Errors During Design and Filling-in of Energy Passport as Part of the Design Documents

A. D. Zabegin, Head of the Building’s Energy Efficiency Sector of Mosgosexpertise

Keywords: design documents, energy passport, energy conservation, specific thermal energy consumption, heated building volume

The article discusses regulatory documents that govern the form and methods of filling-in of energy passport, and main mistakes that occur.

Description:

The article discusses the regulatory documents governing the form and methodology of filling energy passport, and the main mistakes made when filling it out.

Errors when designing and filling out a building’s energy passport

A. D. Zabegin, Head of the sector of energy efficiency of buildings of the Moscow State Expertise, otvet@site

Regulatory documents governing the form and methodology for filling out the energy passport

Federal Law of November 23, 2009 No. 261-FZ “On energy saving and increasing energy efficiency and on introducing amendments to certain legislative acts Russian Federation» established as one of the measures government regulation in the field of energy saving and increasing energy efficiency, requirements for an energy passport (Article 9, paragraph 6). Let's consider which objects are subject to the requirements for energy efficiency and the availability of an energy passport. According to clause 5, art. 11 of the law, these requirements apply to newly constructed, reconstructed and overhauled buildings, structures and structures, with the exception of religious buildings, buildings classified as objects cultural heritage, temporary buildings with a service life of less than two years, individual housing construction projects, auxiliary buildings, individual buildings and structures with an area of ​​less than 50 m2.

In accordance with clause 27 (1) of the provisions of the Government of the Russian Federation of February 16, 2008 No. 87 “On the composition of sections project documentation and requirements for their content”, the energy passport is included in the project documentation in section 10.1 “Measures to ensure compliance with energy efficiency requirements and requirements for equipping buildings, structures and structures with metering devices for energy resources used.”

What does an energy pass include and what form should I use to fill it out? In accordance with clause 10 of the “Rules for establishing energy efficiency requirements”, approved by Decree of the Government of the Russian Federation of January 25, 2011 No. 18, the energy passport of a building includes indicators characterizing the fulfillment of energy efficiency requirements, such as annual specific values ​​of energy resource consumption.

The main document defining the composition and form of the energy passport of the designed facility today is SNiP 23-02–2003 “Thermal Protection of Buildings”, in which Appendix D provides the methodology for filling out the energy passport, and Appendix D contains the form of the passport itself.

I would like to emphasize that Order No. 182 of the Ministry of Energy of the Russian Federation dated April 19, 2010 establishes the requirements for an energy passport based on the results of a mandatory energy audit. The form of Appendix No. 24 of this order takes place during an energy audit carried out on the basis of project documentation, and it should not be accepted as an energy passport as part of the project.

We have decided on the form and methodology for filling out the energy passport as part of the project documentation; now I would like to draw the reader’s attention to the main mistakes made by the designers and developers of the corresponding section of the project documentation.

Main mistakes when filling out an energy passport

The main and most common mistake is the incorrect determination of the heated volume and the heated shell limiting it. To eliminate this error, it is necessary to clearly understand which rooms are included in the heated volume. These are all rooms in which there are heating devices and the internal air temperature maintained by them is above 12 °C (SNiP 23-02–2003, Appendix B, clause 9). Premises with lower temperatures should be excluded from the heated volume, and the heated shell should be limited internal structures(walls or ceilings depending on the location of cold rooms) taking into account the corresponding coefficient - n(Note to Table 6, SNiP 23-02–2003), which allows you to calculate the heat flow through such a structure.

For an example of determining the heated volume, consider a 17-story residential building with a technical floor and an underground parking lot, designed in Moscow. The lower limit of the heated volume in this case will be the ceiling above the parking lot, due to the fact that in accordance with clause 6.3.1 of SP 113.13330.2012 “Car parking. Updated edition of SNiP 21-02–99*" the internal air temperature in the parking lot is maintained at +5 °C and the coefficient n in this case it will be equal n= (20 – 5) / (20 + 28). The lateral border of the volume will be the external walls, windows, stained glass windows and entrance doors. In this case, summer rooms, such as loggias and balconies, are excluded from the heated volume, and walls and window blocks With balcony doors, adjacent to these summer premises. The temperature of the internal air on a loggia or balcony, when glazed, can either be taken equal to the temperature of the external air, or calculated using the heat balance (experience shows that in this case the temperature on the loggia will be 1.5–2 °C higher than the calculated one outside air temperature).

