Often, a stylish living room is arranged in the attic of a one-story country house, turning it into a kind of two-story house. Previously, the attic is insulated, waterproofed, a vapor-tight layer is laid.
And the fact that good ventilation of the roof space is required is forgotten, considering it an extra waste of time and money. As a result, in the best case, they receive a room unsuitable for living.
Do I need ventilation under the roof
It is convenient to turn the cold attic of a country house into an additional residential floor. From the attic there is an excellent study, bedroom or art workshop with bizarre geometry of walls and ceilings.
One problem - many customers of such alterations refuse to equip ventilation there, believing that the builders want to deceive and take more money. Some home craftsmen involved in construction without the involvement of professional builders believe that the attic does not require ventilation, because this is an extra part of the cost.
An attic can unexpectedly turn out to be an excellent living space, if it is properly equipped
This decision is justified by the fact that 50-70 years ago no one installed all kinds of aerators, spotlights and other elements that are now massively sold in all construction stores. And at home, despite the lack of ventilation in the attic, they still stand and look better than some modern cottages.
Indeed, many old houses are perfectly preserved, but not due to the lack of ventilation. Everything is just the opposite - the natural ventilation of the attic space is perfectly organized in them.
In such houses, no one has equipped in the attic an additional room for permanent residence. Yes, and materials for insulation were not used here - the attic is cold, has dormer windows, additional gaps and slots for the entry and exit of incoming and outgoing air flows.
It is convenient to turn the attic space into a nursery, especially if there has been a replenishment in the family, and the purchase of new real estate is not included in the spending plans for the near future
If the attic is not provided with ventilation or it is, but does not work, then soon all this will become known to all family members.
The main problems that arise due to the lack of ventilation in the attic are as follows:
- stale air;
- the appearance of an unpleasant putrefactive aroma;
- mold under the ceiling and on the walls of the attic;
- rotting of roof structures;
- condensation formation;
- icicles and ice hanging from the roof in winter.
An unhealthy microclimate with such signs is provided to all inhabitants. As a result, instead of a bright and comfortable room, we get a hotbed of bacteria, unpleasant odors and colonies of mold, destroying everything that comes in its way.
But this is far from the worst. Such manifestations are the harbingers of an early roof repair that will happen in 3-5 years due to rotten wooden structures, wet insulation and the inability to use the attic for its intended purpose.
The decay of the wooden elements of the roof can lead to their complete destruction and collapse of the roof. Especially if everything is hidden from the inside and the owner did not realize the problem in time
To avoid large expenses after the attic is equipped, it is important to immediately develop a project for its ventilation. This will protect all residents of the house from health problems and save the family budget. What is the solution to the problem of an unexpectedly collapsed roof? It’s good if no one in the house is in the house.
The ventilation of the under-roof space is provided by a complex of devices and events:
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Properly organized ventilation of the space under the roof provides a complete removal of condensate and domestic fumes and its discharge into the atmosphere
In order for condensation not to accumulate under the roof, the roofing system must be properly arranged. First of all, channels should be organized for the removal of moisture, which forms the crate
Equally important is the correct selection of insulating materials: vapor barrier and waterproofing for insulated systems, waterproofing for cold attics
Unobstructed access of air to the under-roof space should be provided by ventilated soffits or a board hemming of cornices with ventilation gaps
The airflow from the roof, from a cold attic or equipped attic is drawn out through a ridge aerator or a regular ridge with ventilation gaps
Roofing systems arranged in a continuous crate made of boards or plate materials are equipped with aerators of various designs
Drying of building structures and the lower part of the roofing pie is carried out by conventional ventilation through dormer and dormer-windows
The windows on the gables are also involved in creating a stable air flow that prevents the appearance of dampness and the formation of fungus.
Ventilation through a panoramic window
The device of the ventilation ducts - air
Perfectly selected insulation material
Ventilated Roofing Spotlights
Skating element with aeration properties
Solid Roof Aerators
Dormer and dormer-windows in ventilation
Ventilation windows on the gables
Attic: what is ventilation
If you consider that the attic is a living room, which is equipped in the attic of the house, then the corresponding requirements must be presented to it. First, it must be safe. Secondly, it is necessary to mount several layers of insulation there so that you can use the room all year round.
