Technical Report and Design Guidance for the use of Porotherm Blocks in the UK

Special Publication 147

January 2010

About CERAM CERAM is an internationally renowned centre for consultancy and testing in the materials world. CERAMs involvement in masonry materials dates back to its formation in the 1920s. Initially from a manufacturing perspective and since the 1960s it has been central to the generation and interpretation of data to support the development of British Standards and Codes of Practice and more recently their European counterparts. Through large testing programmes at their extensive laboratories in Stoke-on-Trent, information has been produced covering large areas of design e.g. lateral loading of masonry walls, reinforced and pre-stressed masonry, durability, compressive strength of walls, shear strength. In many cases, the sequence has been the development of test data, all of which has been published, and the development of design approaches which have been published as authoritative guides for practicing designers. These have then formed the basis for Code of Practice guidance. CERAM occupies a central role at the British Standards Institution (BSI) and the European Committee of Standardisation (CEN), providing Chairmen, leaders of delegations and conveners and is well placed to help in the development of guidance for Porotherm. CERAM also provides project specific information for schemes, which because of their unique nature need bespoke assistance. Good examples are Glyndebourne Opera House, Portcullis House, Kelvingrove Museum and Art Gallery and La Poste, Marseilles. CERAM is UKAS accredited to the recognised international standard ISO/IEC 17025:2005 as both a testing laboratory (No 0013) and a calibration laboratory (No 0420). It is a Notified Laboratory to the European Commission and a member of AIRTO, the Association of Independent Research & Testing Organisations. About this Report and Guide Porotherm* masonry has a long history of successful use in mainland Europe but is relatively new to the UK. Although the units themselves comply with the relevant product standard BS EN 771-1 and carry the CE mark, guidance on their use is not in the Code of Practice BS 5628. Although EN 1996 the Eurocode for masonry will be the new means of designing masonry in 2010 designs to BS 5628 will continue to be done for a long time. In order to meet the requirements of the Building Regulations this Technical Report and Guide is aimed at demonstrating that Porotherm masonry can be designed so as to incorporate an equivalent level of safety to design to BS 5628. In 2010, a new version will be produced to provide the same confidence in relation to Eurocode 6. As a consequence there is no need for Porotherm masonry to be covered by independent certification although some of the components may do. This Technical Report and Guide has been drafted in a similar way to a Code of Practice and much of the terminology should be familiar. Where values are given for use in the design the supporting test data is included in the many annexes. From time to time revisions and updates are planned which will cover some of the less usual applications of Porotherm masonry. *Porotherm is a Wienerberger Group brand.

Technical Report and Design Guidance for the Use of Porotherm Blocks in the UK General Introduction Porotherm blocks are highly perforated clay blocks manufactured by Wienerberger intended for use in masonry which is protected against water penetration. Protection may be provided to external masonry by suitable render or cladding or by its location as an inner leaf in cavity walling or as an internal partition. The blocks are supplied in thicknesses ranging from 100mm to 365mm and are placed on a bed of Porotherm Bed Joint Mortar. The bed surfaces of the blocks are ground flat and parallel such that the target thickness of the bed joint is 1mm. The cross-joints are formed by interlocking features in the header ends of the unit and contain no mortar. Porotherm blocks have a long history of use in mainland Europe and comply with the European Standard BS EN 771-1. However, as clay blocks have not been used extensively in the UK for many years masonry made from them is not covered by UK Codes of Practice. The aim of this Technical Report and Guide is to provide that guidance so that Porotherm masonry may be designed in the UK with confidence that it meets regulatory requirements. The UK Code of Practice BS 5628 will be replaced by EN 1996, the Eurocode for masonry design in the Spring of 2010; however, designs to BS 5628 will continue to be accepted in the UK probably for several years. A new edition of this Technical Report and Guide will be produced to be compatible with the provisions of EN 1996 and to provide the specific data to enable it to be successfully used to design Porotherm masonry. Scope This Technical Report and Guide cover the use of Porotherm Blocks with Porotherm Bed Joint Mortar for protected masonry. References BS 476 BS 4315 BS 5628 BS 5262 BS 8104 Fire tests on building materials and structures Part 20:  Method for determination of the fire resistance of elements of construction (general principles) Methods of test for resistance to air and water penetration Part 2: Permeable walling constructions (water penetration) Code of practice for use of masonry: Part 1: Structural use of unreinforced masonry Part 3: Materials and components, design and workmanship Code of practice for external renderings Code of practice for assessing exposure of walls to wind driven rain

