Cold attic pie

Any well-insulated home must have a cold attic, especially in areas with variable climates. It is the area that is kept cool to avoid heat loss and moisture accumulation between the ceiling of the top floor and the roof. This design lowers energy expenses, safeguards the structural integrity of the roof, and aids in maintaining a constant indoor temperature.

An ice-free attic is essential for preventing ice dams in areas with harsh winters. When snow melts on a warmer roof and then refreezes at the eaves, where the roof is colder, it creates these dams. The roof stays consistently cold when the attic is kept cold, avoiding uneven melting and refreezing that can harm shingles and cause leaks.

To keep an attic cold, proper ventilation and insulation are essential. While ventilation allows for air circulation that prevents moisture buildup, insulation aids in keeping the heated air inside the living spaces below. This combination increases the home’s overall energy efficiency while also protecting the roof.

In "Cold Attic Pie," an article published in "All about the roof," we discuss how properly insulating your attic can improve comfort and energy efficiency considerably. This article tries to help homeowners understand the significance of a well-insulated attic in maintaining stable indoor temperatures, lowering heating and cooling costs, and preventing problems like moisture buildup and ice dams during the colder months by focusing on efficient insulation techniques and materials.

Roof device with cold attic

The majority of pitched roofs in our nation are built with a chilly attic. The attic’s air temperature, which shouldn’t vary significantly from the outside air temperature of the house, is the source of the name. When positioned correctly, this attic device creates a sizable buffer air zone that lets you efficiently control the attic’s temperature.

The design of the cold attic

Many people consider creating a cold attic or attic beneath the house while the roof is being built. The simplest method for organizing a cold attic on a roof. The attic’s construction will be much more expensive and labor-intensive. Still, there’s no denying that adding an attic will greatly increase the living space.

The primary elements of the roofs with cold attics are as follows:

1. roofing;
2. attic external walls (applicable for gable roofs with pediments);
3. insulated overlap between the living room and the attic.

Ridge produces and cornices allow for ventilation. The air that enters the cornice and exits the horse is referred to as the supply and exhaust, respectively. Furthermore, ventilation can be achieved via the auditory windows located on roof slopes or gables. Blind grates will be installed in the windows to control the amount of ventilation.

There are no waiting areas because the auditory windows are situated on the opposing slopes of the roof.

Shapes for auditory windows include semicircular, triangular, and rectangular shapes. Their upper portion should not be lower than 1.75 m from the attic floor, and their lower part should not be higher than 0.8–1.0 m from the attic ceiling floor. They can also be used as a way out of the house to inspect the chimney, ventilation system, and roof.

Steam and thermal insulation of the cold attic

Optimizing heat loss through the attic overlap is crucial for a roof with a cold attic. A vapor barrier is required for ceilings made of reinforced concrete or wood. It is placed on top of the overlap and shields the insulation from vapors that could penetrate the home’s ceiling and cause fondance in the heat insulator. Materials in bulk and plates can be utilized as insulation. The insulation beams, ceilings, and vapor barrier make up the ceiling pie.

The ceiling overlap frequently uses the following kinds of heat insulators:

• polystyrene and foam slabs;
• mineral wool slabs or mats;
• expanded clay granules;
• slag fuel or granular;
• sawdust with lime or clay;
• pumice.

Using the table below, determine the required layer thickness of insulation based on the estimated winter temperature.

The winter temperature is determined using the relevant climatic cards or by the regions of the Russian Federation using SNiP 2.01.01-82 (construction climatology and geophysics).

A plank floor is constructed for the attic passageways on top of the insulation that is installed between the ceiling’s lags or beams. Floor boards are typically 25–35 mm thick, and lags are 50 mm thick.

Soft or semi-hard insulating materials are thought to be the best for ventilated attic spaces.

The waterproofing apparatus for the attic

Many experts believe that waterproofing roofs with cold attics is a contentious topic. There are those who insist on having waterproofing beneath roofing material, and there are those who strongly advise against it. In this case, a lot relies on the kind of roofing material and the slope of the roof’s inclination.

The most common causes of corrosion on metal roofs are condensate leaks or tiny leaks. Thus, we would like to remind you that one of the most important factors in the fight against the resulting condensate is ventilation.

