Heat calculation by building volume

Knowing how heat is distributed and calculated in our living spaces is crucial for keeping our homes warm and comfortable during the colder months. Determining the heat requirements based on the building’s volume is one of the process’s core components. It is possible to achieve the best possible comfort levels and energy efficiency by taking into account various factors such as insulation, climate, and the area that needs to be heated.

Estimating the building’s size is not the only step in the process of calculating heat based on volume. It necessitates a thorough analysis that considers all the factors that affect heat gain and loss. These variables include the building materials chosen, the quantity and dimensions of windows, doors, and other apertures, as well as the region’s unique climate.

Heat retention in a building is greatly aided by insulation. Proper insulation reduces heat loss through the walls, floors, and attic, which lowers the energy required to keep the interior temperature comfortable. Comprehending the distinct insulating characteristics of various materials and being aware of their installation locations and methods can greatly influence the total heat computation.

Moreover, taking the building’s volume into account enables a more precise evaluation of the heating needs. When calculating heat based on volume, all dimensions of the living area are taken into consideration, unlike when relying solely on square footage, which might ignore vertical space. This method gives a more accurate estimate of the energy required to efficiently heat the entire area.

Through an exploration of the nuances of heat calculation by building volume, homeowners can arrive at well-informed decisions regarding energy use and heating systems. Learning how to calculate heat based on building volume enables people to design warmer, more energy-efficient homes through the use of smart heating controls, insulation optimization, and appliance selection.

Building Type	Volume (m^3)
Single-family house	Calculate by multiplying length, width, and height
Apartment building	Add up volumes of all units

Calculation of heat load for heating a building: formula, examples

Whether designing a heating system for a residential or commercial building, it is essential to perform accurate calculations and create a circuit diagram for the heating system. Experts advise paying close attention to the computation of the fuel consumption and heat released at this point, as well as the potential heat load on the heating circuit.

Heat load: what is it

This term refers to the quantity of heat that heating appliances release. The purchase and installation of unnecessary heating system components can be avoided with a preliminary heat load calculation. Additionally, this computation will support the accurate and equitable distribution of the released heat throughout the building.

These computations involve a lot of subtleties. For instance, the building’s material, the area, thermal insulation, etc. Experts strive to consider as many variables and attributes as they can in order to produce a more precise outcome.

An inaccurately calculated heat load causes the heating system to operate inefficiently. Even in cases where it becomes necessary to remodel portions of an existing construction, unforeseen expenses will inevitably arise. Additionally, housing and community organizations use data on the heat load to determine the cost of services.

Main factors

A well-designed and calculated heating system should compensate for any heat losses and keep the room at the desired temperature. When determining a building’s heating system’s heat load, the following factors must be considered:

– Is the building intended for residential or industrial use?

– An explanation of the building’s structural components. These consist of the roof, ventilation system, doors, walls, and windows.

The size of the residence. The heating system should be more powerful the larger it is. The area of doorways, windows, external walls, and the volume of each interior room must all be considered.

– The availability of rooms with specific uses (sauna, bath, etc.).

– Level of technological device equipment. that is, whether a hot water supply, air conditioning, ventilation, and heating system type are present.

– The temperature schedule for a specific room. For instance, it’s not necessary to keep a person’s temperature comfortably in rooms meant for storage.

The quantity of hot water supply locations. The load on the system increases with their number.

The total area covered by glass. French windows let in a lot of cold air into a room.

– Extra prerequisites. This can include the quantity of bathrooms, balconies, and loggias in residential buildings. In the industrial sector, factors include shift work, the number of working days in a year, the technological chain leading to production, etc.

– Local climate circumstances. Heat losses are calculated taking into account street temperatures. There won’t be much energy used to make up for small temperature variations. While a large portion of its expenditure will be necessary outside the window at -40 o C.