Also, do not forget to include in the heated shell the structures of bay windows (the ceilings under them and the coverings above them), as well as the internal elements of cold entrance vestibules.

The upper limit of the heated volume can be the covering above the upper technical floor, if it has a heating system with heating devices, and the internal ceiling above the last residential floor (floor of the technical floor), if this space is cold or serves for the distribution of communications and collection warm air removed from kitchens and bathrooms (the so-called warm attic). In this case, the temperature of the internal air of the technical floor is determined based on the results heat balance. You should also not forget that the space of staircase and elevator units is in most cases heated, and their walls and coverings extending above the roof level of the technical floor must also be included in the heated volume.

It should be noted that the roofing area of ​​the building must be equal to the sum of the lower floors, except in cases where the heated volume is divided into several volumes, for example in the case of built-in preschool children's institutions, to which, due to the peculiarities temperature regime a separate energy passport is drawn up.

The second mistake can be called the incorrect determination of indicators of usable area (area of ​​apartments in a residential building) and estimated area (area of ​​living rooms in a residential building). This indicator is fundamental, because specific consumption thermal energy for residential buildings, in particular, refers to the indicator of apartment area. This indicator is determined on the basis of Appendix D, SNiP 23-02–2003. It should not include the area of ​​summer premises, parking lots, technical rooms and cold entrance vestibules. Incorrect definition of this indicator leads to an error in the value specific consumption thermal energy up to 50–70%.

The third mistake is the incorrect calculation of the reduced resistance to heat transfer of external enclosing structures. Designers often make mistakes when calculating external walls: the thermal conductivity coefficient indicators for the operating conditions of the region are incorrectly accepted (indicators for the dry state are accepted), the thermal uniformity coefficient is not taken into account, which can be calculated from thermal fields according to the methodology given in clause 9.1 SP 23- 101–2004, or adopted in accordance with GOST R 54851–2011 “Heterogeneous building enclosing structures. Calculation of reduced heat transfer resistance”, types of insulation materials are accepted, the scope of which does not correspond to the designed structures, etc.

Based on clause 8 of SP 23-101–2004, when designing, materials and structures must be used that have been tested in practice and have certificates and technical certificates for the use of both the materials themselves and structures in general, for example, suspended facade systems.

Indicators of heat transfer resistance of translucent structures can be taken either on the basis of SP 23-101–2004, Appendix L, or the corresponding GOST (such as GOST 21519–2003 “Window blocks from aluminum alloys", GOST 30674–99 “Window blocks made of polyvinyl chloride profiles”), and according to the results of certification test reports, if available or with the features of the structures used (clause 5.6 of SNiP 23-02–2003).

It is also necessary to emphasize the need to comply with the content of the section “Measures to ensure compliance with energy efficiency requirements and the requirements for equipping buildings, structures and structures with metering devices for energy resources used” with the requirements of the Government of the Russian Federation of February 16, 2008 No. 87, paragraph 27 (1), in which should contain a list of measures to ensure compliance with established energy efficiency requirements, as well as a graphic part with a diagram (s) of the placement of metering devices for the energy resources consumed by the designed facility.

Arithmetic errors, typos, inconsistencies with other sections of the design documentation and incorrectly selected coefficients when making calculations that occur in every project will be ignored in this article.

It should be taken into account that in accordance with clause 12.7 of SNiP 23-02–2003, the responsibility for reliable information in the energy passport lies with the organization that filled it out. And the indicators of specific heat energy consumption, calculated in the design documentation, are the basis for determining the energy efficiency class, which is assigned to the building when it is put into operation by construction supervision authorities in case of compliance with design solutions (Article 12, Federal Law of November 23, 2009 No. 261- Federal Law).

I hope this article will allow designers to avoid a number of mistakes when designing and filling out an energy passport as part of the design documentation.