Thirdly, you need to think carefully about the roof ventilation of the attic to ensure a comfortable microclimate and good conditions for all residents of the house to stay. Stale and fetid air does not fit into the requirements for living rooms.
In houses with a large area, often in the attic space they equip a bathroom, toilet, bedroom
The ventilation system for the attic is a prerequisite if there is no desire to overpay for roof repairs. Moreover, ventilation of both rooms obtained as a result of attic repair and the roof itself is required to ensure a long service life of roofing materials.
Ventilation used in the attic is:
- natural;
- forced;
- mixed.
The first option involves the use of natural draft resulting from properly equipped vents and channels.
This is the cheapest option possible. For its arrangement, a minimum set of ventilation materials will be required - grilles, aerators, spotlights, ventilation pipes and other elements.
The natural option is most dependent on weather conditions. As a result, instead of a perfectly working ventilation system, condensation can also be obtained and ice in winter
The forced system works thanks to mechanical intervention. It uses fans for inflow and removal, additional equipment for warming cold street air.
This is an expensive option for attic ventilation, especially if you purchase climate equipment with rich functionality - temperature, humidity, humidification, ionization and air heating sensors.
With the mechanical method of attic space ventilation, the main element is a fan
The mixed type of attic ventilation suggests that one process will be mechanical - the influx or removal of air. Most often, the exhaust system is forced, letting in fresh air by gravity.
Subtleties of designing ventilation in the attic
Before proceeding with the installation of aerators or exhaust mechanisms in the attic, you should calculate everything and choose the most suitable option. To do this, take into account the area of the room and its purpose. After all, if here, for example, you have to make a bathroom, then you can’t do without exhaust fans.
Project: when to create it
One of the most important aspects of arranging ventilation is design. It should take place at the construction stage. Otherwise, everything will turn out to be more expensive - you will have to hire another team or to delve into all the intricacies of the process yourself.
When a separate bathroom, kitchen or shower room is equipped in the attic, it is imperative to bring out a separate sewer ventilation duct
If all construction work has already been completed, but there is no ventilation, then you can’t leave everything like that. Be sure to take care of its creation - now it will still cost less than after 2-3 years, when it will be impossible to use the attic. Moreover, the first signs will appear already after 6-8 months after the start of operation of the premises.
The entrance to the attic can be located both inside the house and outside. But this fact does not affect the need to equip a ventilation system. This is not the process to save on.
Moreover, with a reasonable approach, everything will cost many times cheaper than buying new materials for warming the attic, repairing or replacing the roof frame and laying a new coating.
Equipped attic can serve as a full second floor, only the area of the room will be less
How to design ventilation?
Thinking about transforming the attic, you immediately need to consider the ventilation system, choose the best option and develop a specific project.
When designing roof ventilation, you need to take into account the purpose of the future room and its area. It should be remembered that this is necessary not only for the room, but also for under-roof materials. Therefore, it is important to properly lay all the layers of the roof, following the recommendations given by the manufacturer of certain materials of the roofing “cake”.
The ventilation of the roof structure is ensured by the counter grill. Air must enter the gaps between the layers of insulation, moisture and vapor barrier films
First of all, provide options for the influx of fresh air. For this, the correct roof construction is crucial so that you can make one ventilation gap provided by the counter grill. Its total value should be 1/100 of the roof area. To form a gap, a block with sides of 30, 40, 50 mm is used.
Sometimes a counter-lattice is made not continuous, but with gaps - in the form of separate segments. It is built from the eaves overhang to the ridge in order to more efficiently wash the elements of the system with air currents.
In order to optimize the “ventilation” of the timber-framed roof system in the lateral part of the rafters, holes Ø of 2 - 2.5 cm through are additionally drilled. Drilling is carried out after 30 - 50 cm.
Often use roof fans. It is very effective to put inertial wind turbines. They spin from any blow of the wind and pull everything well
Another element that provides a constant flow of fresh air - spotlights under the eaves overhang. Here the peculiarity is that a diffusion film or a microperforated film is not brought to the edge of the cornice. It should immediately break off behind the wall so that a stream of fresh air penetrates calmly.
