Cabinet Regulation No. 280 of 2019 on the Latvian Construction Standard LBN 002-19, Thermotechnics of Building Envelopes

1. The Regulation approves the Latvian Construction Standard LBN 002-19, Thermotechnics of Building Envelopes (hereinafter – the Construction Standard).

2. Cabinet Regulation No. 339 of 30 June 2015, Regulations Regarding the Latvian Construction Standard LBN 002-15, Thermotechnics of Building Envelopes (Latvijas Vēstnesis, 2015, No. 125), is repealed.

3. Building designs which have been drawn up according to specific procedures and coordinated until the day of coming into force of this Regulation need not be remade according to the requirements laid down in the Construction Standard.

4. The Regulation shall come into force on 1 January 2020. Informative Reference to the European Union Directive This Regulation contains legal norms arising from Directive 2010/31/EU of the European Parliament and of the Council of 19 May 2010 on energy performance of buildings. Prime Minister A. K. Kariņš Minister for Economics R. Nemiro Translation © 2020 Valsts valodas centrs (State Language Centre) Approved by Cabinet Regulation No. 280 25 June 2019 Latvian Construction Standard LBN 002-19, Thermotechnics of Building Envelopes I. General Provisions

1. The Construction Standard prescribes: 1.1. the procedures for the energy efficiency design of the structure elements of external building envelopes and their connections for heated buildings to be newly erected, rebuilt, and renewed, and also for new heated premises to be installed in already built buildings the temperature in which during the heating season is maintained at 8 °C and higher; 1.2. the thermotechnical parameters to be used in the calculations during the designing of heating, ventilation, and systems.

2. The purpose of the Construction Standard is to reduce energy consumption in buildings by increasing the efficiency of energy use and to prevent the formation of structural-physical defects in buildings and their structure elements. Energy efficient structure elements limiting carbon dioxide emissions shall be provided for in the construction of buildings.

3. Envelopes or elements of buildings (hereinafter – the structure element) are the external walls, roofs, garret floors, coverings which are in contact with the outdoor air (also over passages), floors on unheated cellars, cold cellars and floor on the ground, external walls of a cellar which are in contact with the outdoor air or ground, windows in the external walls, doors and gates, and also internal walls and other surfaces, if they delimit premises the temperature margin between which is 5 °C and more. Such structure elements and their solutions are energy efficient which provide sufficiently efficient protection of the room from cooling during the winter and from overheating during the summer, ensuring a better thermal comfort indoors. Thermal inertia shall be assessed for the structure elements and the most appropriate combination of load bearing and thermal insulating layers shall be selected.

4. In projects which are co-financed by the European Union, the State, or the local government, the solutions for the designs of rendered façades of external walls and the solutions for the designs of ventilated façades shall be drawn up in accordance with European Technical Approvals issued on the basis on the European Technical Approval Guidelines for External Thermal Insulation Composite Systems ETAG 004.

5. The Construction Standard shall not be applied to the buildings referred to in Section 3, Paragraph two, Clause 2 of the Energy Efficiency Law.

6. A specific micro-climate of high energy intensity shall be ensured for buildings and premises (for example, for freezing rooms, climate chambers), providing for energy efficient structure elements, and the technically and economically most appropriate solution shall be ensured in the application of this Construction Standard, in addition also ensuring high efficiency of energy use for it.

7. Upon performing the thermotechnical calculation and designing of the structure elements, the standards referred to in this Construction Standard shall be applied. Application of an Translation © 2020 Valsts valodas centrs (State Language Centre) 2 alternative methodology for calculation shall be permitted if the result of the technical execution thereof is not worse than that laid down in the standard and it ensures conformity with the essential requirements to be brought forward for the structure laid down in the Construction Law. II. Energy Efficiency Requirements

8. Energy efficiency of the buildings to be newly erected shall conform to the threshold values indicated in Table 1 of Annex to this Construction Standard. Calculation of energy consumption shall be performed in accordance with Cabinet regulations regarding the methodology for calculating the energy efficiency of buildings.

9. Energy efficiency of the buildings to be renewed or rebuilt shall conform to the threshold values indicated in Table 2 of Annex to this Construction Standard. Calculation of energy consumption shall be performed in accordance with Cabinet regulations regarding the methodology for calculating the energy efficiency of buildings.

10. If the average height of the building for premises to be heated is more than 3.5 metres, the minimum permissible level of energy efficiency of the buildings may exceed the indicators referred to in Paragraphs 8 and 9 of this Construction Standard. Taking into account the average height of the building for premises to be heated, the minimum permissible level of energy efficiency of the buildings shall be calculated, using the following formula: h Emin.apr. = Emin × where (1) 3.5 Emin.apr. – minimum permissible level of energy efficiency of the buildings, if the average height of the building for premises to be heated exceeds 3.5 metres (kWh/m2 per year). If the re- calculated minimum permissible level of energy efficiency of the buildings for a building to be newly erected exceeds 90 kWh/m2 per year, the minimum permissible level of energy efficiency of the buildings for a building to be newly erected shall be 90 kWh/m2 per year. If the re- calculated minimum permissible level of energy efficiency of the buildings for renewal or rebuilding exceeds 120 kWh/m2 per year, the minimum permissible level of energy efficiency of the buildings for renewal or rebuilding shall be 120 kWh/m2 per year; h – actual average height of the building for premises to be heated (m); Emin – the minimum permissible level of energy efficiency of the buildings in accordance with Paragraph 9 or 10 of this Construction Standard (kWh/m2 per year).