BS 8215  Code of practice for the design and Installation of damp proof courses in masonry construction BS EN 771 BS EN 772 BS EN 845 Specification for masonry units: Part 1: Clay masonry units Methods of test or Masonry units: Part 1: Determination of compressive strength Specification for ancillary components for masonry: Part 1: Ties, tension straps, hangers and brackets Part 2: Lintels

BS EN 846 Methods of test for ancillary components for masonry:  Part 4:   Determination of load capacity and load deflection characterisation of straps  Part 5:  Determination of tensile and compressive load capacity and load displacement characteristics of wall ties (couplet test)  Part 8:  Determination of load capacity and load deflection characteristics of joist hangers Part 9: Determination of flexural resistance and shear resistance of Lintels BS EN 998 Specification for Mortar for Masonry: Part 1: Rendering and plastering mortar Part 2: Masonry mortar

BS EN 1015 Methods of test for mortar for masonry:  Part 11:  Determination of flexural and compressive strength of hardened mortar BS EN 1052 BS EN 1365 Methods of test for masonry: Part 1: Determination of compressive strength Part 2: Determination of flexural strength Part 3: Determination of initial shear strength Part 4: Determination of shear strength including damp proof course Methods for determination of: Part 1: The fire resistance tests for loadbearing elements. Walls

BS EN 1996 Eurocode 6 design of masonry structures: Part 1.1: General Rules for reinforced and unreinforced masonry structures Part 1.2: General rules for structural fire design  Part 2:  Design considerations, selection of materials and execution of masonry Communities and Local Government, The Building Regulations 2000 (as amended) and the Approved Documents

Symbols A B fk fkx fv fvko gA U m mv slope of the line relating shear strength with pre-compression slope of the line relating shear strength including a d.p.c. with precompression characteristic compressive strength of masonry (N/mm2) characteristic flexural strength of masonry (N/mm2) characteristic shear strength of masonry (N/mm2) characteristic initial shear strength of masonry (N/mm2) design vertical load per unit area of wall section (N/mm2) heat flow per unit area per degree temperature difference (W/m2K) partial safety factor for material strength partial safety factor for the shear strength of material

2 Materials and Components 2.1  General   The materials and components used in Porotherm masonry should all meet the requirements of the relevant British Standard. 2.2  Masonry Units  Porotherm masonry units meet the requirements of BS EN 771-1: 2003. The units meet the requirements for LD units and are vertically perforated with a tongue and groove system on their header ends. LD units are those with a gross dry density less than or equal to 1000kg/m3 for use in protected masonry. Typical properties of the core range of Porotherm blocks are given in Table 1. Table 1. Properties of the Core Range of Porotherm Blocks
Block Type Porotherm 100 Porotherm 140 Porotherm 190 Porotherm 365 (T12) Dimensions l x w x h (mm) 300 x 100 x 224 300 x 140 x 224 300 x 190 x 224 248 x 365 x 249 Typical Mean Compressive Strength (N/mm2) 10 10 10 10

Porotherm blocks all carry the CE mark and the information that is required to be declared together with the mark is given in Annex A 2.3 Masonry Mortar

  Porotherm masonry is constructed using Porotherm Bed Joint Mortar, which is supplied with the blocks and complies with BS EN 998-2.

2.4 Rendering Mortar 2.4.1  Rendering Mortar for Porotherm 365 Masonry The system to be used consists of: a)  a base coat of lightweight render in accordance with BS EN 998-1. The strength classification is CS11 and the capillary water absorption is class W2 b) a ready to use acrylic based liquid primer c) a finishing coat silicon resin based decorative render The System Chosen for Testing consisted of: a) MP69 b) DG27 c) SiliconPutz and was supplied by Baumit GmbH

2.4.2 Rendering Mortar for Porotherm 100 Masonry  Testing work is in progress and will be reported later. In the interim please refer to the Baumit Technical Guidance. 2.5 Damp Proof Courses  The damp proof course to be used in Porotherm masonry is a Co-Polymer Thermoplastic. The system chosen for testing was Zedex CPT High performance DPC which meets the requirements of BBA Certificate 94/039. Zedex damp proof systems are manufactured by Visqueen. 2.6 2.7 Wall Ties The wall ties to be used in Porotherm masonry comply with the requirements of BS EN 845-1 and are classified as Type 3 to BS 5628 1: 2005 (Annex C). Ancon Building Products supplied the ties used in the experimental programme. Tension Straps Tension Straps shall comply with the requirements of BS EN 845-1.