Literature

1. Federal Law of November 23, 2009 No. 261-FZ “On energy saving and increasing energy efficiency and on introducing amendments to certain legislative acts of the Russian Federation.”
2. Decree of the Government of the Russian Federation of February 16, 2008 No. 87 “On the composition of sections of project documentation and requirements for their content.”
3. SNiP 23-02–2003 “Thermal protection of buildings”.

Heated area of ​​the building

the total area of ​​floors (including attic, heated basement and basement) of a building, measured within the internal surfaces of external walls, including the area staircases and elevator shafts; For public buildings The area of ​​mezzanines, galleries and balconies of auditoriums is included. (See: TSN 23-328-2001 of the Amur Region (TSN 23-301-2001 JSC). Standards for energy consumption and thermal protection.)

Source: "House: Construction terminology", M.: Buk-press, 2006.

Construction dictionary.

See what “heated area of ​​a building” is in other dictionaries:

Heated area of ​​the building- 1.8. Heated building area m2 Source...

TSN 23-334-2002: Energy efficiency of residential and public buildings. Standards for energy-saving thermal protection. Yamalo-Nenets Autonomous Okrug- Terminology TSN 23 334 2002: Energy efficiency of residential and public buildings. Standards for energy-saving thermal protection. Yamalo Nenetsky autonomous region: 1.5 Degree day Dd °С×day Definitions of the term from various documents: Degree... ... Dictionary-reference book of terms of normative and technical documentation

TSN 23-328-2001: Energy efficiency of residential and public buildings. Standards for energy consumption and thermal protection. Amur region- Terminology TSN 23 328 2001: Energy efficiency of residential and public buildings. Standards for energy consumption and thermal protection. Amur region: 3.3. Automated control unit (ACU) Definitions of the term from various documents: ... ... Dictionary-reference book of terms of normative and technical documentation

TSN 23-311-2000: Energy efficiency of residential and public buildings. Standards for thermal protection of buildings. Smolensk region- Terminology TSN 23 311 2000: Energy efficiency of residential and public buildings. Standards for thermal protection of buildings. Smolensk region: 1.5. Degree days °С ∙ days Definitions of the term from various documents: Degree days 1.10. Living area m2… … Dictionary-reference book of terms of normative and technical documentation

TSN 23-322-2001: Energy efficiency of residential and public buildings. Standards for thermal protection of buildings. Kostroma region- Terminology TSN 23 322 2001: Energy efficiency of residential and public buildings. Standards for thermal protection of buildings. Kostroma region: 1.5. Degree day Dd °С·day Definitions of the term from various documents: Degree day 1.1. A building with efficient... ... Dictionary-reference book of terms of normative and technical documentation

TSN 23-329-2002: Energy efficiency of residential and public buildings. Standards for thermal protection. Oryol Region- Terminology TSN 23 329 2002: Energy efficiency of residential and public buildings. Standards for thermal protection. Oryol region: 1.5 Degree day Dd °С day Definitions of the term from various documents: Degree day 1.6 Glazing coefficient ... Dictionary-reference book of terms of normative and technical documentation

TSN 23-332-2002: Energy efficiency of residential and public buildings. Standards for energy consumption and thermal protection. Penza region- Terminology TSN 23 332 2002: Energy efficiency of residential and public buildings. Standards for energy consumption and thermal protection. Penza region: 1.5 Degree day Dd °C day Definitions of the term from various documents: Degree day 1.6… … Dictionary-reference book of terms of normative and technical documentation

TSN 23-333-2002: Energy consumption and thermal protection of residential and public buildings. Nenets Autonomous Okrug- Terminology TSN 23 333 2002: Energy consumption and thermal protection of residential and public buildings. Nenets Autonomous Okrug: 1.5 Degree day Dd °С×day Definitions of the term from various documents: Degree day 1.6 The glazing coefficient of the building facade... ... Dictionary-reference book of terms of normative and technical documentation

TSN 23-336-2002: Energy efficiency of residential and public buildings. Standards for energy consumption and thermal protection. Kemerovo region- Terminology TSN 23 336 2002: Energy efficiency of residential and public buildings. Standards for energy consumption and thermal protection. Kemerovo region: 1.5 Degree day Dd °С×day Definitions of the term from various documents: Degree day 1.6… … Dictionary-reference book of terms of normative and technical documentation