11. The values Ui and ψj of the calculated heat transmittance coefficients of individual structure elements and linear thermal bridges shall not exceed the maximum values URM and ψRM specified in Table 3 of Annex to this Construction Standard, URM shall be the maximum heat transmittance coefficient W/(m2 × K) of the relevant structure element, whereas ψRM – the maximum heat transmittance coefficient of the relevant linear thermal bridge W/(m × K). The maximum values URM for floors which are in contact with the outdoor air shall be the same as for roofs.

12. If renewal or rebuilding affects less than 25 % of the total surface area of the structure elements of the building, the requirements referred to in Paragraph 9 of this Construction Standard need not be applied. Translation © 2020 Valsts valodas centrs (State Language Centre) 3

13. The temperature in unheated adjacent premises shall be determined in accordance with the standard LVS EN ISO 13789:2017, Thermal performance of buildings – Transmission and ventilation heat transfer coefficients – Calculation method (ISO 13789:2017). III. Calculated Values of Construction Products and Structure Elements

14. The values of the calculated heat transmittance coefficients Ui, ψj, and χk shall be determined for: 14.1. walls, roofs, and floors which are in contact with the outdoor air – in accordance with the standard LVS EN ISO 6946:2017, Building components and building elements – Thermal resistance and thermal transmittance – Calculation methods (ISO 6946:2017); 14.2. floors lacking contact with the outdoor air – in accordance with the standard LVS EN ISO 13370:2017, Thermal performance of buildings – Heat transfer via the ground – Calculation methods (ISO 13370:2017); 14.3. windows and doors – in accordance with the standard LVS EN ISO 10077-1:2017, Thermal performance of windows, doors and shutters – Calculation of thermal transmittance – Part 1: General (ISO 10077-1:2017), and LVS EN ISO 10077-2:2017, Thermal performance of windows, doors and shutters – Calculation of thermal transmittance – Part 2: Numerical method for frames (ISO 10077-2:2017); 14.4. thermal bridges ψj and χk − in accordance with the standard LVS EN ISO 10211:2017, Thermal bridges in building construction – Heat flows and surface temperatures – Detailed calculations, or LVS ISO 14683:2017, Thermal bridges in building construction – Linear thermal transmittance – Simplified methods and default values (ISO 14683:2017). For the determination of the heat transmittance coefficients of thermal bridges ψj and χk such catalogues of thermal bridges may be used in which the values of thermal bridges have been determined, using the calculation conditions of the standard LVS EN ISO 10211:2017, Thermal bridges in building construction – Heat flows and surface temperatures – Detailed calculations (ISO 10211:2017), and the calculation conditions of which correspond to the situation to be designed; 14.5. point thermal bridges χk if they present a risk of condensate – by assessing as an additional attenuation in structures. The necessary calculations and threshold values shall be determined in accordance with LVS EN ISO 13788:2013, Hygrothermal performance of building components and building elements – Internal surface temperature to avoid critical surface humidity and interstitial condensation – Calculation methods (ISO 13788:2012).

15. Thermal bridge ψj (W/mK) is any formation in the construction of a building where the heat transmission of homogeneous envelopes is changed by the following factors: 15.1. the envelope or a part thereof is crossed by materials with different thermal conductivity; 15.2. the thickness of materials changes; 15.3. there is a difference between the external and internal dimensions of the structure element; 15.4. other factors affecting heat losses in local areas.

16. The conformity of the heat transmittance coefficient of a thermal bridge with the values defined in this Construction Standard shall be assessed according to the external dimensions of the structure element. The relative critical surface humidity at sites of the thermal bridge shall be inspected in accordance with the methodology for calculation defined in the standard LVS EN ISO 13788:2013, Hygrothermal performance of building components and building elements – Internal surface temperature to avoid critical surface humidity and interstitial condensation – Calculation methods (ISO 13788:2012), and the permissible threshold values. Translation © 2020 Valsts valodas centrs (State Language Centre) 4 Upon determining the relative critical surface humidity, the calculation shall be performed provided that the temperature of external air is Θe (–5°C).

17. The calculated heat transmittance coefficient Ui for industrially manufactured structure elements in the regulated field shall be certified in a conformity assessment process in accordance with Regulation (EU) No 305/2011 of the European Parliament and of the Council of 9 March 2011 laying down harmonised conditions for the marketing of construction products and repealing Council Directive 89/106/EEC (hereinafter – Regulation No 305/2011).

18. For the construction products the main function of which in the structure element is not thermal insulation and the thermotechnical properties thereof are not certified during the conformity assessment process, the values of the calculated heat transmittance and other thermotechnical characteristics shall be determined in accordance with Table 10 of Annex to this Construction Standard.

19. The measurements of the actual values of the calculated heat transmittance coefficient Ui of the structure elements shall be taken in conformity with the standard LVS EN ISO 8990:2007 L, Thermal insulation – Determination of steady-state thermal transmission properties – Calibrated and guarded hot box. IV. Air Permeability and Energy Efficiency Indicators of Buildings

20. Air permeability of a structure is a structural and physical value characterising the construction quality of the building and ensures a possibility for efficient control of micro- climate in the building and for ensuring of the energy efficiency requirements.

21. Air permeability of the entire building, expressed as an air leak m3/(m2 × h) and measured with the pressure margin 50 Pa (q50), may not exceed the threshold values determined in Paragraph 22 of this Construction Standard.

