EN 1264-3:2009
(Main)Water based surface embedded heating and cooling systems - Part 3: Dimensioning
Water based surface embedded heating and cooling systems - Part 3: Dimensioning
This European Standard applies to heating and cooling systems embedded into the enclosure surfaces of the room to be heated or to be cooled.
This document deals with the use in practical engineering of the results coming from part 2 and 5 and is applicable to floor-, ceiling- and wall heating systems, as well floor-, ceiling- and wall cooling systems.
For heating systems, physiological limitations are taken into account when specifying the surface temperatures. In the case of floor heating systems the limitations are realised by a design based on the characteristic curves and limit curves determined in accordance with part 2 of this Standard.
For cooling systems, only a limitation with respect to the dew point is taken into account. In predominating practice, this means that physiological limitations are included as well.
Raumflächenintegrierte Heiz- und Kühlsysteme mit Wasserdurchströmung - Teil 3: Auslegung
Diese Europäische Norm gilt für raumflächenintegrierte Heiz- und Kühlsysteme, welche in die Raumumschließungsflächen
des zu heizenden oder des zu kühlenden Raumes integriert sind.
Dieses Dokument behandelt die Anwendung der Ergebnisse aus den Teilen 2 und 5 im praktischen
Ingenieurswesen und gilt sowohl für Fußboden-, Decken- und Wandheizsysteme als auch für Fußboden-,
Decken- und Wandkühlsysteme.
Im Falle von Heizsystemen werden die physiologisch bedingten Grenzen bei der Festlegung der Oberflächentemperaturen
berücksichtigt. Im Falle von Fußbodenheizsystemen wird den Grenzen durch eine Auslegung
Rechnung getragen, die auf den nach Teil 2 dieser Norm ermittelten Kennlinien und Grenzkurven basiert.
Im Falle von Kühlsystemen wird eine Leistungsbegrenzung ausschließlich durch den Taupunkt berücksichtigt.
In der Praxis bedeutet dies in der Regel, dass dadurch zugleich die physiologisch bedingten Grenzen
einbezogen werden.
Systèmes de surfaces chauffantes et rafraîchissantes hydrauliques intégrées - Partie 3 : Dimensionnement
La présente Norme européenne s'applique aux systèmes de surfaces chauffantes et rafraîchissantes
intégrées dans le sol, les plafonds et les murs d'une pièce devant être chauffée ou rafraîchie.
Le présent document traite de l'utilisation, dans l'ingénierie pratique, des résultats émanant des parties 2 et 5
et s’applique aux systèmes de chauffage par le sol, les plafonds et les murs, ainsi qu’aux systèmes de
rafraîchissement dans les sols, les plafonds et les murs.
Pour les systèmes de chauffage, les limites physiologiques sont prises en compte lors de la définition des
températures de surface. Dans le cas de systèmes de chauffage par le sol, les limites sont calculées à l'aide
de courbes caractéristiques et de courbes limites déterminées conformément à la partie 2 de la présente
Norme européenne.
Pour les systèmes de rafraîchissement, seule une limite par rapport au point de rosée est prise en compte.
Dans la majorité des cas, cela signifie que les limites physiologiques sont également comprises.
Ploskovni sistemi za gretje in hlajenje z vodo - 3. del: Dimenzioniranje
General Information
- Status
- Withdrawn
- Publication Date
- 01-Sep-2009
- Withdrawal Date
- 20-Jan-2026
- Technical Committee
- CEN/TC 130 - Space heating appliances without integral heat sources
- Drafting Committee
- CEN/TC 130/WG 9 - Floor heating - Systems and components
- Current Stage
- 9960 - Withdrawal effective - Withdrawal
- Start Date
- 19-May-2021
- Completion Date
- 28-Jan-2026
Relations
- Effective Date
- 08-Jun-2022
- Effective Date
- 05-Sep-2009
- Replaced By
EN 1264-3:2021 - Water based surface embedded heating and cooling systems - Part 3: Dimensioning - Effective Date
- 02-May-2018
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Refers
EN 1264-4:2021 - Water based surface embedded heating and cooling systems - Part 4: Installation - Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
Get Certified
Connect with accredited certification bodies for this standard

ICC Evaluation Service
Nonprofit organization that performs technical evaluations of building products.

Aboma Certification B.V.
Specialized in construction, metal, and transport sectors.
BBA (British Board of Agrément)
UK construction product certification.
Sponsored listings
Frequently Asked Questions
EN 1264-3:2009 is a standard published by the European Committee for Standardization (CEN). Its full title is "Water based surface embedded heating and cooling systems - Part 3: Dimensioning". This standard covers: This European Standard applies to heating and cooling systems embedded into the enclosure surfaces of the room to be heated or to be cooled. This document deals with the use in practical engineering of the results coming from part 2 and 5 and is applicable to floor-, ceiling- and wall heating systems, as well floor-, ceiling- and wall cooling systems. For heating systems, physiological limitations are taken into account when specifying the surface temperatures. In the case of floor heating systems the limitations are realised by a design based on the characteristic curves and limit curves determined in accordance with part 2 of this Standard. For cooling systems, only a limitation with respect to the dew point is taken into account. In predominating practice, this means that physiological limitations are included as well.
