SIST EN 771-2:2004

SLOVENSKI STANDARD
SIST EN 771-2:2004
01-januar-2004
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SIST EN 771-2:2000
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Specification for masonry units - Part 2: Calcium silicate masonry units
Festlegungen für Mauersteine - Teil 2: Kalksandsteine
Spécifications pour éléments de maçonnerie - Partie 2 : Éléments de maçonnerie en
silico-calcaire
Ta slovenski standard je istoveten z: EN 771-2:2003
ICS:
91.100.15 Mineralni materiali in izdelki Mineral materials and
products
SIST EN 771-2:2004 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 771-2:2004

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SIST EN 771-2:2004
EUROPEAN STANDARD
EN 771-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2003
ICS 73.020; 91.100.15 Supersedes EN 771-2:2000
English version
Specification for masonry units - Part 2: Calcium silicate
masonry units
Spécifications pour éléments de maçonnerie - Partie 2: Festlegungen für Mauersteine - Teil 2: Kalksandsteine
Eléments de maçonnerie en silico-calcaire
This European Standard was approved by CEN on 2 October 2002.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the 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 translation
under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2003 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 771-2:2003 E
worldwide for CEN national Members.

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SIST EN 771-2:2004
EN 771-2:2003 (E)
Contents
Foreword .3
1 Scope.4
2 Normative references.4
3 Terms and definitions.5
4 Materials and manufacture.7
5 Requirements for calcium silicate masonry units.7
5.1 General .7
5.2 Dimensions and tolerances .7
5.3 Configuration.9
5.4 Dry density.9
5.5 Compressive strength .10
5.6 Thermal properties.10
5.7 Durability.10
5.8 Water vapour permeability .11
5.9 Reaction to fire .11
5.10 Water absorption.11
5.11 Moisture movement .12
5.12 Bond strength.12
6 Description, designation and classification of calcium silicate masonry units.12
6.1 Description and designation.12
6.2 Classification.13
7 Marking.13
8 Evaluation of conformity .13
8.1 General .13
8.2 Initial type tests .14
8.3 Factory production control .14
Annex A (normative) Sampling for initial type testing and for independent testing of
consignments.16
Annex B (normative) Cutting schemes .19
Annex C (normative) Tolerances on accessory units.21
Annex D (informative) Classification systems.25
Annex ZA (informative) Clauses of this European standard addressing the provisions of
the EU Construction Products Directive .27
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SIST EN 771-2:2004
EN 771-2:2003 (E)
Foreword
This document (EN 771-2:2003) has been prepared by Technical Committee CEN/TC 125 ’Masonry’,
the Secretariat of which is held by BSI.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by October 2003, and conflicting national standards
shall be withdrawn at the latest by January 2005.
This document has been prepared under a mandate given to CEN by the European Commission and
the European Free Trade Association and supports the essential requirements of the EU Construction
Products Directive (89/106/EEC).
For relationship with EU Directive(s), see informative annex ZA, which is an integral part of this
document.
It also takes into account the general rules for reinforced and unreinforced masonry in Eurocode 6.
The annexes A, B and C of this documentare normative, the annexes D and ZA are informative.
This document supersedes EN 771-2:2000.
EN 771 Specification for masonry units consists of:
 Part 1: Clay masonry units
 Part 2: Calcium silicate masonry units
 Part 3: Aggregates concrete masonry units (dense and light-weight aggregates)
 Part 4: Autoclaved aerated concrete masonry units
 Part 5: Manufactured stone masonry units
 Part 6: Natural stone masonry units
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Czech
Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg,
Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and the United
Kingdom.
3

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SIST EN 771-2:2004
EN 771-2:2003 (E)
1 Scope
This document specifies the characteristics and performance requirements of calcium silicate
masonry units for which the main intended uses are inner walls, outer walls, cellars, foundations and
external chimneymasonry.
This document is intended to apply to all calcium silicate masonry units, including those of an overall
nonrectangular parallelepiped shape, specially shaped and accessory units.
It defines the performance related to e.g. strength, density and dimensional accuracy, measured
according to the corresponding test methods contained in separate European Standards.
It provides for the evaluation of conformity of the product to this European Standard. The marking
requirement for products covered by this document is also included.