22. Depending on the method of ventilation of the relevant building, the following threshold values shall be determined for residential houses, homes for the elderly, hospitals, kindergartens, and public buildings: 22.1. for buildings with natural ventilation (airing) – q50 ≤ 3 m3/(m2 × h); 22.2. for buildings with a mechanical ventilation system – q50 ≤ 2 m3/(m2 × h); 22.3. for buildings with a mechanical ventilation system which is equipped with heat recovery (air recuperation) devices – q50 ≤ 1.5 m3/(m2 × h); 22.4. for production buildings – q50 ≤ 4 m3/(m2 × h).

23. The requirements referred to in Paragraph 22 of this Construction Standard shall also be taken into account in relation to the connections and assembly seams of the structure element.

24. Air permeability of buildings shall be determined in accordance with the standard LVS EN 9972:2016, Thermal performance of buildings – Determination of air permeability of buildings – Fan pressurization method (ISO 9972:2016). For the performance of the test, the building shall be prepared according to the Method 2 of the abovementioned standard – by closing all the windows, doors, hatches in the building. V. Water Vapour Permeability of Structure Elements

25. If the structure element, its connections and assembly seams consist of different layers, the total equivalent of air diffusion of water vapour resistance sd of the layers on the warm side Translation © 2020 Valsts valodas centrs (State Language Centre) 5 thereof shall be at least five times greater than the total equivalent of air diffusion of water vapour resistance sd of the layers adjacent to the cold side. The sd values for most commonly utilised membrane materials are determined in Table 4 of Annex to this Construction Standard.

26. The water vapour resistance of construction products shall be determined, using the following formula: where (2) sd – the equivalent of air diffusion of water vapour resistance of construction products (m); µ – the water vapour resistance factor; d – the thickness (m) of the layer of the homogeneous construction product.

27. The structure element shall be designed and constructed in a way that: 27.1. the balance of accumulation of humidity in the structure element within a year is not positive; 27.2. the drying reserve of humidity for the structure elements of the external wall within a year is at least 100 g/m2, for the structure elements of the roof – at least 200 g/m2; 27.3. the maximum possible quantity of absorbed water of layer materials of the structure element is not exceeded; 27.4. the quantity of the water vapour condensate does not exceed 400 g/m2 on surfaces not absorbing humidity in order to preclude trickling of water drops; 27.5. the total quantity of condensate during the annual heating season does not exceed 2 1 kg/m ; 27.6. the quantity of humidity for timber in overall increases by not more than 5 % of their mass, for materials containing wood the quantity of humidity increases by not more than 3 % of their mass; 27.7. upon assessing the long-term safety of humidity damages of the structure element, the assessment includes the quantity of layer humidity of the structure elements, and also the transfer of humidity caused by air permeability of the building in the structure element.

28. The technical solution for the fulfilment of the requirements referred to in Paragraph 25 or 27 of this Construction Standard for the structure element, its connections and assembly seams shall be indicated to the same extent and in the same content as to be able to assess conformity with the requirements laid down.

29. Derogations from the requirements referred to in Paragraph 25 of this Construction Standard shall be permissible if conformity with the requirements referred to in Paragraph 27 of this Construction Standard is ensured.

30. If an air gap between the thermal insulation or wind barrier next to it and the external finish is required to fulfil the requirements referred to in Paragraph 25 or 27 of this Construction Standard, it must be possible to ventilate the thermal insulation. Such thermal insulation is considered ventilated the air separating layer of which is in contact with the outdoor air and the air flow conditions conform to the criteria specified in the standard LVS EN ISO 6946:2017, Building components and building elements – Thermal resistance and thermal transmittance – Calculation methods (ISO 6946:2017). The air separating layer is ventilated, if the following conditions are met: 30.1. the cross-sectional area of ventilation apertures is not smaller than 15 cm2 per each metre of the length of a vertical air separating layer (along the perimeter of the building); 30.2. the cross-sectional area of ventilation apertures is not smaller than 15 cm2 per each square metre of the surface of the envelope for a horizontal air separating layer. Translation © 2020 Valsts valodas centrs (State Language Centre) 6

31. The value sd for glass, ceramic tiles, metals, and metal sheets shall be unlimited. The value 106 m shall be used in the calculations.

32. In respect of hermetic multilayer panels covered on both sides by metal sheets with a thermal insulation layer between them, the requirement referred to in Paragraph 25 of this Construction Standard shall apply to the junctures of the panels which are on the warm and cold sides of the thermal insulation. VI. Thermotechnical Characteristics of Construction Products

33. Upon performing engineering calculations, the information provided by the manufacturer shall be primarily selected as the output data. If such information is not available, it shall be permitted to use studies, the literature of the field, or Annex to this Construction Standard. Upon selecting the data provided by the manufacturer regarding thermal conductivity of materials, it shall be ascertained that it has been checked in accordance with the methodology referred to in Paragraph 36 of this Construction Standard. The declared thermal conductivity λD shall be used for the performance of calculations.

34. The manufacturer shall indicate in the declaration of conformity the declared thermal conductivity λD W/(m × K) for each type of thermal insulation product according to the technical provisions.

35. A class of thermal conductivity shall be determined for all thermal insulating products. The class of thermal insulating product shall be the guaranteed declared thermal conductivity thereof which is expressed in W/(m × K) (Watts per meter and degree) and rounded up to the highest closest class indicator. The manufacturer shall indicate the class of the thermal insulating material according to the technical provisions of the construction product.