Peculiarities of existing methods

SNiPs and GOSTs contain the parameters needed to calculate heat load. Additionally, these have unique heat transfer coefficients. The numerical characteristics pertaining to a particular heating radiator, boiler, etc. are extracted from the passports of the equipment that is part of the heating system. Additionally, customarily:

– The heat consumption measured during a single hour of heating system operation at maximum power,

Maximal heat output from a single radiator,

– total amount of heat used during a specific time period (usually a season); if hourly computation of the heat network’s load is required, the computation must account for variations in temperature throughout the day.

The computations are contrasted with the system’s overall heat output area. The number is very precise. There are some exceptions. For instance, it will be important to consider reducing heat consumption in residential buildings at night and on weekends and holidays for industrial buildings.

There are different levels of precision in the methods used to calculate heating systems. Rather intricate computations must be used in order to reduce the error. If maximizing the heating system’s expenses is not the goal, less precise schemes are employed.

Calculating heat based on volume is essential to knowing how to heat and insulate a house effectively. This technique determines how much heat is required to keep interior temperatures comfortable. Homeowners can choose heating systems and insulation materials with knowledge by taking into account factors such as the space’s size and insulation capabilities. In the home, calculating heat by volume promotes sustainability and comfort by optimizing energy use and cutting heating expenses.

Basic calculation methods

These days, there are several methods available for calculating the heat load required to heat a building.

Three main

1. The calculation is based on aggregated values.
2. The indicators of the structural elements of the building are taken as a base. Here the calculation of heat losses for heating the internal air volume is also important.
3. All objects entering the heating system are calculated and summarized.

One approximate

There is one more choice. Because the values are either insufficient or extremely averaged, there is a sizable error. Qfrom = q0 * a * VH * (tEH – tNRO) is the formula in question, where:

• q₀ – Specific heat characteristic of the building (most often determined by the coldest period),
• a – correction factor (depends on the region and is taken from ready-made tables),
• V_H – volume calculated on the external planes.

Example of a simple calculation

A straightforward parameter ratio can be used for a building with standard parameters (ceiling height, room size, and good thermal insulation characteristics), with a regional correction applied for the coefficient.

Assume for the moment that the residential property is 170 square meters in size and is situated in the Arkhangelsk region. м. There will be a heat load of 17 * 1.6 = 27.2 kWh.

Numerous significant factors are ignored in such a definition of heat loads. For instance, the building’s structural characteristics, temperature, the quantity of walls, the proportion between the area of the walls and the window openings, etc. As a result, these computations are inappropriate for significant heating system projects.

Calculation of the heating radiator by area

It is dependent upon the material used to make them. Cast iron radiators are used far less frequently than bimetallic, aluminum, and steel radiators nowadays. Every one of them has a unique rate of heat output, or heat transfer. Bimetallic radiators with 500 mm between the axes typically have 180–190 W. Aluminum radiators have nearly identical indicators.

The radiators that are described have their heat output calculated for each section. Steel plate radiators do not require disassembly. As a result, the size of the entire unit determines their heat output. For instance, a double row radiator measuring 1 100 mm in width and 200 mm in height will produce 1 010 W of heat, while a steel panel radiator measuring 500 mm in width and 220 mm in height will produce 1 644 W.

The following fundamental factors are taken into account when calculating a heating radiator by area:

– the standard ceiling height of 2.7 meters,

– heat output (100 W per square meter),

One wall on the outside.

According to these calculations, 1000 W of heat power are required for every 10 square meters. This outcome is divided by one section’s heat output. The required number of radiator sections is the answer.

Both decreasing and increasing coefficients have been developed for the southern and northern regions of our country.

Average calculation and exact calculation

The following scheme is used to calculate the average after accounting for the factors mentioned. A 20 square foot room should receive 2,000 W of heat flux if one q q. m needs 100 W. A typical bimetallic or aluminum radiator with eight sections can handle approximately 150 W of power. 2,000 divided by 150 yields 13 sections. However, this is only a total heat load calculation.