This European Standard applies to heating and cooling systems embedded into the enclosure surfaces of the room to be heated or to be cooled. This document deals with the use in practical engineering of the results coming from part 2 and 5 and is applicable to floor-, ceiling- and wall heating systems, as well floor-, ceiling- and wall cooling systems. For heating systems, physiological limitations are taken into account when specifying the surface temperatures. In the case of floor heating systems the limitations are realised by a design based on the characteristic curves and limit curves determined in accordance with part 2 of this Standard. For cooling systems, only a limitation with respect to the dew point is taken into account. In predominating practice, this means that physiological limitations are included as well.
EN 1264-3:2009 is classified under the following ICS (International Classification for Standards) categories: 91.140.10 - Central heating systems. The ICS classification helps identify the subject area and facilitates finding related standards.
EN 1264-3:2009 has the following relationships with other standards: It is inter standard links to EN 15377-2:2008, EN 1264-3:1997, EN 1264-3:2021, EN 16798-13:2017, EN 16798-9:2017, EN 1264-1:1997, CEN/TR 16798-14:2017, EN 1264-4:2021, EN 12831-1:2017, EN 1264-5:2021, EN ISO 7730:2025, EN 1264-2:2021, EN 1264-1:2011, EN 1264-2:2008+A1:2012. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
EN 1264-3:2009 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Ploskovni sistemi za gretje in hlajenje z vodo - 3. del: DimenzioniranjeRaumflächenintegrierte Heiz- und Kühlsysteme mit Wasserdurchströmung - Teil 3: AuslegungSystèmes de surfaces chauffantes et rafraîchissantes hydrauliques intégrées - Partie 3 : DimensionnementWater based surface embedded heating and cooling systems - Part 3: Dimensioning91.140.10Sistemi centralnega ogrevanjaCentral heating systemsICS:Ta slovenski standard je istoveten z:EN 1264-3:2009SIST EN 1264-3:2009en,de01-december-2009SIST EN 1264-3:2009SLOVENSKI
STANDARDSIST EN 15377-2:2008SIST EN 1264-3:19971DGRPHãþD
EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 1264-3September 2009ICS 91.140.10Supersedes EN 1264-3:1997, EN 15377-2:2008
English VersionWater based surface embedded heating and cooling systems -Part 3: DimensioningSystèmes de surfaces chauffantes et rafraîchissanteshydrauliques intégrées - Partie 3 : DimensionnementRaumflächenintegrierte Heiz- und Kühlsysteme mitWasserdurchströmung - Teil 3: AuslegungThis European Standard was approved by CEN on 1 August 2009.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre:
Avenue Marnix 17,
B-1000 Brussels© 2009 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 1264-3:2009: ESIST EN 1264-3:2009
Figures . 16 SIST EN 1264-3:2009
1 Scope This European Standard applies to heating and cooling systems embedded into the enclosure surfaces of the room to be heated or to be cooled. This document deals with the use in practical engineering of the results coming from part 2 and 5 and is applicable to floor-, ceiling- and wall heating systems, as well floor-, ceiling- and wall cooling systems. For heating systems, physiological limitations are taken into account when specifying the surface temperatures. In the case of floor heating systems the limitations are realised by a design based on the characteristic curves and limit curves determined in accordance with part 2 of this Standard. For cooling systems, only a limitation with respect to the dew point is taken into account. In predominating practice, this means that physiological limitations are included as well. 2 Normative References The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 1264-1:1997, Water based surface embedded heating and cooling systems - Part 1: Definitions and symbols EN 1264-2, Water based surface embedded heating and cooling systems - Part 2: Floor heating: Prove methods for the determination of the thermal output using calculation and test methods EN 1264-4, Water based surface embedded heating and cooling systems - Part 4: Installation EN 1264-5, Water based surface embedded heating and cooling systems — Part 5: Heating and cooling surfaces embedded in floors, ceilings and walls — Determination of the thermal output EN 12831, Heating systems in buildings — Method for calculation of the design heat load EN 15243, Ventilation for buildings — Calculation of room temperatures and of load and energy for buildings with room conditioning systems EN ISO 7730, Ergonomics of the thermal environment - Analytical determination and interpretation of thermal comfort using calculation of the PMV and PPD indices and local thermal comfort criteria (ISO 7730:2005) 3 Terms, definitions and symbols For the purposes of this document, the definitions and symbols given in EN 1264-1:1997 apply. SIST EN 1264-3:2009
iRiVRVHlnϑ−ϑϑ−ϑϑ−ϑ=ϑ∆
(1) 4.1.1.2 Characteristic curve The characteristic curve describes the relationship between the specific thermal output q of a system and the required temperature difference between heating water and room ∆ϑH. For a simplification, the specific thermal output is taken directly proportional to the temperature difference:
q = KH ⋅ ∆ϑH (2) where the gradient is KH = B )(iimia, calculated in accordance with clause 6 of part 2 of this Standard, or the gradient KH is experimentally determined in accordance with clause 9 of part 2 of this European Standard. 4.1.1.3 Field of characteristic curves The field of characteristic curves of a floor heating system with a specific pipe spacing T shall at least contain the characteristic curves for values of the thermal resistance Rλ, B = 0, Rλ, B = 0,05, Rλ, B = 0,10 and Rλ, B = 0,15 (m2 K)/W in accordance with part 2 of this European Standard (see Figure A.1). Values of Rλ, B > 0,15 (m2 K)/W shall not be used if possible. 4.1.1.4 Limit curves The limit curves in the field of characteristic curves describe in accordance with part 2 of this European Standard the relationship between the specific thermal output q and the temperature difference ∆ϑH between the heating water and the room in the case where the physiologically agreed limit values of surface temperatures ϑF,max = 29 °C (occupied area) or ϑF,max = 35 °C (peripheral area) are reached1. For bathrooms (ϑi = 24 °C) the limit curve for (ϑF,max - ϑi) = 9 K also applies. For design purposes, i.e. the determination of design values of the specific thermal output and the associated temperature difference between heating water and room, the limit curves are valid for the temperature drop σ of the heating water in a range of 0 K < σ ≤ 5 K. The limit curves are used to specify the maximum permissible flow temperature (refer to clause 4.1.3.2 and Figure A.4).