2.8 Lintels  Lintels to be used in Porotherm masonry comply with the requirements of BS EN 845-2. Lintel bearing blocks comply with BS EN 771-1. Keystone Lintels Ltd. supplied the lintels used in the experimental programme. Wienerberger distributors supply lintel-bearing blocks. 2.9 Fixings Fixings for use with Porotherm masonry are classified into four types by end use these are: a) Light Duty e.g. battens, curtain rails, light shelving, bathroom cabinets b)  F acade Fixing e.g. anchorage of baths, wall plates, beams and frames, supports and rails c) L  ight-Medium Duty e.g. doorframes, battens for cladding, shelving, external fixtures and fittings d) Heavy Duty e.g. door frames, wall plates, designed fixings

Recommended fixing types for the four classes are: a) Universal nylon plug with or without collar, wood or chipboard screws b) Polyamide expanding anchor sleeve with safety screws c) Polyamide expanding anchor sleeve with safety screws d)  Injection anchor plastic sleeve used in conjunction with a hybrid vinyl ester resin and threaded rod fischer supplied the products used in the testing programme.

3 Structural Use of Masonry 3.1  General   The structural design of Porotherm masonry shall follow the guidance in BS 5628-1. The characteristic values of the properties of Porotherm masonry have been derived by testing in accordance with BS EN 1052. The test results and recommended values are given in the following clauses. 3.2  Characteristic Compressive Strength of Porotherm Masonry, fk  The characteristic compressive strengths for use in design with Clause 19 of BS5628: Part 1 is given in Table 2. Table 2. Characteristic Compressive Strength of Porotherm Masonry, fk
Block Type Porotherm 100 Porotherm 140 Porotherm 190 Porotherm 365 (T12) Dimensions l x w x h (mm) 300 x 100 x 224 300 x 140 x 224 300 x 190 x 224 248 x 365 x 249 Typical Mean Compressive Strength (N/mm2) 5.0 5.0 4.5 3.0

The characteristic values given in Table 2 are derived from the formula given in EN 1996-1-1 and rounded for convenience. Experimental data is available for all of the masonry types and indicates that the approach taken is conservative. The experimental results are given in full in Annex B. 3.3 Flexural Strength of Porotherm Masonry, fkx

  The flexural strengths of Porotherm masonry recommended by Wienerberger for use in design with clause 20 of BS 5628: Part 1 are given in Table 3. It should be noted that tests in accordance with BS EN 1052-2 have been carried out such that the parge coat was on the tension face and also with it on the compression face. As the designer will need to design against both positive and negative wind loads, the values used should be based upon the lower of the two results and engineering judgement. The complete set of experimental results is given in Annex C. Typical failures are shown in Annex H.

Table 3. Mean Flexural Strength of Porotherm Masonry

Block Thickness (mm) 365 100 Mean Flexural strength (N/mm2) Parallel 0.15 0.30 Normal 0.10 0.20

3.4

Characteristic Shear Strength of Porotherm Masonry, fv The characteristic shear strength of Porotherm masonry is given by fv = fvko + A.gA



  Where fvko is the characteristic initial shear strength in N/mm2 and gA is the design vertical load per unit area of wall cross section calculated from the appropriate load condition.  For Porotherm masonry fvko and A may be taken as 0.15 N/mm2 and 0.3 for 365mm units.   For 100mm units fvko and A may be taken as 0.40 N/mm2 and 0.2. No upper limit has been given for fv as this is limited by the characteristic compressive strength of the masonry and the partial safety factor to values lower than the limits given in BS 5628-1.   The complete set of experimental results in accordance with BS EN 1052-3 is given as Annex D.   The lower values of both fvko and A i.e. 0.15N/mm2 and 0.2 should be used for the 140mm and 190mm block widths. 3.5  Characteristic Shear Strength of Porotherm Masonry Containing a Damp Proof Course, fv

 The characteristic shear strength of Porotherm masonry containing a DPC is given by fv = fvko + B.gA

 When fvko is the characteristic initial shear strength in N/mm2 and gA is the design vertical load per unit wall area of wall cross section due to vertical loads calculated from the appropriate loading condition.   For Porotherm masonry made from 365mm units fvko may be taken as 0.05 N/mm2 and B as 0.1. For 100mm units fvko may be taken as 0.05 N/mm2 and B as 0.  The Complete set of experimental results in accordance with BS EN 1052-4 is given as Annex D.