This document does not specify standard sizes for calcium silicate masonry units, nor standard work
dimensions and angles of specially shaped and accessory units.
It does not cover units with more than 60 % volume of voids, nor products made from shale as a
major raw material.
It does not cover storey height panels.
It does not cover units intended for use as a damp proof course, nor units with an incorporated
thermal insulation material bonded to the faces of the unit susceptible to be exposed to fire nor
chimney flue units.
2 Normative references
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions of any
of these publications apply to this European Standard only when incorporated in it by amendment or
revision. For undated references the latest edition of the publication referred to applies (including
amendments).
EN 772-1:2000, Methods of test for masonry units — Part 1: Determination of compressive strength
EN 772-9, Methods of test for masonry units — Part 9: Determination of volume and percentage of
voids and net volume of calcium silicate units by sand filling
EN 772-13:2000, Methods of test for masonry units — Part 13: Determination of net and gross dry
density of masonry units (except for natural stone)
EN 772-16:2000, Methods of test for masonry units — Part 16: Determination of dimensions
EN 772-18:2000, Methods of test for masonry units — Part 18: Determination of freeze/thaw
resistance of calcium silicate masonry units
EN 1052-3, Methods of test for masonry — Part 3: Determination of initial shear strength
EN 1745, Masonry and masonry products — Methods for determining design thermal values
EN ISO 12572, Hygrothermal performance of building materials and products Determination of water
vapour transmission properties (ISO 12572:2001)
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SIST EN 771-2:2004
EN 771-2:2003 (E)
EN 13501-1, Fire classification of construction products and building elements —
Part 1: Classification using test data from reaction to fire tests
3 Terms and definitions
For the purposes of this European Standard, the following terms and definitions apply.
3.1
masonry unit
preformed component intended for use in masonry construction
3.2
calcium silicate masonry unit
masonry unit made predominantly from lime and siliceous materials, hardened by high pressure
steam
3.3
shale
fine grained sedimentary rock, finely laminated and consisting of mainly quartz and clay minerals
3.4
co-ordinating size
size of the co-ordinating space allocated to a masonry unit including allowances for joints and
tolerances
3.5
work size
size of a masonry unit specified for its manufacture, to which the actual size conforms within
permissible deviations
3.6
actual size
size of a masonry unit as measured
3.7
regular shaped masonry unit
masonry unit with an overall rectangular parallelepiped shape
3.8
specially shaped masonry unit
masonry unit which is not a rectangular parallelepiped
3.9
accessory unit
masonry unit which is shaped to provide a particular function, e.g. to complete the geometry of the
masonry. It may be obtained by cutting a large unit
3.10
interlocking feature
shaped matched projections and indentations on masonry units, e.g. tongue and groove systems
3.11
hole
formed void which may or may not pass completely through a masonry unit
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SIST EN 771-2:2004
EN 771-2:2003 (E)
3.12
perforation
formed void which passes completely through a masonry unit
3.13
cell
formed void which does not pass through a masonry unit
3.14
frog
depression formed in one or both faces of a unit, the total volume of all such depressions which does
not exceed a certain limit of the overall volume of the unit i.e. length · width · height
3.15
recess
a depression or indentation in one or more surfaces of a masonry unit (e.g. mortar pocket, rendering
keyway, grip hole)
3.16
shell
peripheral material between the hole(s) and the outer surfaces of a masonry unit
3.17
web
solid material between the holes in a masonry unit
3.18
normalized compressive strength of masonry units
compressive strength of masonry units converted to the air dry compressive strength of an equivalent
100 mm wide and 100 mm high masonry unit
NOTE See procedure given in Annex A of EN 772-1:2000
3.19
mean compressive strength of masonry units
arithmetic mean of the compressive strengths of masonry units
3.20
characteristic compressive strength of masonry units
compressive strength corresponding to the 5 % fractile of the compressive strength of masonry units
3.21
declared value
value that a manufacturer is confident of achieving, bearing in mind the precision of the test and the
variability of the manufacturing process
3.22
Category I masonry units
units with a declared compressive strength with a probability of failure to reach it not exceeding 5 %.