The soffit binder is convenient to use, easy to mount. They immediately combine the benefits and decorative effect
Another method for inflow is the gap along the entire plane of the roof between the waterproofing and the coating itself. The height of the air may be from 3 to 5 cm.
The size of the hole should be equal at the inlet, outlet and the entire length of this ventilation duct. These rules are customary to observe when constructing insulated roofing systems and roofs without insulation.
The gap must be closed with a special grill to prevent insects, birds and other unwanted visitors from entering the ventilation system
When it was possible to determine the design of the inflow, they begin to develop the most suitable option for air removal.
Most commonly used:
- in the upper part of the roof - ventilation ducts, point aerators, aeration turbines that operate from the smallest gust of wind;
- in the waterproofing film along the entire length along the ridge run, a gap is formed for the free withdrawal of air mass from under the roof;
- if the valley is long, then it is necessary to ensure the flow of air along its entire line into the lower ventilation gap, making a continuous ventilated abutment;
- tend to do continuous ventilation of the skates and ridges.
The total cross-section of ventilation openings, coupled with dormers and aerators, should be approximately 1 / 300-1 / 500 of the attic space.
A ventilated ridge is a part raised above the main roof that provides the necessary clearance. Ready-made item for sale or you can do it yourself
Calculate how many and which ventilation elements will be needed only based on the area of your attic room. All this is very individual - after all, houses and cottages have a very different roof shape, which should also be taken into account when designing a ventilation system for an attic.
Installation instructions for the ventilation system
You can do the installation of the ventilation system yourself or invite specialists with outstanding roofing experience. It is not worth it to turn to cheap craftsmen - the quality of their services may not correspond to even the lowest cost.
If you contact the unfortunate craftsmen, you will have to pay three times - for their work, for a damaged roof, for correcting errors by real experts
In the case when a team of builders will be engaged in installation work, you can voice your preferences to them and check the project that they will subsequently provide. It is necessary to pay attention to whether the proposed version of the inflow and removal of air masses is suitable.
An effective variant of the inflow into the attic is valves that are built into the window structure. They are so arranged that they can ventilate the room even when the sash is closed. Manufacturers offer models for vertical and inclined (skylights) windows.
Windows with valves will ensure reliable supply of fresh air in the right amount to the attic
For the installation of windows, it is better to use the installation service, especially if it is large. If you do it yourself, you can lose the warranty. In the event of any problems, there will be no one to file a claim.
If you decide to engage in self-installation of the ventilation system in the attic, then you will follow the instructions for those elements that need to be installed.
Most often with their own hands they mount spotlights and a ventilated ridge. Depending on the type of material, the set of tools for their installation will also differ. To put aerators on the roof, they usually turn to specialists who have the equipment to make the corresponding holes.
Aerators produce a variety of sizes, shapes, colors.This allows them to fit perfectly, without getting out of the color scheme of the roofing
For the installation of ventilation ducts, a sealant is used to insulate the joints well. In an exhaust system, a fan or an air turbine is often installed. The exhaust fan should be placed directly in the ventilation duct, fixing and connecting it according to the attached instructions.
With the independent arrangement of attic ventilation, it is important to remember that the total area of the exhaust openings should be 20% more than the supply air. Otherwise there will be a problem with traction.
The color and shape of the roof fans allows them to be used for installation with any type of coating
If you have doubts about your own strengths, then it is better to contact specialists who will correctly design and equip the ventilation of the house itself and the attic. This will be the key to a long service life of the attic and the whole house, as well as ensure a healthy atmosphere in the room.
The favorable microclimate of the attic will be a real gift for the next 20-30 years. Ventilated roofs with proper care can last longer.
The video discusses the issues of ventilation of the space under the roof and the problems arising in its absence:
About how you can make a ventilated under-roof space with your own hands:
Having considered the reasons for arranging the ventilation system in the attic and the features of its installation, you can design and implement everything on your own. To do this, you need to allocate free time at the construction stage.
If the construction team is engaged in the construction of the house, then ventilation issues can be entrusted to them by first including this clause in the contract. It is important to remember that after the construction is completed, the organization of ventilation will cost an order of magnitude more expensive.
Tell us about how the ventilation system was built during the arrangement of your own attic. Share useful technological nuances not noted in the article. Please write comments in the block below, post a photo on the topic, ask questions.