4 Performance of Ancillary Components 4.1  Lintels  Inner leaf lintels were tested in accordance with BS EN 846-9. The load capacity is based upon the maximum load sustained in the flexural strength test i.e. the flexural resistance. In all cases, the shear resistance exceeded half of the flexural resistance and hence is more than adequate. The load capacity as derived from the flexural testing is given in Table 4. The individual results are given in Annex E. Typical failures are shown in Annex H.   All the lintels tested were 1200mm or 2550mm long and hence the spans have varied a little dependant on the bearings onto the Wienerberger bearing blocks. Safe Working Loads have been calculated based upon a global safety factor of 1.6 in accordance with the National Annex to BS EN 845-2. In all cases at the Safe Working Load the average deflections were less than span/325 which is the guidance figure given in the National Annex to BS EN 845-2.  The values in Table 4 in brackets i.e. 18 and 20 is the Safe Working Load recommended by Keystone Lintels who provided them for the test programme. The Safe Working Loads as recommended by Keystone and which should be used for design purposes are given in Annex E. Table 4. Load Capacities and Safe Working Loads for Lintels
Clear Span (mm) 1000 2300 800 2250 1080 2190 Load Capacity (kN) Block Thickness (mm) 100 57.1 38.6 Block Thickness (mm) 140 43.0 49.1 Block Thickness (mm) 190 56.4 61.4 35.2 (18) 38.4 (20) 26.9 (18) 30.7 (20) 35.7 (18) 24.1 (20) Safe Working Load SWL (kN)

 Porotherm masonry made with 365 (T12) blocks requires the use of two lintels side by side. This configuration was tested in accordance with BS EN 846-9 with a spreader plate across both lintels i.e. they were tested as a single lintel. The Safe Working Loads have been calculated as before, based upon the flexural failure. The calculated values were 62.3kN for the 2550mm lintel and 44.1kN for the 1200mm lintel which compare with 40kN and 36kN which are the values recommended by Keystone. The deflections at the Safe Working Load were less than span/325 in each case. The individual results are given in annex E as are the Safe Working Loads recommend by Keystone, which should be used for design.

4.2  Fixings

 In the testing programme to support the above recommendations the products used complied with the following requirements: a) Light Duty: Manufacturers declarations b) F  acade Fixing: General Approval Z-21.2-1204 (Deutsches Inst. for Bautechnik) c) Light-Medium Duty: European Technical Approval ETA-07/0121 d) H  eavy Duty: General Approval Z-21.3-1824 (Deutsches Inst. for Bautechnik) 4.3 For design information and the experimental results see Annex F. Joist Bearings

 It is recommended that joist hangers should not be used with Porotherm blocks but that the joist be built in, preferably using a joist end cap.  In order to check that with narrow, commonly used joists the bearing was satisfactory 38mm and 50mm wide joists 225mm deep were tested in a 100mm deep end cap in a 100mm thick Porotherm masonry wall. The test followed the principles for testing joist hangers to BS EN 846-8. In all cases the joist failed in bending before any damage to the Porotherm blockwork occurred.  The mean failure loads for the 38mm joists were 21.81kN and for the 50mm joists were 22kN. A general value of the Safe Working Load for these joist sizes may be taken as 8kN, which is comparable to that for steel hangers onto dense aggregate blockwork. For larger joist sizes specialist advice should be sought. Typical joist failure is shown in Annex H. 4.4 Tension Straps

4.4.1 Horizontal Restraint Straps

 Heavy Duty 27.5mm x 5mm tension straps, 1200mm long were tested in a horizontal altitude, this represents the strap as used to restrain the inner leaf of a cavity wall by connecting it to a floor joist. The strap passed through a 100mm Porotherm leaf and was connected to a timber joist using 5 No. 3.35mm x 35mm square twist sheradised nails. The block above the bed joint was notched to accommodate the strap thickness. The straps were tested in accordance with BS EN 846-4. The result showed that the mean result for the masonry embedded end was 11.2kN and for the timber end was 11.3kN. Consequently, with the recommended fixings into the timber the straps when used with Porotherm masonry comfortably exceed the value of 8kN required by the National Annex to BS EN 845-1. The full experimental results are given in Annex G. Expamet supplied the straps used in the experimental programme. A typical failure is shown in Annex H. 