This may be determined via the mean or characteristic value
3.23
Category II masonry units
units not intended to comply with the level of confidence of Category I units
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SIST EN 771-2:2004
EN 771-2:2003 (E)
4 Materials and manufacture
Calcium silicate masonry units are produced predominantly from a mixture of lime and natural
siliceous materials (sand, crushed or uncrushed siliceous gravel or rock or a mixture thereof),
hardened by high pressure steam.
Calcium silicate masonry units produced with a majority of other siliceous materials are permitted if
these materials have no deleterious effect on the properties of the product. The presence of such a
material shall be declared.
5 Requirements for calcium silicate masonry units
5.1 General
The requirements and properties specified in this European Standard shall be defined in terms of the
test methods and other procedures referred to in this European Standard.
It should be noted that the test methods are not always applicable to specially shaped and accessory
units as defined in 3.8. and 3.9.
The conformity criteria given in the following sub-clauses relate to initial type testing (see 8.2) and,
when relevant, to consignment testing (see annex A). For the compressive strength of Category I
units use a 50 %-fractile (p=0,50) for mean values and a confidence level of 95 %.
For production evaluation the manufacturer shall define the conformity criteria in the factory
production control documentation (see 8.3).
5.2 Dimensions and tolerances
5.2.1 Dimensions
The dimensions of a calcium silicate masonry unit shall be declared in mm for length, width and
height, in that order. They shall be given in terms of work size.
NOTE Iin addition the co-ordinating size may be given. see Figure 1.
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SIST EN 771-2:2004
EN 771-2:2003 (E)
4
2
6
3
5
1
Key
1 Length 2 Width 3 Height
4 Bed 5 Face 6 Header
NOTE This relates to the normal use of the masonry unit in the wall.
Figure 1 — Dimensions and surfaces
When a specified number of calcium silicate masonry units is sampled from a consignment in
accordance with annex A and tested in accordance with EN 772-16 the tolerances shall be as
indicated in 5.2.2. The determination of length, width and height shall be by one measurement taken
approximately in the centre of each specimen (7.1 of EN 772-16:2000 method b)). When there is a
need to exclude irregular surfaces (tongues and grooves, grip holes, etc.) in providing the dimension,
method a) shall be used.
Dimensions and tolerances for accessory units shall be as given in annex C.
5.2.2 Tolerances
The actual deviations for the mean length, width and height and the actual deviations for individual
length, width and height shall be not greater than the permissible deviations as specified in Table 1.
Closer tolerances may be declared for one or more dimensions.
Actual deviations for the mean are differences between declared work sizes and the mean measured
values. Actual deviations for individual values are differences between the mean measured values
and the measured individual values.
These dimensional tolerances shall not apply to the direction perpendicular to the face of fracturing in
a one-side sliced unit.
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SIST EN 771-2:2004
EN 771-2:2003 (E)
Table 1 — Dimensional tolerances for calcium silicate masonry units (in millimetres)
Dimensions Calcium silicate masonry units for use with joints made of:
general purpose mortar and thin layer mortar
light-weight mortar
Mean height of sample work size height ± 2 work size height ± 1
Mean length of sample work size length ± 2 work size length ± 2
Mean width of sample work size width ± 2 work size width ± 2
Individual height mean height of sample ± 2 mean height of sample ± 1
Individual length mean length of sample ± 2 mean length of sample ± 2
Individual width mean width of sample ± 2 mean width of sample ± 2
NOTE For definition of general purpose mortar, light-weight mortar and thin layer mortar see 3.3 of
EN 998-2:2003
5.3 Configuration
The configuration of perforations, cells, shells and webs shall be declared. No tolerances are given for
these.
NOTE The manufacturer may also declare, whether the units comply with the limits for one or another of the
groups specified in relevant parts of Eurocode 6.
The total volume of frogs shall not exceed 20 % of the overall volume of the unit, i.e. length · width ·
height.
5.4 Dry density
5.4.1 Gross dry density
The manufacturer shall declare a minimum and a maximum value for the gross dry density. The
manufacturer may declare the gross dry density class according to annex D.2.
When a specified number of calcium silicate masonry units is sampled from a consignment in
accordance with annex A and tested and in accordance with EN 772-13, the mean gross density shall
comply with this declared values or declared density class.