TSN 23-339-2002: Energy efficiency of residential and public buildings. Standards for energy consumption and thermal protection. Rostov region- Terminology TSN 23 339 2002: Energy efficiency of residential and public buildings. Standards for energy consumption and thermal protection. Rostov region: 1.5 Degree day Dd °C day Definitions of the term from various documents: Degree day 1.6… … Dictionary-reference book of terms of normative and technical documentation

Create a heating system in own home or even in a city apartment - an extremely responsible occupation. It would be completely unreasonable to purchase boiler equipment, as they say, “by eye,” that is, without taking into account all the features of the housing. In this case, it is quite possible that you will end up in two extremes: either the boiler power will not be enough - the equipment will work “to the fullest”, without pauses, but still not give the expected result, or, on the contrary, an overly expensive device will be purchased, the capabilities of which will remain completely unchanged. unclaimed.

But that's not all. It is not enough to correctly purchase the necessary heating boiler - it is very important to optimally select and correctly arrange heat exchange devices in the premises - radiators, convectors or “warm floors”. And again, relying only on your intuition or the “good advice” of your neighbors is not the most reasonable option. In a word, it’s impossible to do without certain calculations.

Of course, ideally, such thermal calculations should be carried out by appropriate specialists, but this often costs a lot of money. Isn't it fun to try to do it yourself? This publication will show in detail how heating is calculated based on the area of ​​the room, taking into account many important nuances. By analogy, it will be possible to perform, built into this page, it will help to perform the necessary calculations. The technique cannot be called completely “sinless”, however, it still allows you to obtain results with a completely acceptable degree of accuracy.

The simplest calculation methods

In order for the heating system to create comfortable living conditions during the cold season, it must cope with two main tasks. These functions are closely related to each other, and their division is very conditional.

• The first is maintaining an optimal level of air temperature throughout the entire volume of the heated room. Of course, the temperature level may vary somewhat with altitude, but this difference should not be significant. An average of +20 °C is considered quite comfortable conditions - this is the temperature that is usually taken as the initial one in thermal calculations.

In other words, the heating system must be able to warm up a certain volume of air.

If we approach it with complete accuracy, then for individual rooms in residential buildings standards for the required microclimate have been established - they are defined by GOST 30494-96. An excerpt from this document is in the table below:

• The second is compensation of heat losses through building structural elements.

The most important “enemy” of the heating system is heat loss through building structures

Alas, heat loss is the most serious “rival” of any heating system. They can be reduced to a certain minimum, but even with the highest quality thermal insulation it is not yet possible to completely get rid of them. Thermal energy leaks occur in all directions - their approximate distribution is shown in the table:

Naturally, in order to cope with such tasks, the heating system must have a certain thermal power, and this potential must not only meet the general needs of the building (apartment), but also be correctly distributed among the rooms, in accordance with their area and a number of other important factors.

Usually the calculation is carried out in the direction “from small to large”. Simply put, the required amount of thermal energy is calculated for each heated room, the obtained values ​​are summed up, approximately 10% of the reserve is added (so that the equipment does not work at the limit of its capabilities) - and the result will show how much power the heating boiler is needed. And the values ​​​​for each room will become the starting point for the calculation required quantity radiators.

The simplest and most frequently used method in a non-professional environment is to adopt a norm of 100 W of thermal energy for each square meter area:

The most primitive way of calculating is the ratio of 100 W/m²

Q = S× 100

Q– required heating power for the room;

S– room area (m²);

100 — specific power per unit area (W/m²).

For example, a room 3.2 × 5.5 m

S= 3.2 × 5.5 = 17.6 m²

Q= 17.6 × 100 = 1760 W ≈ 1.8 kW

The method is obviously very simple, but very imperfect. It is worth mentioning right away that it is conditionally applicable only when standard height ceilings - approximately 2.7 m (acceptable - in the range from 2.5 to 3.0 m). From this point of view, the calculation will be more accurate not from the area, but from the volume of the room.

It is clear that in this case the power density is calculated at cubic meter. It is taken equal to 41 W/m³ for reinforced concrete panel house, or 34 W/m³ - in brick or made of other materials.