Experts advise installing the superdiffusion membranes on gentle metal roofs. When rain or snow is blowing, it will keep moisture from getting outside the roof. There is always a chance of minor leaks, regardless of how well the roof is installed. For this reason, you will get extra protection against moisture getting on the insulation in the cold attic’s overlap if you slightly overpay.

The heat-insulating qualities of hydrophobic heaters are greatly diminished by potential leaks or condensation.

Waterproofing may be rejected, for instance, if slate is utilized for the roofing. Additionally, a corrugated board with an anti-condensate coating that can hold one liter of water per square meter is available on the market. As for us, we always advise applying waterproofing membranes since they are the least expensive and most straightforward extra measure to shield your roof from potential leaks.

The counterparty is used when installing membranes that provide waterproofing. In addition to serving as a fixing rail, its height creates the opening required to allow air to pass through the subcutaneous space. The cold attic crate device is the same as the one used on insulated roofs. The kind of roofing that is installed depends on the size of the crate and its step.

The frigid attic temperature range

The proper temperature-humidity balance must be maintained in the attic to prevent the formation of ice and icicles on the roof. Significant heat losses through the ceiling occur when the thermal insulation material is not thick enough. Snow thaws and ice forms due to warm air heating the roofing. By choosing an appropriate layer of insulation, this can be prevented.

By measuring the temperature of the upper layer of insulation, you can assess the heat insulator’s efficiency. The insulation submerges the electronic thermometer by 10–20 mm.

As you can see, there is no unique constructive complexity in the cold attic cake device. Ensuring adequate ventilation intensity and a sufficient thickness of the heat-insulating layer in the ceiling overlap are the primary tasks.

Pie and design in a cold attic. In the chilly attic, steam cleaned the waterproofing and ceiling. ideal temperature in the loft.

Roof pie for cold attic

A combined attic or attic and a cold attic are the two different kinds of attic spaces. The insulation in the cold attic is arranged horizontally along the attic floor, and the temperature there is comparable to that of the street.

The temperature inside the cold attic should not exceed 4 ° C of the outdoor temperature (rules and norms of technical operation of the housing stock, resolution dated September 27, 2003 No. 170, p. 3.3.2), t.e. If the temperature on the street is -15 ° C, then in the attic it should be no more than -11 ° C. If this difference is greater, then, for example, at an outdoor temperature -5 ° C, the slope will heat up, the snow on the roof will tent and drain onto the cornice. The cornice will not heat up, t.To. There is no warm room under it, and the water on it will turn into ice, forming icicles. The more ice is formed on the cornice, the greater the chances of leaks, above the load on the roof and higher the danger of ice disruption, which can lead to tragic consequences. All this reduces the life of both the roofing and the roof in general.

The overlap between the attic and the premises must first be insulated in order to maintain a normal temperature regime in a cold attic. The location of the house is the primary factor taken into account when calculating the insulation thickness. Underheld ventilation is the second most crucial requirement for adhering to the attic space’s temperature regime.

Apart from insulation and ventilation, the temperature regime in the attic area is also influenced by the following: the open hatch covers, the exhaust from the kitchen and bathroom ventilation pipes, the hot water supply that isn’t invited into the attic, and so on.

There are two pieces to the roofing pie for the chilly attic. The living room and attic overlapped in the first section. There is a slope in the second section.

Depending on the type of ceiling, the first portion of the roof pie looks like this:

The purpose of the vapor barrier is to keep moisture-laden air out of the insulation and into the room. The best material to use on a concrete basis is bitumen roll material with overflowing overflows. The lags employ film vapor barriers and require the overlap to be glued together with sealing ribbons. It is required to use vapor barrier films such as D-Folie B, D-Folie B 90, or D-Folie Br.

Several layers of insulation are installed with space between joints to prevent cold bridges.

Heat and moisture weathering are prevented by the hydraulic protection membrane. Condensate, snow blown into the attic space, and potential leaks can all result in the formation of moisture. Use of the D-Folie A 150 or D-Folie A 100 superdiffusion membranes is required for hydraulic protection.

In any case, covering the insulation with plywood or boards on top is not advised, regardless of the type of overlap. It is preferable to provide pathways from the boards without completely closing the insulation if it is necessary to occasionally walk through the attic space.