36. The declared coefficient of thermal conductivity λD or the declared thermal resistance RD of the thermal insulating material shall be determined in accordance with the standard LVS EN ISO 10456+AC:2013 L, Building materials and products – Hygrothermal properties – Tabulated design values and procedures for determining declared and design thermal values.

37. Conversion of thermal values shall be performed in accordance with the standard LVS EN ISO 10456+AC:2013 L, Building materials and products – Hygrothermal properties – Tabulated design values and procedures for determining declared and design thermal values.

38. Upon determining the calculated heat transmittance value Ui and the thickness of the thermal insulation layer for the structure element, the shrinkage of the bulk thermal insulating material during the lifetime thereof shall be taken into consideration. The extent of shrinkage for glass wool and rock wool shall not be less than 5 %, but for cellulose-based fibres – not less than 20 %.

39. If the measurements of the thermal conductivity are taken according to the harmonised technical provisions for construction products or using matured (aged) materials, the correction factor Dla may be zero.

40. The declared thermal conductivity λD W/(m × K) shall be determined according to the harmonised technical provisions for construction products or using the following formula (if there are no harmonised technical provisions for the relevant thermal insulating material or the Translation © 2020 Valsts valodas centrs (State Language Centre) 7 way of determination of the declared thermal conductivity is not referred to in the harmonised technical provisions): where (3) λ10m – the thermal conductivity value of the thermal insulating material at the average temperature of 10 °C in accordance with Paragraph 28 or 38 of this Construction Standard; Δλs – the correction factor for the evaluated standard deviation in accordance with Paragraph 27 of this Construction Standard; Δλa – the correction factor for ageing.

41. If thermal insulating materials which are manufactured in accordance with the harmonised European standards and which have been labelled with the CE mark, and have a declared product thermal resistance of RD (m2K/W), the thermal conductivity class of such products shall be determined in accordance with formula (4) and the acquired value shall be rounded up to the closest value with accuracy up to 0.001 W/(m × K): where (4) dN – the nominal thickness of the thermal insulating material in accordance with the relevant harmonised European standard. In such case the manufacturer shall indicate the declared thermal conductivity λD or the declared thermal resistance of the construction product RD on the packaging, without indicating the thermal conductivity class with a separate mark.

42. The calculated thermal conductivity λD W/(m × K) of a thermal insulating material, taking into consideration the envelopes in actual working conditions, shall be determined in accordance with the standard LVS EN ISO 6946:2017, Building components and building elements – Thermal resistance and thermal transmittance – Calculation methods (ISO 6946:2017), or by using formula (5), adding the adjustment-for-working-conditions coefficient Δλw to the result obtained in accordance with Table 4 of Annex to this Construction Standard unless specified otherwise in the harmonised standard for a construction product: (5)

43. The calculated thermal conductivity of the thermal insulating material for the structure element to be indicated in the documentation of the construction intention shall be determined in accordance with Paragraph 42 of this Construction Standard.

44. The values Δλw of the adjustment coefficient for the thermal insulating materials most frequently used in the structure elements are specified in Table 5 of Annex to this Construction Standard.

45. The values of the correction coefficient Δλwspecified in Table 6 of Annex to this Construction Standard shall apply to thermal insulating materials which are used on the ground, in the external walls of a cellar, under the floor on the ground or outside horizontally as a protection measure against frost heave of the soil. If the density of the thermal insulating material conforms to the range indicated in the abovementioned table, the values of the correction coefficient Δλw shall be determined by means of a linear interpolation. If the density of the thermal insulating material does not conform to the range referred to in the table, the use thereof in such manner is not permitted. Translation © 2020 Valsts valodas centrs (State Language Centre) 8

46. The values of the correction coefficient Δλw for inverted roof constructions for the thermal insulation of which extruded expanded polystyrene (XPS) or grooved sheets thereof covered with a straining cloth have been applied shall be specified in Table 7 of Annex to this Construction Standard. An inverted roof shall be such a roof in which the thermal insulation layer is laid over the waterproofing layer.

47. The calculated thermal conductivity shall be used upon determining the value of the calculated thermal conductivity coefficient Ui of the structure element.

48. The calculated thermal conductivity λd for construction products to be used in a regulated field the conformity of which has not been certified as for thermal insulating materials in accordance with Regulation No 305/2011 shall be determined in accordance with Table 10 of Annex to this Construction Standard. VII. Thermal Inertia of Structure Elements

49. Thermal inertia shall depend on thermal mass of the structures of a building. Thermal mass is a function from the density of the material (ρ, kg/m3) and the specific heat capacity cp (kJ/(kgK)) and is the indicator of heat resistance.

50. The thermal inertia of the structure element shall be calculated in accordance with the standard LVS EN ISO 52016-1:2017, Energy performance of buildings – Energy needs for heating and cooling, internal temperatures and sensible and latent heat loads – Part 1: Calculation procedures (ISO 52016-1:2017).

