast majority of cases, the insert describes in detail the entire installation process. This will greatly simplify and speed up the work.

The most time-consuming step is installing and connecting a fan.

If there are no manufacturer's recommendations or there is no translation into the native language, then you should perform the actions in the following sequence:

  1. Remove the front cover.
  2. On those areas where the fan adjoins the wall, it is necessary to apply polymer glue, silicone or liquid nails. All of these mounting methods are perfect, since the exhaust devices are most often made of plastic and, therefore, have a small weight. Therefore, liquid nails will be enough.
  3. Insert the fan so that its working part (electric motor and wheel with blades) are completely “recessed” in the wall.
  4. Press the unit body firmly so that the adhesive can grip.
  5. Install a mosquito net. This element will protect from the penetration of various insects and debris from the ventilation duct into the room.
  6. Fasten the front cover using the screws or dowels that come with the kit.

The final stage is laying the cable and connecting the ventilation system to the electrical network.

Installation of ventilation in the bathroom and toilet
The whole installation process is quite simple, but if you have any problems or difficulties, it is better to entrust this work to professionals

Forced ventilation significantly increases the amount of air discharged from the room. But since the front cover overlaps a considerable part of the channel when the device is turned off, the flow rate decreases several times. Because of this, its performance drops significantly.

The above problem is solved by installing an air intake grille. This will help restore normal performance. The second way is to leave a small gap (1-3 cm) between the front cover and the wall. Air will be sucked into the resulting gap and the ventilation will work in normal mode.

Connect the fan to the network
When connecting the ventilation system to the electrical network, it is necessary to adhere to safety rules. First of all, you need to make sure that the wires are de-energized. In addition, it is better to use not “twists”, but terminal blocks to connect them.

Common installation errors

If an inexperienced master is engaged in arranging the ventilation system, then often there are situations when, after finishing work, its performance does not satisfy the wishes of the tenants or it does not differ in efficiency.

The reason for this is to make installation errors. To avoid the appearance of elementary problems, it is necessary to know some nuances.

Most often there are such errors when installing a ventilation system:

  • the channel is not designed correctly, which greatly complicates the movement of air;
  • fans are very noisy during operation;
  • the tightness of the mine connection is broken;
  • the ventilation system passes through the living room and its noise interferes with the normal life of the family.

If the design was not performed correctly, then the above problems will certainly appear. In this case, often to correct them you need to completely redo the ventilation system.

Appearance of ventilation for the bathroom
In some cases, a strong hum during the operation of the fan is a clear sign of its improper installation and the error, which is called “alignment”. This problem is solved by dismantling the device and reinstalling it, but with the exact observance of technology

You can go the easy way. For example, it is recommended to use noise absorbers to reduce noise. With regard to improving ventilation performance, for this you will have to install a new, more powerful exhaust device and check the quality of the arrangement of the air flow into the bathroom and toilet.

Recommendations from experienced professionals

For people who are first faced with the organization of ventilation in the bathroom and toilet, it will be useful to familiarize themselves with the advice from experienced craftsmen. First of all, they recommend ensuring a normal flow of fresh air into the room. Indeed, otherwise the operation of the exhaust fan will be meaningless.

It is not necessary to buy expensive and overall systems. Spending fabulous sums is not always the optimal solution. It is enough to correctly and competently select the devices, then even cheap models will perfectly cope with the ventilation of the room.

Bathroom ventilation
Choosing a fan, in no case can not save on quality. After all, the health of each family member, as well as the life of the device, depends on this. It’s better to spend money once, but order a device that will serve for decades for good

If the house has air conditioning, an ionizer, a cleaner, household humidifier and similar devices, it is still necessary to engage in the installation of ventilation. After all, none of the devices listed above does not provide an influx of fresh air into residential premises.

Rules for the operation of the exhaust system

In order for the equipment to serve as long as possible, regular maintenance work is necessary. Indeed, dust and dirt accumulate on the fan blades over time. This does not allow the device to work at the maximum of its capabilities and provide decent air exchange. Moreover, if timely cleaning is not carried out, the device may fail.

Preventive work includes regular inspection of the ventilation system for clogging and washing the fan blades. This approach will allow even in a modern house, characterized by high tightness, to always breathe fresh and clean air.

Conclusions and useful video on the topic

Video # 1: Secrets of installing a hood in the bathroom and toilet:

Video # 2: Creating separate ventilation in the bathroom and toilet:

The installation of a forced ventilation system allows solving the problem of airing the premises, which is relevant for modern houses and apartments. In bathrooms and toilets, a window is rarely installed, so the only right and reasonable solution is to provide intensive air exchange artificially, by installing a fan in the system.

Do you want to share your personal experience in arranging ventilation in an adjacent bathroom or a separate bathroom? Do you have interesting information that will be useful to site visitors? Please write comments, ask questions, post photos on the topic in the block below.

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Visitors Comments
  1. Alexander

    In general, ventilation plays an important role in the bathroom, so we approached this matter responsibly. We live in a private house, it was not very desirable to put a window. Experienced craftsmen were called for this. The hood was forced, when the light is turned on, it starts to work too. In the bathroom, moisture is almost not felt now, we do not observe mold, but it took a lot of money.

  2. I didn’t take much steam, did not calculate the size of the room, etc. The characteristics of the fans indicate what area they can cover, and this is quite enough, especially if the bathroom is standard. I bought an axial fan with a timer, it turns on several times a day for 10 minutes. This is enough to keep the air fresh, but the energy is consumed little and the noise of the blades does not interfere.