This is how the second section of the roof pie made of flexible tiles in the chilly attic looks:

The device of the attic roof pie with insulation

It is impossible to tell a house with a pitched roof—under which the attic is located—from other buildings with an attic from the outside, with the exception of the attic windows. However, there are some noticeable variations if you look closely at the roof design. To prevent warm air from escaping from the residential floor, the attic premises are insulated only from the side of the ceiling. There are numerous layers in the attic roof pie that enable you to establish a microclimate that is ideal for living under the roof.

Constructive features

Let’s start by defining what a roofing pie is. These are the essential structural layers of the roof, installed in a specific order to provide insulation for the building, defense against moisture and condensation from the street, and a foundation upon which to install the roof.

The warm attic and the cold attic have very different roofing pie. There are fewer structural layers used in the first instance. Typically, these include roof coating, rafters, waterproofing, and crates. The following layers, which are arranged from the bottom up, make up the proper roofing pie when placing residential attic spaces beneath a roof:

• interior decoration of the room;
• vapor barrier layer;
• rafter system and thermal insulation material that is laid between the rafters;
• waterproofing carpet;
• the lumen for ventilation of the subcutaneous space (it is formed by laying the counter -attack);
• crate;
• roofing, namely chosen roofing material.

Since each of the aforementioned layers has a specific function, its absence or improper installation can result in significant heat losses and increased home heating expenses. Condensate buildup causes the insulation to become drew, which leads to the rapid destruction of the rafter system’s supporting structures.

Crucial! It is important to keep in mind that selecting the right material for the job in accordance with the specifics of the roof structure and the local climate is just as important as having a certain layer present and installing it correctly.

Features of each layer

The design elements of the attic pie in layers, along with the subtleties of material selection and placement, will be discussed next. Leaving the room, we will take into account every layer of the attic roof’s design.

The interior decoration is the first layer, and it is situated on the side of the room. You can use plastic panels, wooden lining, drywall sheets, and other finishes for these purposes. Of all the materials used to decorate the attic, wood and drywall have the advantage because they naturally control the room’s humidity, creating a comfortable microclimate.

From below, the vapor barrier is fastened to the rafter system. The internal roof structures and insulation must be shielded from the formation of condensation caused by temperature differences between the interior of the room and the street.

Take note! Condensate moisture builds up in insulation due to a lack of vapor barrier or a low-quality one. The room will be cold because the insulation is unable to carry out its thermal insulation duties due to damp.

Using a construction stapler, vapor barrier rolled materials are rolled in the direction of the rafters and fastened to them. In this instance, 150 mm of strip overlap is required. Additionally, special ribbons or regular tape are used to seal the joints in the material strip.

The vapor barrier is made of the following materials:

1. The most affordable and inexpensive vapor barrier is Pergamin. Over the years, its properties to protect against condensate moisture are reduced, so it is better not to use it.
2. Special vapor barrier membrane. This is a plastic film that can have additional reinforcing and reflecting layers. She copes with her tasks perfectly and does not sag.
3. Foil vapor barrier. This is the most expensive material, but in addition to protection against moisture, it allows you to effectively maintain heat in the room due to the reflective layer. The foil film must be attached with a gap from the insulation of 10-20 mm. To obtain this clearance before fixing the film on the rafters, slats are packed with the corresponding thickness.

It is important to understand that the vapor barrier is attached to the rafters with a small sag of approximately 2 mm because it should not fit tightly against the insulation placed between the rafters.

Elements composed of at least one variety of coniferous wood with a moisture content of no more than 15% are used in the construction of the rafters of a pitched roof in a private home. 150×50 mm is the ideal rafter section size. To effectively insulate the attic roof in our country’s middle climate zone, 200 mm thick heat-insulating material must be used. As you can see, the rafters’ 15 cm height will not be sufficient, so they can be joined from below by a beam having a 50 x 50 mm cross section.

The width of the thermal insulation material used, the type of roofing, and the roof design all affect the rafter system installation process. It’s also important to keep in mind that one element’s cross section should increase with the rafter system’s step size. The ideal step for rafters with a 5×15 cm section is 800-900 mm.

Crucial! The roof carrier’s entire wooden structure needs to be sealed against rot and fire. They receive a pre-treatment of antiseptics and anti-piren to achieve this.