51. The dimensions λ, ρ, and c for some construction products are indicated in accordance with Paragraph 39 of this Construction Standard and also are indicated in Tables 9 and 10 of Annex to this Construction Standard. The humidity of some construction products for the calculations of thermal inertia in percentage is specified in Table 7 of Annex to this Construction Standard. For thermal insulating materials the calculated thermal conductivity λ d of which is determined in accordance with this Construction Standard, in calculations of inertia = λ. d. Minister for Economics R. Nemiro Translation © 2020 Valsts valodas centrs (State Language Centre) 9 Annex to Latvian Construction Standard LBN 002-19, Thermotechnics of Building Envelopes (approved by Cabinet Regulation No. 280 of 25 June 2019) Indicators of Thermotechnics of Building Envelopes and Their Values Table 1 Minimum Permissible Level of Energy Efficiency of Buildings for Newly Erected Buildings1 Minimum permissible level of energy efficiency of buildings, energy efficiency assessment for heating of newly erected buildings for non-residential buildings (the types of buildings referred to for residential buildings in Sub-paragraphs 6.1.3, 6.1.4, 6.1.5, 6.1.6, 6.1.7, 6.1.8, and 6.1.9 Acceptance period of the Regulation2) of the documentation of buildings which No. are in the the construction intention of the ownership of the building State or local one-apartment multi- government and in other non- or two- apartment the possession of residential apartment buildings the authorities and buildings buildings where the State or local government authorities are located

1. Until ≤ 70 kWh/m2 ≤ 80 kWh/m2 ≤ 100 kWh/m2 per ≤ 100 kWh/m2 31 December 2016 per year per year year per year

2. From ≤ 60 kWh/m 2 ≤ 70 kWh/m ≤ 90 kWh/m per ≤ 90 kWh/m2 2 2 1 January 2017 to per year per year year per year 31 December 2017

3. From ≤ 60 kWh/m2 ≤ 70 kWh/m2 ≤ 65 kWh/m2 per ≤ 90 kWh/m2 1 January 2018 to per year per year year per year 31 December 2018

4. From ≤ 50 kWh/m2 ≤ 60 kWh/m2 nearly zero-energy ≤ 65 kWh/m2 1 January 2019 to per year per year building per year 31 December 2020

5. From nearly zero- nearly zero- nearly zero-energy nearly zero- 1 January 2021 energy building energy building energy building building Translation © 2020 Valsts valodas centrs (State Language Centre) 10 Notes. 1 The minimum permissible level (class) of energy efficiency of buildings for the buildings to be newly erected need not be applied if application of the relevant requirements is either technically or functionally impossible and benefit analysis on the useful lifetime of the relevant building indicates to losses. 2 Cabinet Regulation No. 383 of 9 July 2013, Regulations Regarding Energy Certification of Buildings. Table 2 Minimum Permissible Level of Energy Efficiency of Buildings for Renewal and Rebuilding of Buildings The minimum permissible level of energy efficiency of buildings, assessment of energy efficiency for heating for the buildings to be renewed and rebuilt for non-residential buildings (the types of buildings referred to for residential buildings in Sub-paragraphs 6.1.3, 6.1.4, 6.1.5, 6.1.6, 6.1.7, 6.1.8, and 6.1.9 Acceptance period of the Regulation1) of the buildings which documentation of are in the No. the construction ownership of the intention of the State or local building one-apartment government and multi- other non- or two- in the possession apartment residential apartment of the authorities buildings buildings buildings and where the State or local government authorities are located

1. From ≤ 90 kWh/m 2 ≤ 100 kWh/m ≤ 110 kWh/m2 2 ≤ 110 kWh/m2 21 November 2015 per year per year per year per year to 31 December 2020

2. From ≤ 80 kWh/m2 ≤ 90 kWh/m2 ≤ 90 kWh/m2 per ≤ 100 kWh/m2 1 January 2021 per year per year year per year Note. 1 Cabinet Regulation No. 383 of 9 July 2013, Regulations Regarding Energy Certification of Buildings. Translation © 2020 Valsts valodas centrs (State Language Centre) 11 Table 3 Maximum Permissible Levels of the Heat Transmittance Coefficients URM W/(m2 × K) and ψRM W/(m × K) of the Structure Element and the Linear Thermal Bridge Residential houses, homes Non-residential Production for the elderly, buildings buildings hospitals, and No. Structure kindergartens Value of Value of URM, Value of URM, URM, W/(m2K) W/(m2K) W/(m2K)

1. Floor1: 1.1. floors and walls in contact with the 0.2 0.25 0.35 ground 1.2. floor to a non-heated basement or 0.3 0.35 0.40 floor with a ventilated cellar

2. External walls: 2.1. external walls 0.23 0.25 0.30 2.2. walls in traditional log buildings 0.65 0.65 0.65 without building of a thermal insulation layer into the wall

3. Roofs and coverings which are in 0.20 0.23 0.25 contact with outdoor air

4. External doors and gates 1.80 2.00 2.20

5. Windows and balcony doors2 1.10 1.10 1.30

6. Thermal bridges, ψRM 0.20 0.20 0.35 Notes. 1 In all cases the calculation in accordance with the standard LVS EN ISO 13370:2017, Thermal performance of buildings – Heat transfer via the ground – Calculation methods (ISO 13370:2017). 2 The indicated value of U is the value of calculation in accordance with Table F3 of Annex F to the standard LVS EN ISO 10077-1:2017, Thermal performance of windows, doors and shutters – Calculation of thermal transmittance – Part 1: General (ISO 10077-1:2017). A standard window with the part of the frame in the amount of 30 % from the total area shall be viewed. Table 4 Equivalent of Air Diffusion of Water Vapour Resistance sd for Membrane Materials Equivalent of air diffusion of water No. Product or material vapour resistance sd (m)

1. Polyethylene film 0.15 mm 50

2. Polyethylene film 0.2 mm 75

3. Polyethylene film 0.25 mm 100 Translation © 2020 Valsts valodas centrs (State Language Centre) 12

4. Polyester film 0.2 mm 50

5. Polyvinyl chloride (PVC) film 30

6. Aluminium foil 0.05 mm 1500

7. Polyethylene film (squeeze-clamped) 8 0.15 mm

8. Polyethylene film (squeeze-clamped) 12 0.20 mm

9. Glassine 1 mm 2

10. Prepared roofing paper 15

11. Aluminium-based paper 0.4 mm 10

12. Air pervious (breathing) windproof 0.2 membrane

13. Acrylic paint (0.1-0.2 mm layer) 1

14. Latex paint (0.1 mm layer) 0.3

15. Alkyd paint (0.1 mm layer) 4

16. Polyurethane paint (0.03 mm layer) 4

17. Silicate paint (0.1 mm layer) 0.2

18. Vinyl wallpaper 2 Notes.

1. The warm side sd of the structure element is the value of such layers which are located before the layer of thermal insulation up to the first air layer to be ventilated (internal layer).