4.4.2 Vertical Restraint Straps

 Standard 27.5mm x 2.5mm tension straps were used and were fixed using four Fischer Nylon UX plugs (UX10 x 60R) with 60mm No,12 (6mm) screws. The straps were tested in accordance with BS EN 846-4. The results were a mean value of 8.2kN for the masonry end and a mean value of 7.3kN for the timber header end. These values comfortably exceed the 4kN commonly quoted for these straps. BS EN 845-1 requires that the tensile capacity of straps with their recommended fixings be declared. These values may be used to design connections to resist the wind uplift on roofs. The full results are given in Annex G. Expamet supplied the straps used in the experimental programme. 4.5 Wall Ties

 Indicative tests to BS EN 846-5 on wall ties gave mean results of 1317kN (mean of three) in tension and 916 (mean of four) in compression. Although these values will need to be confirmed on production ties they meet the requirements for a Type 3 tie to BS 5628 Part 1 (1100kN and 800kN). The individual results are given in Annex J. 5 Partial Safety Factors for Material Strength, 5.1  General
m m

mv

 The principle followed in BS 5628 is that the value of to the quality control that has been exercised. 5.2 Quality Control

to be used in design is related

 5.2.1 Manufacturing Control  Porotherm blocks are declared as being Category 1 masonry units in accordance with Annex A. The mortar is a factory made mortar and complies with BS EN 998-2. 5.2.2 Construction Control

 If the specification, supervision and control of the construction ensure that the requirements of Section 7 and the Wienerberger requirements are met, the Special Category of Construction Control may be assumed, if not, then Normal Category should be assumed. 5.3 Value of
m

and

mv

for Normal and Accidental Loads

 The values of m to be used in design are given in Table 5. These are based upon BS 5628 together with the considerations in clause 5.2. Table 5. Partial Factors for Material Strength
Category of Construction Control Compression and Flexure
m

Special 2.5

Normal 3.1

 he value for flexure given in BS 5628 has been harmonised (upwards) with that for T compression for ease of use. When considering the possible effects of misuse or accident it would be usual to half these values.

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  The value for the practical safety factor for masonry in shear mv is recommended to be 2.5 as in BS 5628 and that as with compression and flexure in cases of misuse or accident this value may be halved.  The value for the partial safety factor to be applied to the strength of wall ties conforming to BS EN 845-1 should be 3.5. When considering the effects of misuse or accident, this may be halved. 6 Design Data: Other Important Considerations 6.1  Exclusion of Water  Porotherm masonry units meet the requirements for LD units to BS EN 771-1 and hence are intended for use in masonry protected against water penetration. Protected masonry includes internal masonry and that in the internal leaves of external cavity walls. In the external leaves of cavity walls or in monolithic (single leaf) external walls the masonry must be protected by cladding or render.  When Porotherm masonry is used in the inner leaves of cavity walls the guidance on exclusion of water is no different to that for other types of cavity walling. The inner leaf is not relied upon to resist the passage of water and hence the relevant guidance is that in BS 5628-3 which applies to the outer leaf and any materials bridging the cavity. Care needs to be taken over the construction of the outer leaf, mortar joint finish etc. and particularly over the positioning of damp proof course materials, cavity trays and weepholes and any insulation in the cavity. Detailed guidance is given in BS 5628-3.  Where Porotherm masonry, rendered in accordance with BS 5262, is used in the external leaf of a cavity wall the guidance in BS 5628-3 is relevant. Damp proof courses and cavity trays should be installed following the provisions of BS 5628-3, BS 8215 and manufacturers instructions. In the case of cavity trays it is preferable to include weepholes as although not strictly required by BS 5628-3 water may at some stage enter the cavity through defects and should have a clear route to escape. Weepholes would normally be placed at approximately 900mm centres with a minimum of two per cavity tray, common practice is to include a proprietary device which tapers from the cavity to the outer face to reduce the visual impact. It is recommended that partial fill insulants and a clear cavity be provided in these situations.  Rendered monolithic (single leaf) Porotherm masonry walls may be used as the external walls of buildings. Providing the rendering is in accordance with BS 5262 and manufacturers instructions walls made from blocks 365mm thick will be suitable in conditions of severe exposure (as defined in B S5628-3 using the local spell index from BS 8104).  A Porotherm masonry wall was built from 365mm thick blocks into a frame 1.8m square. The wall was rendered on the outer face and parged on the inner. The wall was subjected to a rain penetration test following the principles of BS 4135 Part 2.