5.4.2 Net dry density
If necessary for the intended use the manufacturer shall declare a minimum and a maximum value for
the net dry density. When a specified number of calcium silicate masonry units is sampled from a
consignment in accordance with annex A and tested in accordance with EN 772-13 the mean net dry
density shall comply with this declared values.
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5.5 Compressive strength
The mean compressive strength shall be declared by the manufacturer. The manufacturer shall also
declare the normalised compressive strength. This may be done according to the classification in
annex D.1.
NOTE EN 772-1 gives instructions on how to convert the mean compressive strength into the normalised
compressive strength.
In addition the manufacturer shall declare whether the calcium silicate masonry unit is Category I or
Category II (see annex ZA.2).
The declaration shall relate to and indicate the orientation(s) of the calcium silicate masonry units as
tested, the method(s) of bedding the calcium silicate masonry units and whether voids present are
2
intended to be fully filled with mortar. The declared value shall be not less than 5 N/mm .
When a specified number of calcium silicate masonry units is sampled from a consignment in
accordance with annex A and tested in accordance with EN 772-1 the mean compressive strength
shall not be less than the declared value.
When a strength class is declared the mean normalised compressive strength shall be not less than
the value for the strength class declared.
Individual values of compressive strength as determined in accordance with EN 772-1 shall be not
less than 80 % of the declared value.
When a strength class is declared the individual normalised compressive strength values within a
sample as tested shall be not less than 80 % of the value for the declared compressive strength class
according to the classification in annex D.1.
For calcium silicate masonry units with lengths ‡ 500 mm and/or heights ‡ 300 mm representative
portions may be cut for determination of compressive strength as specified in annex B. In all other
cases whole calcium silicate masonry units shall be tested.
The mean value of the compressive strength of three pieces cut according to annex B from any
calcium silicate masonry unit in a sample shall be not less than 90 % of the declared value. When a
strength class is declared the mean value of the compressive strength of three pieces cut according
to annex B from any one calcium silicate masonry unit in a sample shall be not less than 90 % of the
value for the corresponding class as defined in annex D.1. If the specimen does not meet the
requirement of 7.2.1 of EN 772-1:2000 it shall be ground.
The condition of the calcium silicate masonry units shall be oven dry as specified in 7.3.3. a) of
EN 772-1:2000.
5.6 Thermal properties
When relevant to the uses for which the unit is put on the market and in all cases for masonry units
intended to be used in elements subject to thermal insulation requirements, the manufacturer shall
provide information on the thermal properties of the masonry units. If so it shall be done by reference
to EN 1745 or alternatively to 5.3 and 5.4.
5.7 Durability
Calcium silicate masonry units to be used where there is a risk of freezing and thawing while in a wet
condition, shall be declared by the manufacturer to be freeze/thaw resistant for structural use and
visual aspects or for structural use only. When a specified number of calcium silicate masonry units is
sampled from a consignment in accordance with annex A and tested in accordance with EN 772-18,
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SIST EN 771-2:2004
EN 771-2:2003 (E)
the freeze/thaw resistance shall be confirmed. The freeze/thaw resistance shall be for structural and
visual aspects or for structural aspects only depending on the intended use.
For calcium silicate masonry units with lengths ‡ 500 mm and/or heights ‡ 300 mm representative
portions shall be cut for determination of freeze/thaw resistance as specified in annex B. In all other
cases whole calcium silicate masonry units shall be tested.
When freeze/thaw resistance is declared for structural and for visual aspects there shall be no
significant damage of one of the categories in clause 7 of EN 772-18:2000. When freeze/thaw
resistance is declared for structural aspects only, the reduction in compressive strength as defined in
clause 7 of EN 772-18:2000 shall be no more than 20 %.
5.8 Water vapour permeability
When relevant to the uses for which the calcium silicate masonry unit is put on the market and in all
cases for masonry units intended to be used in external elements, the manufacturer shall provide
information on the water vapour permeability through the water vapour diffusion coefficient tabulated
values given in EN 1745 or determined in accordance with EN ISO 12572.
5.9 Reaction to fire
For units intended to be used in elements subject to fire requirements the manufacturer shall declare
the reaction to fire classification of the masonry unit.
For masonry units containing £ 1,0 % by mass or volume (whichever is the most onerous) of
homogeneously distributed organic materials the declaration may be fire Class A1 without the need to
test.