2. The cold side sd of the structure element is the value of such layers which are located after the layer of thermal insulation (inclusive) up to the first air layer to be ventilated (external layer).

3. For masonry and massive structure elements the total equivalent of air diffusion of water vapour resistance sd,i of the layers on the warm side thereof shall be not less than 2 m.

4. For structure elements of light-weight framework structures the total equivalent of air diffusion of water vapour resistance sd,i of the layers on the warm side thereof shall be not less than 5 m.

5. For structure elements of non-ventilated roofs with a non-ventilated structure of the roof covering the equivalent of air diffusion of water vapour resistance sd,i of the layers on the warm side thereof shall be not less than 50 m. Table 5 Adjustment Coefficient Δλw W/(m × K) for Thermal Insulating Materials and Products to be Used in the Structure Elements Depending on the Working Conditions of Thermal Insulation Working conditions of thermal insulation Name of the thermal insulating material or product, Non-ventilated No. Ventilated specific resistance or density of air permeability structure structure element element Δλw (W/mK) Δλw (W/mK)

1. Mineral wool (rock wool, glass wool) products with 0.006 0.008 –2 Ra ≤ 6 kPa × s × m Translation © 2020 Valsts valodas centrs (State Language Centre) 13

2. Mineral wool (rock wool, glass wool) products with 0.001 0.002 Ra > 6 kPa × s × m–2

3. Loose-fill mineral wool with Ra ≤ 6 kPa × s × m–2 0.008 may not be used

4. Loose-fill pulp fibre (ecowool) 0.008 may not be r > 25 kg/m3 (Ra > 6 kPa × s × m–2) used

5. Hydraulically entangled pulp fibre 0.008 0.02 ρ = 35–75 kg/m3 (Ra > 6 kPa × s × m–2)

6. Extruded polystyrene (XPS) plates 0.001 0.002

7. Phenol and carbamide-formaldehyde plastic foam 0.02 0.03 plates

8. Aerated concrete ρ ≤ 400 kg/m3 0.015 0.02

9. Aerated concrete 400 < ρ ≤ 600 kg/m3 0.03 0.04

10. Aerated concrete ρ > 600 kg/m3 0.07 0.08

11. Reed plates ρ = 200 kg/m3 0.035 may not be used

12. Perchlor vinyl plastic foam sheets 0.012 0.015

13. Expanded polystyrene (EPS) plates 0.003 0.004

14. Foam gypsum ρ = 500 kg/m3 0.07 0.08

15. Foam polyurethane and foam polyurethane plates 0.012 0.015

16. Straw plates (with liquid glass binder) ρ = 350 kg/m3 0.045 may not be used

17. Fibrolite plates 0.002 0.003

18. Arbolite plates 0.015 0.017

19. Keramzite concrete 400 < ρ ≤ 600 kg/m3 0.01 0.02

20. Keramzite concrete 600 < ρ ≤ 800 kg/m3 0.025 0.045

21. Keramzite concrete 800 < ρ ≤ 1000 kg/m3 0.05 0.07

22. Peat plates 200 < ρ ≤ 300 kg/m3 0.015 0.02

23. Crude fibre and particle plates ρ = 200 kg/m3 0.015 may not be used

24. Crude fibre and particle plates ρ = 1000 kg/m3 0.11 may not be used

25. Foam glass ρ = 200 kg/m3 0.02 0.025

26. Foam glass ρ = 400 kg/m3 0.035 0.04 Note. In ventilated air separating layers the thermal insulating products shall be protected from outside by a wind barrier or the surface thereof shall be provided with a thermal insulating product against enforced convection effects upon the thermal conductivity of the thermal insulating material. This condition does not apply to cold attics in which the speed of the airflow above the thermal insulating materials does not exceed 0.5 m/s. Translation © 2020 Valsts valodas centrs (State Language Centre) 14 Table 6 Adjustment Coefficient Δλw W/(m × K) under Increased Humidity Conditions for Various Density r (kg/m3) Thermal Insulating Materials which are in Direct Contact with the Soil For unilateral For bilateral (mutual) contact with the contact with the No. Insulating product ground ground Δλw Δλw

1. Aerated concrete ρ = 300–600 kg/m3 0.02-0.04 may not be used

2. Keramzite concrete ρ = 400–600 kg/m3 0.01-0.02 may not be used

3. Keramzite fill ρ = 200–400 kg/m3 0.05-0.06 0.06-0.07

4. Mineral wool ρ ≥ 100 kg/m3 0.005 0.01

5. Expanded polystyrene (EPS) ρ ≥ 30 kg/m3 0.01 0.02

6. Extruded polystyrene (XPS) ρ ≥ 25 kg/m3 0.002 0.004 Table 7 Adjustment Coefficient Δλw W/(m × K) under Increased Humidity Conditions for Extruded Polystyrene (XPS) Plates the Density of which ρ = 25–40 kg/m3and which are in an Inverted Roof No. Type of a construction Δλw (W/mK)