The precise one appears a little intimidating. Nothing very difficult. This is the equation:

• q₁ – type of glazing (conventional =1).27, double = 1.0, triple = 0.85);
• q₂ – wall insulation (weak, or missing = 1.27, a wall built in 2 bricks = 1.0, modern, high = 0.85);
• q₃ – ratio of the total area of window openings to the floor area (40% = 1.2, 30% = 1.1, 20% – 0.9, 10% = 0.8);
• q₄ – street temperature (minimum value is taken: -35 o C = 1.5, -25 o C = 1.3, -20 o C = 1.1, -15 o C = 0.9, -10 o C = 0.7);
• q₅ – number of external walls in the room (all four = 1.4, three = 1.3, corner room = 1.2, one = 1.2);
• q₆ – type of design room above the design room (cold attic = 1.0, warm attic = 0.9, residential heated space = 0.8);
• q₇ – ceiling height (4.5 м = 1.2, 4.0 м = 1.15, 3.5 м = 1.1, 3.0 м = 1.05, 2.5 м = 1.3).

Any of the methods that have been described can be used to determine an apartment building’s heat load.

Example calculation

These are the requirements. During the cold season, the lowest temperature is -20 o C. This 25 square meter room has two brick walls, triple glazing, double glazed windows, a 3.0 m ceiling, and an unheated attic. This is how the calculation will be done:

Q is equal to 100 W/m 2 × 25 m 2 × 0.85 × 1 × 0.8(12%) × 1.1 × 1.2 × 1 × 1.05.

Divide the result, 2,356.20, by 150. Consequently, it transpires that sixteen sections must be installed in the room with the given dimensions.

If it is necessary to calculate in gigacalories

In the event that the open heating circuit lacks a heat meter, the building’s heat load is determined using the formula Q = V * (T1 – ΢2) / 1000, where:

• V – the amount of water consumed by the heating system, calculated in tons or m 3 ,
• Т₁ – The number indicating the temperature of hot water is measured in o C and the temperature corresponding to a certain pressure in the system is taken for calculations. This indicator has its own name – enthalpy. If it is not possible to take temperature readings in a practical way, an averaged reading is used. It is in the range of 60-65 o C.
• Т₂ – cold water temperature. It is rather difficult to measure it in the system, so constant indicators depending on the temperature regime on the street have been developed. For example, in one of the regions, in the cold season this indicator is taken as 5, in summer – 15.
• 1 000 – coefficient to obtain the result immediately in gigacalories.

The heat load (gcal/hour) in the event of a closed circuit is computed differently:

• α is a coefficient designed to correct climatic conditions. It is taken into account if the street temperature is different from -30 o C;
• V is the volume of the building according to external measurements;
• q_о – specific heating value of the building at a given t_н.р = -30 o C, measured in kcal/m 3 *C;
• t_в – is the calculated internal temperature in the building;
• t_н.р – is the design street temperature for the design of the heating system;
• K_н.р – infiltration coefficient. It is conditioned by the ratio of heat losses of the design building with infiltration and heat transfer through external structural elements at the street temperature, which is set within the framework of the project being prepared.

Although the heat load calculation ends up being somewhat expanded, this is the formula provided in the technical literature.

Thermal imaging

Thermal imaging surveys of the building are being used more and more to increase the efficiency of the heating system.

These tasks are completed during the day’s gloomiest hours. The temperature differential between the room and the street should be at least 15 o in order to get a more accurate result. All incandescent and daylight lamps are turned off. As much as possible, furniture and carpets should be removed because they can cause the device to fall and cause error.

The survey is completed slowly, and every data point is meticulously recorded. The plan is straightforward.

The initial phase of the project is completed indoors. Moving the device gradually from the doors to the windows requires close attention to joints and corners.

The building’s exterior walls are surveyed using thermal imaging technology in the second stage. The joints are likewise examined closely, particularly the one that connects to the roof.