1) National regulations may limit these temperatures to lower values. SIST EN 1264-3:2009
insinsins,sRλ=λ
(3) where sins
is the thickness of the insulating layer in m, and λins
is the thermal conductivity of the insulating layer in W/(mK). Depending on the construction of the floor heating system, the effective thickness of the insulating Iayer sins is determined differently: For floor heating systems with flat thermal insulating panels (see Figure A.2), sins is identical with the thickness of the thermal insulating panel. For floor heating systems with profiled thermal insulating panels (see Figure A.3), a surface-related weighted calculation is made for the effective thickness of the insulating layer sins:
TDs)DT(sslhins⋅+−⋅=
(4) For profiled thermal insulating panels shaped differently from that shown in Figure A.3, the average effective thickness of the insulating Iayer shall be mathematically verified with an accordant application of equation (4). NOTE
In cases where formula (4) is non-applicable, an accordant calculation method shall be applied. For instance, in the case of system plates with attachment studs, the accordant calculation is given through: sins = (Volume of plate with studs included, divided by AF).
2) National regulations may vary the requirements given in Table 1 of EN 1264-4. SIST EN 1264-3:2009
Ff,NdesAQq=
(5) The standard heat load QN,f shall be calculated in accordance with EN 12831. Normally, the heat output QF of the floor heating system shall be equivalent to the standard heat load QN,f. If this is not possible, additional heating surfaces shall be used, see equation (12). The design thermal output QF of the entire heating surface AF is calculated as follows:"
QF = q⋅AF
(6) Where peripheral area is used, q shall be distributed between the peripheral area AR and the occupied area AA according to a surface weighted calculation (see also clause 4.1.4):
AFARFRqAAqAAq⋅+⋅=
(7) where: qA
is the specific thermal output of the occupied area qR
is the specific thermal output of the peripheral area 4.1.3.2 Determination of the design flow temperature The design flow temperature is determined for the room (or the rooms respectively) with the highest value qmax = qdes of the specific thermal output (bathrooms excepted). In the rooms being heated, it is assumed that floor coverings with an uniform thermal conduction resistance are used. Generally for the design of floor heating systems in residential rooms, uniform floor coverings with R,B = 0,10 (m2⋅K)/W are assumed. In the case of using higher values R,B, these values shall be taken. For the room used for design, the temperature drop of the heating water is specified to σ ≤ 5 K. If necessary, a subdivision of this room into heating circuits should be performed. Under these conditions, the maximum value qmax may reach until the limit value qG of the specific thermal output (see Figure A.4)3. For the room with qmax, a pipe spacing is chosen with which qmax remains less or equal to the limit value qG (qmax ≤ qG, see Figure A.4). For this, small pipe spacing is recommended. In case of qmax ≤ qG, design values of the temperature difference between flow heating water and room ∆ϑV,des ≤ ∆ϑH,G+2,5 K are permitted (see Figure A.4). The maximum permissible temperature difference between flow and room comes to:
G,Hdes,Hdes,Hdes,Vwhere2/ϑ∆≤ϑ∆σ+ϑ∆=ϑ∆
(8) The temperature drop 1 in equation (8) and in equation (9), in figure A.4 is designated σdes.
Equation (8) is valid for σ/∆ϑH ≤ 0,5.
3) This means that above the flow pipe the maximum floor temperature ϑF,max can be exceeded compared with the centre of the room, corresponding to the higher heating water temperature by σ/2. SIST EN 1264-3:2009
des,H2des,Hdes,V122ϑ∆⋅σ+σ+ϑ∆=ϑ∆
(9) The result of Equation (8) or (9) provides the design flow temperature ϑV,des = ∆ϑV,des + ϑi. For all other rooms operated at the same flow temperature ϑV,des, for the ratio σ/ûϑH,j ≤ 0,5 the associated values for the temperature drop σj of the heatin
...




Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.
Loading comments...