1. Open ventilated surface: 1.1. one extruded polystyrene (XPS) layer and gravel dike 0.001 1.2. two extruded polystyrene (XPS) layers and gravel dike 0.003

2. Closed unventilated surface: 2.1. roof terraces with extruded polystyrene (XPS) thermal insulation and 0.008 covered with humus 2.2. extruded polystyrene insulation (XPS) under pavement 0.008 2.3. extruded polystyrene (XPS) insulation under concrete surface in car parks 0.008 Table 8 Weight Humidity w of Construction Products in Percentage for the Calculation of Thermal Inertia No. Material Weight humidity w (%)

1. Expanded polystyrene (EPS) 10

2. Foam polyurethane 5

3. Reinforced concrete 3

4. Keramzite concrete 10

5. Slag concrete 8

6. Aerated concrete 12

7. Mortar 4 Translation © 2020 Valsts valodas centrs (State Language Centre) 15

8. Brick wall 4

9. Conifers 20

10. Oak 15

11. Particle boards 12

12. Sand 2

13. Keramzite 3

14. Slag 4 Table 9 Thermotechnical Characteristics of Construction Products and Calculation Values Humidity at a Humidity at relative air a relative air Water Specific humidity of humidity of Humidity Density vapour heat 50 % and at a 80 % and at a conversion No. Material ρo resistance capacity temperature temperature coefficient (kg/m3) factor c of 23 °C of 23 °C fu µ J/(kg × K) u23,50 u23,80 (kg/kg) (kg/kg)

1. Expanded 10-50 0.01 0.01 0.1 60 1450 polystyrene (EPS)

2. Extruded 20-65 0.001 0.0015 0.1 150 1450 polystyrene (XPS)

3. Foam 28-55 0.02 0.03 0.3 60 1400 polyurethane boards

4. Phenol plastic 20-50 0.02 0.03 0.2 50 1400 foam

5. Glass wool 10-120 0.004 0.005 2.5 1 1030

6. Rock wool 15-200 0.004 0.005 2.5 1 1030

7. Foam glass 100- 0 0 0 106 1000 150

8. Perlite boards 140- 0.02 0.03 0.8 5 900 240

9. Cork plates 90-160 0.05 0.07 1.0 10 1560

10. Phenol and 10-30 0.1 0.15 0.7 2 1400 carbamide- formaldehyde plastic foam

11. Sprayed 10-30 0.02 0.03 0.3 60 1400 polyurethane foam

12. Wood wool with 30-150 0.12 0.2 1.0 5 1600 liquid glass

13. Wood wool with 250- 0.06 0.1 1.0 5 1470 cement 450 Translation © 2020 Valsts valodas centrs (State Language Centre) 16

14. Fibre board (soft) 150- 0.1 0.16 1.5 10 1400 250

15. Loose-fill glass 15-60 0.004 0.005 2.5 1 1030 wool

16. Loose-fill rock 20-60 0.004 0.005 2.5 1 1030 wool

17. Loose-fill 20-60 0.11 0.18 0.5 2 1600 cellulose-based fibre (Eco Wool)

18. Loose-fill foam 30-150 0.01 0.02 3 2 900 perlite

19. Loose-fill 200- 0 0.001 4 2 1080 keramzite 400

20. Loose-fill 10-30 0.01 0.02 0.2 2 1400 expanded polystyrene (particulate matters)

21. Clay bricks 1000- 0.006 0.01 10 16 1000 2400

22. Calcium silicate 1000- 0.006 0.012 4 20 1000 2000

23. Pumice concrete 500- 0.025 0.045 2.6 50 1000 1300

24. Concrete with 1600- 0.011 0.018 6.4 150 1000 airtight filling 2400

25. Industrially 1600- 0.011 0.018 6.4 150 1000 produced stone 2400

26. Concrete filled 600- 0.06 0.10 3 120 1000 with expanded 1200 polystyrene

27. Keramzite 400- 0.02 0.03 2.6 6 1000 concrete 700 Table 10 Calculation Values of Thermotechnical Characteristics of Construction Products Water Density Thermal Specific heat Group of vapour No. Material ρo conductivity λd capacity c materials resistance (kg/m3) W/(m × K) J/(kg × K) factor µ

1. Metals aluminium 2700 220 890 ∞ (106) duralumin 2800 160 880 ∞ (106) brass 8400 120 380 ∞ (106) bronze 8700 65 380 ∞ (106) copper 8900 370 380 ∞ (106) Translation © 2020 Valsts valodas centrs (State Language Centre) 17 low-carbon steel 7900 75 450 ∞ (106) pig iron 7500 50 450 ∞ (106) alloy steel 7800 50 450 ∞ (106) reinforcing steel 7850 58 480 ∞ (106) stainless steel 7900 17 460 ∞ (106) lead 11300 35 130 ∞ (106) zinc 7100 110 380 ∞ (106)

2. Wood and homogeneous 150 0.07 1610 40 materials on wood 300 0.10 1610 40 the basis 500 0.13 1610 40 thereof 1000 0.24 1610 40 plywood 150 0.07 1610 400 300 0.10 1610 400 500 0.13 1610 400 1000 0.24 1610 400 particle board 300 0.10 1700 50 500 0.14 1700 50 700 0.18 1700 50 particle board with 1200 0.23 1500 50 concrete binder hardboard 400 0.09 1700 10 600 0.15 1700 10 800 0.18 1700 10 pressed 1000 0.23 2300 10 paperboard paper 1000 0.27 2300 – corrugated 650 0.18 2300 7 cardboard