Data processing is the third step. The device completes the task first, after which the readings are sent to the computer for further processing by the relevant applications, yielding the desired outcome.

At the conclusion of the project, if the survey was conducted by a licensed organization, it will provide a report that includes required recommendations. If the work was completed by hand, you will need to rely on your expertise and possibly the assistance of the Internet.

Calculation of space heating by volume

Many factors need to be considered when installing a heating system in a building, ranging from the caliber of consumables and functional equipment to the computation of the node’s required power. Therefore, a calculator will come in handy when calculating the heat load required, for instance, to heat the building. Numerous techniques are used, and a great deal of nuance is taken into consideration. As a result, we advise that you investigate this matter more thoroughly.

Averages as a basis for calculating the heat load

You must ascertain the following information in order to compute space heating by coolant volume accurately:

• value of the required amount of fuel;
• capacity of the heating unit;
• efficiency of the set type of fuel resources.

Housing and communal enterprise specialists have developed a unique methodology and program that eliminates laborious calculation formulas. With this program, you can literally calculate the heat load for heating and other data required in the design of the heating unit in a matter of minutes. Furthermore, regardless of the fuel source type, this methodology can be used to accurately calculate the cubic volume of the heat carrier for heating a specific room.

Basics and peculiarities of the methodology

Employees of cadastral firms frequently use this type of methodology, which can be applied with a calculator to calculate the heat load for heating a building, to assess the technological and financial viability of various energy-saving initiatives. Furthermore, energy-efficient processes can be initiated and new functional equipment added to projects with the aid of such computation and computational methods.

So, experts use the following formula to determine the heat load for heating a building:

• a – coefficient, which shows the difference in the temperature difference of the outside air when determining the efficiency of the heating system;
• t_i ,t₀ – temperature difference between indoor and outdoor temperatures;
• q₀ – Specific exponent, which is determined by additional calculations;
• K_u.p – infiltration coefficient, which takes into account all kinds of heat losses, from weather conditions to the lack of an insulation layer;
• V – volume of the building that needs heating.

How to calculate the volume of the room in cubic meters (m 3 )

The very basic formula simply requires multiplying the room’s length, width, and height. This option, though, is limited to figuring out the structure’s cubature—which is either square or rectangular in shape. This value is calculated slightly differently in other situations.

The task becomes slightly more difficult if the room has an irregular shape. In this instance, it is required to make all the measurements beforehand and divide the room area into simple figures in order to calculate the cubature of each room. All that’s left to do is total the results. The same units of measurement, such as meters, should be used for all calculations.

The cubature is calculated as the product of the horizontal cross-section of the house (here we refer to the indicator, which is taken from the level of the first floor surface) to its full height, taking into account the highest point of the attic’s insulation layer, if the structure for which an aggregated calculation of the building’s heat load is made has an attic.

The existence of cellars or basements must be taken into consideration before determining the room’s volume. In addition, these rooms must be heated; if they are, the cubic area of the house should be increased by 40%.

The infiltration coefficient can be ascertained by Ku.p. using the following formula as a guide:

• g – exponent of the acceleration of free fall (reference data from SNiP);
• L – height of the construction;
• W₀ – conditionally dependent value of wind speed. This value depends on the location of the building and is selected according to SNiP.

Possible energy losses

Every single kind of energy loss needs to be considered in order to get the most accurate result. Thus, credit goes to the following primary ones:

• through the attic and roof, if they are not properly insulated, the heating unit loses up to 30% of heat energy;
• If there is natural ventilation in the house (chimney venting, regular airing, etc.), it is necessary to take into account all types of energy losses.п.) consumes up to 25% of heat energy;
• if wall ceilings and floor surface are not insulated, up to 15% of energy can be lost through them, the same amount is lost through windows.

The amount of heat lost from the house increases with the number of windows and doors. Up to 60% of heat can be lost through the floor, ceiling, and facade of a poorly insulated home. The facade and windows are the largest surfaces that produce heat. Replacing the windows should be done in the house first, and then the insulation.