Q = S × h× 41 (or 34)

h– ceiling height (m);

41 or 34 – specific power per unit volume (W/m³).

For example, the same room in panel house, with a ceiling height of 3.2 m:

Q= 17.6 × 3.2 × 41 = 2309 W ≈ 2.3 kW

The result is more accurate, since it takes into account not only everything linear dimensions premises, but even in to a certain extent, and features of the walls.

But still, it is still far from real accuracy - many nuances are “outside the brackets”. How to perform calculations closer to real conditions is in the next section of the publication.

You may be interested in information about what they are

Carrying out calculations of the required thermal power taking into account the characteristics of the premises

The calculation algorithms discussed above can be useful for an initial “estimate,” but you should still rely on them completely with great caution. Even to a person who does not understand anything about building heating engineering, the indicated average values ​​may certainly seem dubious - they cannot be equal, say, for the Krasnodar Territory and for the Arkhangelsk Region. In addition, the room is different: one is located on the corner of the house, that is, it has two external walls ki, and the other is protected from heat loss by other rooms on three sides. In addition, the room may have one or more windows, both small and very large, sometimes even panoramic. And the windows themselves may differ in the material of manufacture and other design features. And this is not a complete list - it’s just that such features are visible even to the naked eye.

In a word, there are quite a lot of nuances that affect the heat loss of each specific room, and it is better not to be lazy, but to carry out a more thorough calculation. Believe me, using the method proposed in the article, this will not be so difficult.

General principles and calculation formula

The calculations will be based on the same ratio: 100 W per 1 square meter. But the formula itself is “overgrown” with a considerable number of various correction factors.

Q = (S × 100) × a × b× c × d × e × f × g × h × i × j × k × l × m

The Latin letters denoting the coefficients are taken completely arbitrarily, in alphabetical order, and have no relation to any quantities standardly accepted in physics. The meaning of each coefficient will be discussed separately.

• “a” is a coefficient that takes into account the number of external walls in a particular room.

Obviously, the more external walls there are in a room, the larger the area through which heat losses. In addition, the presence of two or more external walls also means corners - extremely vulnerable places from the point of view of the formation of “cold bridges”. Coefficient “a” will correct for this specific feature of the room.

The coefficient is taken equal to:

— external walls No (interior space): a = 0.8;

- external wall one: a = 1.0;

— external walls two: a = 1.2;

— external walls three: a = 1.4.

• “b” is a coefficient that takes into account the location of the external walls of the room relative to the cardinal directions.

You might be interested in information about what types of

Even on the coldest winter days solar energy still has an impact on the temperature balance in the building. It is quite natural that the side of the house that faces south receives some heat from the sun's rays, and heat loss through it is lower.

But walls and windows facing north “never see” the Sun. The eastern part of the house, although it “catches” the morning sun’s rays, still does not receive any effective heating from them.

Based on this, we introduce the coefficient “b”:

- the outer walls of the room face North or East: b = 1.1;

- the external walls of the room are oriented towards South or West: b = 1.0.

• “c” is a coefficient that takes into account the location of the room relative to the winter “wind rose”

Perhaps this amendment is not so mandatory for houses located on areas protected from winds. But sometimes the prevailing winter winds can make their own “hard adjustments” to the thermal balance of a building. Naturally, the windward side, that is, “exposed” to the wind, will lose significantly more body compared to the leeward, opposite side.

Based on the results of long-term weather observations in any region, a so-called “wind rose” is compiled - graphic diagram, showing the prevailing wind directions in winter and summer time of the year. This information can be obtained from your local weather service. However, many residents themselves, without meteorologists, know very well where the winds predominantly blow in winter, and from which side of the house the deepest snowdrifts usually sweep.

If you want to carry out calculations with more high accuracy, then we can include the correction factor “c” in the formula, taking it equal to:

- windward side of the house: c = 1.2;

- leeward walls of the house: c = 1.0;

- walls located parallel to the wind direction: c = 1.1.