Masonry units containing > 1,0 % by mass or volume (whichever is the most onerous) of
homogeneously distributed organic materials shall be classified in accordance with EN 13501-1 and
the appropriate reaction to fire class declared.
NOTE Attention is drawn to the Commission Decision 96/603/EC, as amended by Commission Decision
2000/605/EC, in which non-combustible masonry units containing not more than 1,0 % (by mass or volume
whichever is more onerous) of homogeneously distributed organic materials are classified as reaction to fire
Class A1 without testing.
5.10 Water absorption
When relevant to the uses for which the units are put on the market and for all units intended to be
used in external elements, the water absorption of a consignment of masonry units shall be declared
by the manufacturer. When sampled in accordance with annex A and tested as below, the mean of
the values of the water absorption shall be not greater than the declared water absorption.
Method of test
 Dry the specimens to a constant mass in a ventilated oven at a temperature of 105 °C ± 5 °C and
weigh them to obtain m . Constant mass is reached if during the drying process in two
dry,s
subsequent weighings with a 24 h interval, the loss in mass between the two determinations is
not more than 0,1 % of the total mass.
 Allow the specimens to cool at room temperature.
 When cool, soak the specimens by fully immersing them in water for (48 ± 1) hours. Wipe off
surface water and weigh them to obtain mso,s.
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SIST EN 771-2:2004
EN 771-2:2003 (E)
 Calculate the water absorption of each calcium silicate masonry unit to the nearest 0.1 % using
the following formula:
m-m
so,s dry,s 2
c = · 10 (%)
w
m
dry,s
where c = water absorption for calcium silicate masonry units (%)
w
 Calculate the mean of the values of the water absorption to the nearest 0.1 % (m/m)
5.11 Moisture movement
When required, moisture movement shall be declared by reference to national provisions in place of
the use of the product.
5.12 Bond strength
5.12.1 General
For calcium silicate masonry units intended to be used in elements subjected to structural
requirements the bond strength of the unit in combination with mortar shall be declared in terms of the
characteristic initial shear strength in accordance with EN 1052-3. The declaration may be made
either on the basis of fixed values as in 5.12.2 below or tests as in 5.12.3 below. The manufacturer
shall declare whether the value of bond strength has been obtained from the fixed values or from test.
NOTE In most cases it is expected that the use of fixed values will be sufficient.
5.12.2 Declaration based on fixed values
When no declaration is made under 5.12.2 the characteristic initial shear strength of the unit in
combination with mortar may be declared by reference to EN 998-2:2003, annex C.
5.12.3 Declaration based on tests
The characteristic initial shear strength of the unit in combination with a specific type of mortar
specified in accordance with EN 998-2 may be declared based on tests on masonry units sampled
from a consignment in accordance with annex A and tested in accordance with EN 1052-3. The
characteristic initial shear strength shall not be less than the declared value.
NOTE Bond strength depends on the mortar, the masonry unit and the workmanship.
6 Description, designation and classification of calcium silicate masonry
units
6.1 Description and designation
The description and designation of a calcium silicate masonry unit shall comprise at least the
following:
a) number and date of issue of this European Standard;
b) work size dimensions (see 5.2); for non-rectangular units the slanting angle may be declared;
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EN 771-2:2003 (E)
c) suitability for use with thin layer mortar;
d) configuration (see 5.3);
e) compressive strength (see 5.5);
f) gross dry density (see 5.4.1).
When relevant to the uses for which the unit is put on the market the description and designation shall
include:
g) net dry density (see 5.4.2);
3
h) volume of voids intended to be fully filled with mortar, in mm (if applicable);
i) thermal properties (see 5.6);
j) durability (see 5.7);
k) water absorption (see 5.10).
6.2 Classification
Specification of the properties of calcium silicate masonry units may be given by reference to
classification systems provided those systems are based only on single properties included in this
standard and do not themselves constitute a barrier to trade.
This does not remove the requirement that all manufacturers claiming compliance with this standard
shall state declared values of the properties of their products, when required.
NOTE Details of classification systems in current use may be given in informative National Annexes.
7 Marking
The following particulars shall be clearly marked on one of the following: the units, the packaging, the
delivery note or any certi
...