When calculating the amount of heat required to heat the room, it is important to account for potential energy losses and either exclude them by using thermal insulation material or add their value.

In terms of how completed masonry houses are arranged, it is important to consider the increased heat losses at the start of the heating season. It is also necessary to consider the date of construction completion:

• from May to June – 14%;
• September – 25%;
• from October to April – 30%.

Hot water supply

The average hot water supply load for the heating season needs to be determined next. The following formula is applied for this purpose:

• a – average daily rate of hot water use (this value is standardized and can be found in the SNiP table in Annex 3);
• N is the number of occupants, employees, students or children (if it is a pre-school) in the building;
• t_c-value of water temperature (measured in fact or taken from averaged reference data);
• T – time interval during which hot water is supplied (if we are talking about hourly water supply);
• Q_(t.n) – heat loss coefficient in the hot water supply system.

Whether it is possible to regulate the loads in the heating unit

A few decades ago, this was an impractical undertaking. Heat load controllers are now a standard feature on practically all contemporary heating boilers used for residential and commercial applications (RTN). These devices prevent surges and overshoots during the operation of the heating units and maintain the power at a predetermined level.

Heat load controllers make it possible to lower the cost of paying for the energy resources used to heat the building.

This is because the equipment has a fixed capacity limit that remains constant throughout operation. This is particularly valid for businesses that are industrial.

The main requirements are patience and the required knowledge. Making a project on your own and calculating the load of the heating units that provide heating, ventilation, and air conditioning in the building is not that difficult.

Self-calculation of heat load for heating: hourly and annual indicators

How can heating expenses be maximized? Only a thorough approach that considers all system parameters as well as regional building and climatic quirks can effectively solve this task. The heating load is the most significant factor in this instance; the system efficiency calculation system includes the hourly and annual value calculations.

Why you need to know this parameter

Distribution of the home’s heat loss

How is the heat load for heating calculated? It establishes the ideal heat energy output for every room in the house as well as the building overall. The boiler, radiators, and pipelines’ capacities are the heating equipment’s variables. The house’s heat losses are also considered.

The heating system’s thermal capacity should ideally be able to offset all heat losses while simultaneously preserving a comfortable temperature. As a result, in order to compute the annual heating load, the following primary factors must be identified:

• Characterization of structural elements of the house. Exterior walls, windows, doors, ventilation system affect the level of heat losses;
• House size. It is logical to assume that the larger the room – the more intensive the heating system should work. An important factor in this is not only the total volume of each room, but also the area of exterior walls and window structures;
• Climate in the region. At relatively small drops in temperature on the street a small amount of energy is needed to compensate for heat losses. Т.е. The maximum hourly heating load depends directly on the degree of temperature drop in a certain period of time and the average annual value for the heating season.

These variables are taken into consideration when preparing the heating system’s ideal thermal mode. In conclusion, calculating the heat load for heating is essential to minimizing energy carrier consumption and maintaining the ideal degree of heating throughout the house’s rooms.

To determine the ideal heating load based on aggregated data, the precise building volume needs to be ascertained. It’s crucial to keep in mind that this methodology was designed for large buildings, meaning there will be a significant computation error.

Selection of calculation methodology

Requirements for residential buildings in terms of hygiene and epidemiology

Understanding the ideal temperature ranges for a residential building is essential before estimating the heating load aggregately or more precisely.

The SanPiN 2.1.2.2645-10 norms must be followed when calculating heating characteristics. The data in the table indicates that each room in the house needs to have its heating system operating at the ideal temperature.

The accuracy of the techniques used to determine the hourly heating load can vary. It is sometimes advised to employ fairly intricate computations because they will produce very little error. Less exact schemes can be employed in heating design if maximizing energy costs is not a top priority.

The hourly heating load calculation needs to account for the street temperature change that occurs every day. Understanding the technical details of the building is essential to increase the calculation’s accuracy.