• “d” is a correction factor taking into account the peculiarities climatic conditions region where the house was built

Naturally, the amount of heat loss through all building structures of the building will very much depend on the level winter temperatures. It is quite clear that during the winter the thermometer readings “dance” in a certain range, but for each region there is an average indicator of the most low temperatures, characteristic of the coldest five-day period of the year (usually this is characteristic of January). For example, below is a map diagram of the territory of Russia, on which approximate values ​​are shown in colors.

Usually this value is easy to clarify in the regional weather service, but you can, in principle, rely on your own observations.

So, the coefficient “d”, which takes into account the climate characteristics of the region, for our calculations is taken equal to:

— from – 35 °C and below: d = 1.5;

— from – 30 °С to – 34 °С: d = 1.3;

— from – 25 °С to – 29 °С: d = 1.2;

— from – 20 °С to – 24 °С: d = 1.1;

— from – 15 °С to – 19 °С: d = 1.0;

— from – 10 °С to – 14 °С: d = 0.9;

- no colder - 10 °C: d = 0.7.

• “e” is a coefficient that takes into account the degree of insulation of external walls.

The total value of heat losses of a building is directly related to the degree of insulation of all building structures. One of the “leaders” in heat loss are walls. Therefore, the value of thermal power required to maintain comfortable conditions living indoors depends on the quality of their thermal insulation.

The value of the coefficient for our calculations can be taken as follows:

— external walls do not have insulation: e = 1.27;

- average degree of insulation - walls made of two bricks or their surface thermal insulation is provided with other insulation materials: e = 1.0;

— insulation was carried out qualitatively, based on the carried out thermal calculations: e = 0.85.

Below in the course of this publication, recommendations will be given on how to determine the degree of insulation of walls and other building structures.

• coefficient "f" - correction for ceiling heights

Ceilings, especially in private homes, can have different heights. Therefore, the thermal power to warm up a particular room of the same area will also differ in this parameter.

It won't be a big mistake to accept following values correction factor "f":

— ceiling heights up to 2.7 m: f = 1.0;

— flow height from 2.8 to 3.0 m: f = 1.05;

- ceiling heights from 3.1 to 3.5 m: f = 1.1;

- ceiling heights from 3.6 to 4.0 m: f = 1.15;

- ceiling height more than 4.1 m: f = 1.2.

• « g" is a coefficient that takes into account the type of floor or room located under the ceiling.

As shown above, the floor is one of the significant sources of heat loss. This means that it is necessary to make some adjustments to account for this feature of a particular room. The correction factor “g” can be taken equal to:

- cold floor on the ground or above unheated room(for example, basement or basement): g= 1,4 ;

- insulated floor on the ground or above an unheated room: g= 1,2 ;

— the heated room is located below: g= 1,0 .

• « h" is a coefficient that takes into account the type of room located above.

The air heated by the heating system always rises, and if the ceiling in the room is cold, then increased heat loss is inevitable, which will require an increase in the required thermal power. Let us introduce the coefficient “h”, which takes into account this feature of the calculated room:

— the “cold” attic is located on top: h = 1,0 ;

— there is an insulated attic or other insulated room on top: h = 0,9 ;

- any heated room is located on top: h = 0,8 .

• « i" - coefficient taking into account the design features of windows

Windows are one of the “main routes” for heat flow. Naturally, much in this matter depends on the quality of the window structure itself. Old wooden frames, which were previously universally installed in all houses, are significantly inferior in terms of their thermal insulation to modern multi-chamber systems with double-glazed windows.

Without words it is clear that the thermal insulation qualities of these windows differ significantly

But there is no complete uniformity between PVH windows. For example, a two-chamber double-glazed window (with three glasses) will be much “warmer” than a single-chamber one.

This means that it is necessary to enter a certain coefficient “i”, taking into account the type of windows installed in the room:

- standard wooden windows with conventional double glazing: i = 1,27 ;

- modern window systems with single-chamber double-glazed windows: i = 1,0 ;

— modern window systems with two-chamber or three-chamber double-glazed windows, including those with argon filling: i = 0,85 .

• « j" - correction factor for total area room glazing

Whatever quality windows No matter how they were, it will still not be possible to completely avoid heat loss through them. But it is quite clear that one cannot compare a small window with panoramic glazing almost the entire wall.