The insulation cake is the most crucial component of the attic roof design because it determines both the level of soundproofing of the space and how comfortable it is to live in. Typically, they employ the following to insulate the pitched structures from heat:

• Mineral slabs. They are made on the basis of basalt fiber, quite dense, not flammable and preserve heat well.
• Fiberglass is non -combustible, environmentally friendly material. Its disadvantage is the instability of the structure and the possibility of sagging.
• Foam is an inexpensive effective material that does not absorb moisture at all, but when burning, it releases toxic compounds.
• Polistyle foam is a very light, non -combustible and non -toxic material that does not accumulate moisture. However, it has increased vapor permeability, so in the summer on the attic floor there may be increased humidity. Polystyrene foam due to high rigidity is difficult to lay on complex areas of the roof.

Advice: Soft mineral wool plates based on the base work best for attic insulation. They fit snugly against the rafters without creating cold bridges and are simple to install in intricate spaces.

The thickness of the thermal insulation material is computed separately for every construction area. 150 mm is the minimum thickness of insulation. You must use thermal insulation material with a minimum thickness of 20 cm if you live in an area with severe winters. In this instance, the rafters’ dry wood is the only guideline used for laying insulation. If not, moisture will seep into the thermal insulation material, decreasing its efficiency.

The primary goal of waterproofing is to keep water vapor from evaporating from thermal insulation material and to shield the insulation from moisture entering from the roof. Because a vapor barrier film cannot pass water vapor, it is not appropriate for these uses. Roof waterproofing requires the use of particular materials:

1. Diffusion membranes. These are films with microscopic holes in the shape of a funnel. The material is laid so that a wide part of the funnel will be turned to the insulation, and narrow towards the roofing. In this case, it is necessary to create two ventilation gaps and lay the material from the insulation at a small distance so that the funnels do not clog with water steam. These membranes can only be used with those roofing coatings that are not afraid of moisture collecting from the back.
2. SuperDiffusion membranes. The effectiveness of this material does not require the arrangement of the air gap on the side of the insulation. Such films are suitable for houses, where the roof is covered in an already inhabited building. The membranes protect well from the wind.

Crucial! Since the back of both types of membranes should be consistently shielded from condensation, they cannot be used with coatings from metal tiles and Euro-shifers. Yet these membranes are perfect for coatings composed of conventional, soft tiles.

1. Condensate films are used for roofs from euro -shifers and metal tiles, since they do not pass water vapor. At the same time, excess moisture from thermal insulation material accumulates on the vile side and is displayed through the ventilation clearance. In such structures, you need to perform a second ventilation gap between the waterproofing carpet and the coating so that the condensate does not accumulate on the back of the roof.

Restraint and container

If the subcutaneous space needs to be ventilated, the counterparty’s rails are filled and placed on top of the waterproofing carpet. Use a beam with a cross-section of 30 to 40 mm that is nailed in the direction of the rafters to accomplish this.

A layer of crate is placed after this. It may be sparse or continuous. The first option is constructed of moisture-resistant plywood or OSP and has soft roofing, such as flexible tiles. In a continuous crate, you should allow two to three millimeters for deformation between the components. In the second instance, they use 25 mm thick boards that are nailed in steps of 30 to 40 centimeters across the rafters. The roof is then installed.

Layer descriptions and the attic roof pie’s design features. Vapor barrier, insulation, waterproofing, and rafter system. Crate and restraint.

It is essential to comprehend the cold attic issue if you want to keep your house cozy and energy-efficient. Homeowners can prevent moisture buildup all year round and drastically cut down on heat loss during the winter by taking care of this issue.

The key to preventing cold attic syndrome is adequate attic insulation. In addition to maintaining a steady interior temperature, good insulation keeps ice dams from forming on the roof, which over time can do serious harm.

Think about things like the R-value, which represents the material’s thermal resistance, when selecting insulation materials. Better insulation is provided by higher R-values. Furthermore, controlled humidity levels and the avoidance of condensation, which can result in mold growth and structural damage, depend on adequate ventilation.

Maintaining the attic in good condition requires routine maintenance and inspections. Look for any indications of leaks, insulation gaps, or structural damage to the roof. Homeowners can avoid expensive repairs and increase overall energy efficiency by making repairs quickly.

In conclusion, a combination of insulation, ventilation, and routine maintenance is needed to solve the cold attic issue. Through the implementation of these measures, homeowners can guarantee the longevity of their home’s roofing system, lower energy costs, and create a more comfortable living environment.

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