Simple ways to calculate the heat load

To maximize the heating system’s settings or enhance the home’s thermal insulation qualities, a heat load calculation is required. Following its execution, specific methods for controlling the heating load are chosen. Let’s look at less labor-intensive ways to figure out this heating system parameter.

Dependence of heating power on the area

Table of correction factors for Russia’s various climate zones

The known ratio of the floor area to the necessary heat output can be used for a home with standard room sizes, ceiling heights, and good thermal insulation. In this instance, 10 m² will require the generation of 1 kW of heat. To get the desired outcome, a climate zone-specific correction factor must be applied.

Assume for the moment that the house is situated in the Moscow area. Its entire size is 150 m^. In this instance, the heating load on an hourly basis will be equal:

The primary drawback of this approach is its extreme imprecision. The computation does not account for variations in weather conditions or the building’s characteristics, such as the windows’ and walls’ resistance to heat transfer. As a result, using it in practice is not advised.

An aggregated calculation of the heat load of a building

Results from the combined calculation of the heating load are more precise. When determining the precise characteristics of the building proved to be impossible, it was initially utilized for pre-calculation of this parameter. The following is the general formula for calculating the heating load:

Where q° is the building’s specific heat characteristic. The values for the correction factor (а), outside building volume (Vn), temperature values (Tvn and Tnro), and building volume (m2) should be taken from the corresponding table.

Table of particular building thermal characteristics

Assume for the purposes of this calculation that the maximum hourly heating load in a two-story house with an outer wall volume of 480 m³ (or 160 m²) must be determined. The thermal characteristic in this scenario will be 0.49 W/m³*C. A = 1 is the correction factor (for Moscow region). Within the living space (Tvn), +22 °C is the ideal temperature. The street will have a temperature of -15°C. Let’s apply the following formula to determine the heating load per hour:

The resultant value is less than that of the previous computation. However, it considers crucial elements like the building’s overall volume, indoor and outdoor temperatures. For every room, the same computations can be performed. The best power for each radiator in a given room can be found using the method of calculating the heating load by aggregating indicators. The average temperature values for a given area must be known in order to perform a calculation that is more accurate.

The hourly heat load for heating can be computed using this method. However, the results will not provide a value for the building’s heat losses that is as accurate as possible.

Effective heating and insulation strategies depend on knowing how to compute heat requirements based on building volume. Homeowners can maximize comfort and energy efficiency by making well-informed decisions by taking into account variables like the space’s volume, insulation levels, climate, and intended indoor temperature.

The process of calculating heat requirements entails figuring out how much heat is gained or lost inside a structure. The efficiency of heating systems, air leakage rates, and the thermal conductivity of building materials are just a few of the variables taken into account in this process. Homeowners can choose the right insulation and heating solutions to keep comfortable indoor temperatures while consuming the least amount of energy by precisely evaluating these factors.

Moreover, homeowners can pinpoint areas for energy efficiency improvements by knowing how heat is calculated based on building volume. People can identify areas of heat loss or inefficiency, such as poorly insulated walls or windows, and take corrective action to address these problems by performing a thorough assessment of their home’s heat requirements.

By lowering energy use and greenhouse gas emissions, putting into practice efficient heating and insulation strategies enhances home comfort while also supporting environmental sustainability. Homeowners can reduce their carbon footprint and ultimately save money on energy bills by making investments in energy-efficient heating systems and insulation materials.

To sum up, calculating heat by building volume is an essential part of creating and maintaining a cozy, energy-efficient house. Homeowners can maximize indoor comfort while minimizing energy consumption and environmental impact by taking into account variables like insulation levels, climate, and heating system efficiency.

Video on the topic

Video 8 P 1 Calculation of heat loss for heating

Calculation of building heat load (heat demand). Energy efficiency class of the building.

Calculation of heat loss on a concrete example

Calculation of heating radiators in a private house ❌ ERRORS ❌ One thing on paper, another in real life