First you need to find the ratio of the areas of all the windows in the room and the room itself:

x = ∑SOK /SP

∑ SOK– total area of ​​windows in the room;

SP– area of ​​the room.

Depending on the obtained value, the correction factor “j” is determined:

— x = 0 ÷ 0.1 →j = 0,8 ;

— x = 0.11 ÷ 0.2 →j = 0,9 ;

— x = 0.21 ÷ 0.3 →j = 1,0 ;

— x = 0.31 ÷ 0.4 →j = 1,1 ;

— x = 0.41 ÷ 0.5 →j = 1,2 ;

• « k" - coefficient that corrects for the presence of an entrance door

A door to the street or to an unheated balcony is always an additional “loophole” for the cold

Door to the street or open balcony is capable of making adjustments to the thermal balance of the room - each opening of it is accompanied by the penetration of a considerable volume of cold air into the room. Therefore, it makes sense to take into account its presence - for this we introduce the coefficient “k”, which we take equal to:

- no door: k = 1,0 ;

- one door to the street or to the balcony: k = 1,3 ;

- two doors to the street or balcony: k = 1,7 .

• « l" - possible amendments to the heating radiator connection diagram

Perhaps this may seem like an insignificant detail to some, but still, why not immediately take into account the planned connection diagram for the heating radiators. The fact is that their heat transfer, and therefore their participation in maintaining a certain temperature balance in the room, changes quite noticeably when different types insertion of supply and return pipes.

Illustration	Radiator insert type	The value of the coefficient "l"
	Diagonal connection: supply from above, return from below	l = 1.0
	Connection on one side: supply from above, return from below	l = 1.03
	Two-way connection: both supply and return from below	l = 1.13
	Diagonal connection: supply from below, return from above	l = 1.25
	Connection on one side: supply from below, return from above	l = 1.28
	One-way connection, both supply and return from below	l = 1.28

• « m" - correction factor for the peculiarities of the installation location of heating radiators

And finally, the last coefficient, which is also related to the peculiarities of connecting heating radiators. It is probably clear that if the battery is installed openly and is not blocked by anything from above or from the front, then it will give maximum heat transfer. However, such an installation is not always possible - more often the radiators are partially hidden by window sills. Other options are also possible. In addition, some owners, trying to fit heating elements into the created interior ensemble, hide them completely or partially with decorative screens - this also significantly affects the thermal output.

If there are certain “outlines” of how and where radiators will be mounted, this can also be taken into account when making calculations by introducing a special coefficient “m”:

So, the calculation formula is clear. Surely, some of the readers will immediately grab their head - they say, it’s too complicated and cumbersome. However, if you approach the matter systematically and in an orderly manner, then there is no trace of complexity.

Any good homeowner must have a detailed graphic plan of his “possessions” with dimensions indicated, and usually oriented to the cardinal points. The climatic features of the region are easy to clarify. All that remains is to walk through all the rooms with a tape measure and clarify some of the nuances for each room. Features of housing - “vertical proximity” above and below, location entrance doors, the proposed or existing installation scheme for heating radiators - no one except the owners knows better.

It is recommended to immediately create a worksheet where you can enter all the necessary data for each room. The result of the calculations will also be entered into it. Well, the calculations themselves will be helped by the built-in calculator, which already contains all the coefficients and ratios mentioned above.

If some data could not be obtained, then you can, of course, not take them into account, but in this case the calculator “by default” will calculate the result taking into account the least favorable conditions.

Can be seen with an example. We have a house plan (taken completely arbitrarily).

Region with level minimum temperatures within -20 ÷ 25 °C. Predominance of winter winds = northeast. The house is one-story, with an insulated attic. Insulated floors on the ground. The optimal diagonal connection of radiators that will be installed under the window sills has been selected.

Let's create a table something like this:

Then, using the calculator below, we make calculations for each room (already taking into account the 10% reserve). It won't take much time using the recommended app. After this, all that remains is to sum up the obtained values ​​for each room - this will be the required total power of the heating system.

The result for each room, by the way, will help you choose the right number of heating radiators - all that remains is to divide by the specific thermal power of one section and round up.