3. Gypsum gypsum 600 0.18 1000 10 1500 0.54 1000 10 gypsum 900 0.25 1050 10 paperboard

4. Mortar normal masonry 1800 0.9 1100 10 mortar, mixed on the building site

5. Concrete cast concrete with 1600 0.7 1080 100 fragments or 2400 2.0 1060 130 shingles reinforced 2500 2.0 840 100 concrete clay with straw 800 0.4 1260 – sawdust concrete 800 0.3 1460 2 1000 0.4 1520 2.5 slag concrete 1400 0.93 840 30 Translation © 2020 Valsts valodas centrs (State Language Centre) 18

6. Stones basalt 2700- 3.5 860 10000 3000 granite 2500- 2.8 800 10000 3000 sandstone 2000- 2.0 860 40 2500 limestone 2000- 2.5 870 200 2500 dolomite 2400 2.2 880 10

7. Soils clay 1200- 1.5 1670-2500 – 1800 gravel and sand 1700- 2.0 910-1180 – 2200

8. Water, ice, water (10 °C) 1000 0.6 4187 – snow ice (0 °C) 900 2.2 2000 – snow (new) 100 0.06 2000 – < 30 mm snow (new) 200 0.12 2000 – 30–70 mm snow (slightly 300 0.23 2000 – sunk) 70-100 mm snow 500 0.70 2000 – (significantly sunk) > 200 mm

9. Plastering cement-perlite 1000 0.3 840 4 cement-slag 1400 0.7 840 6 polystyrene (XPS) gypsum-perlite 600 0.25 840 4 gypsum 1300 0.65 840 6 limestone-sand- 1700 0.9 840 6 cement limestone-sand 1600 0.8 840 5 polymer cement 1800 1.0 840 10

10. Glass quartz glass – 1.4 700 ∞ (106) glass mosaic 2000 1.2 1000 ∞ (106) simple window 2500 1.0 720 ∞ (106) glass

11. Gas air 1.23 0.025 1008 1 argon 1.7 0.017 519 1 krypton 3.56 0.009 245 1 xenon 5.90 0.0055 160 1 carbon dioxide 1.95 0.014 820 1 (CO2) 12. acrylic 1050 0.20 – 10000 polycarbonate 1200 0.21 1200 5000 Translation © 2020 Valsts valodas centrs (State Language Centre) 19 Plastic, hard PTFE 2200 0.23 1000 10000 (without hard polyvinyl 1390 0.18 900 50000 pores) chloride (PVC) polyvinyl chloride 1200 0.14 1000 50000 (PVC) with 40 % softener polyethylene, high 980 0.40 1800 100000 density (HD) polyethylene, low 920 0.32 2100 100000 density (LD) polystyrene 1050 0.18 1300 100000 polyacetal 1410 0.30 1400 100000 phenol- 1400- 0.3-0.7 1200 – formaldehyde 1800 polypropylene 910 0.22 1700 10000 EPDM 1150 0.20 1000 6000 PMMA (acrylate) 1180 0.18 1500 – polyurethane 1200 0.25 1800 6000 polyamide 1130 0.25 1700 – epoxy resins 1200 0.23 800-1400 10000

13. Silicones pure silicone 1000- 0.25-0.35 1000 5000 1050 filled silicone 1300- 0.35-0.5 1000 5000 1450

14. Rubber polysobutylen 920 0.13 1130 – butyl (hot 1200 0.24 – 200000 smelted) neoprene 1240 0.23 2140 porous rubber 60-80 0.04 1500 7000

15. Glazing solid butyl rubber – 0.24 – 200000 distance polyester resins 1.4 0.19 1200 200000 pieces Kiesel gel – 0.13 – – silicone foam – 0.12 – –

16. Materials nylon 1140 0.23 1700 – for tamping urethane (liquid) – 0.3 – – silicone foam – 0.12 – – elastic vinyl – 0.12 – – flexible porous 70 0.05 – – rubber polyethylene foam 36 0.06 2300 100

17. Roofings asphalt 2100- 0.7 1500 50000 2300 bitumen 1000 0.13 1000 50000 Translation © 2020 Valsts valodas centrs (State Language Centre) 20 prepared roofing 1100 0.23 1000 50000 paper clay roof tiles 1900 0.9 900 10 concrete roof tiles 2100 1.4 1000 50

18. Floor linoleum 1300 0.17 1400 5000 coverage cork linoleum 500-700 0.10 1300 1500 carpet floors – 0.07 – 5 plastics and rubber 1200- 0.17-0.27 1400 10000 1700

19. Solid brick ceramic bricks 1800 0.81 880 10 wall sand-cement grout silicate bricks 1800 0.87 880 10 sand-cement grout

20. Hollow ceramic bricks 1600 0.64 880 155 3 brick wall 1400 kg/m gross sand-cement grout ceramic bricks 1400 0.58 880 15 3 1300 kg/m gross sand-cement grout ceramic bricks 1200 0.52 880 15 1000 kg/m3gross sand-cement grout silicate bricks 1500 0.81 880 15 sand-cement grout silicate bricks 1400 0.76 880 15 sand-cement grout Minister for Economics R. Nemiro Translation © 2020 Valsts valodas centrs (State Language Centre) 21