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  The test regime was: Day 1: Continuous spray over a 6-hour period at zero applied air pressure Day 2: Continuous spray over a 6-hour period at 250 Pa applied air pressure Day 3: Continuous spray over a 6-hour period at 500 Pa applied air pressure  This is a severe test and the spray rate at 0.5 l/min/m2 was equivalent to 53mm rain/hour or 322 mm rain/spell which is three times the amount of rain regarded as very severe exposure in BS 8104, the Code of Practice for assessing exposure of walls to wind driven rain.  No water was observed to reach the inner face of the panel. In order to check whether water was passing through the render and accumulating within the wall approximately 200mm of the wall thickness including the parge coat was removed from the wall and it was retested. The testing replicated the BS 4315 test regime but with two hours application at each air pressure. No water could be detected within the blocks.  215mm rendered aircrete construction is considered in BS 5628 Part 3 to be suitable for severe exposure. This form of construction with a traditional three coat render system was tested using the same testing regime as that for the 365mm Porotherm masonry wall. No leakage was detected and hence the Porotherm wall should also be suitable for conditions of severe exposure. 6.2  Durability

 Traditionally in the UK durability of clay masonry had been taken to include resistance to freeze thaw action and also to the attack on cement in mortar by sulfates derived from the clay units or other external sources. Porotherm masonry units are supplied as LD units to BS EN 771-1 and hence there are no requirements for freeze thaw resistance and no limits to the levels of soluble sulfate in the blocks. Deterioration of clay units due to freeze thaw action occurs when they are in an exposed situation such that they become saturated and are subjected to repeated freezing and thawing. Sulfate attack is associated with the movement of water through the clay units such that sulfates are dissolved and transported to be in contact with the cement in the hardened mortar. Sulfates attack the tricalcium aluminate in the cement to form calcium sulfoaluminate (etteringite) which leads to cracking of the mortar. The causes of both forms of disruption are related to the ingress of water and the Porotherm system relies upon the protection offered by the external render and the damp proof detailing to ensure that the blockwork is adequately protected against water. 6.3  Fire Resistance

 The Reaction to Fire of clay masonry units is needed to be declared if they are to be used in elements which are subjected to fire requirements. Porotherm masonry units are declared as Class A1 without any need to test, in accordance with decisions of the European Commission. Nevertheless a wall constructed of Porotherm 100 blocks and finished both faces with a plaster finish, 10-15mm thick was tested to determine its fire resistance in accordance with BS EN 1365-1:1999 at Exova Warringtonfire under reference WF Report No. 186546. 

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  The wall was subjected to vertical load of 96kN (stress of 0.32 N/mm2) and after 78

minutes the maximum temperature at the cold face exceeded the test criterion. The test was terminated after 132 minutes. A brief extract of the test report is included as Annex J with the permission of Exova Warringtonfire. Thermal Performance

6.4

 The thermal transmittance which is the heat flow through the wall construction per square metre for a one degree difference in temperature (U value) depends on the wall construction. The value is calculated using the design thermal resistance of the wall including any finishes and the cavity, if one exists. Wienerberger provide a U value indicator on their website. As an indication the design thermal resistance values for Porotherm 100, 140 and 190 masonry together with a parge coat may be taken as 0.40, 0.56 and 0.73m2 K/W respectively. The thermal resistance value of a Porotherm 365T12 masonry wall with no finishes may be taken to be 3m2 K/W. 6.5  Sound Control

 The weighted sound reduction index for each block in the Porotherm range has been evaluated by tests and calculations for a walling with plaster on both faces. The results are shown in Table 6. Further information may be obtained from Wienerberger. Table 6. Weighted Sound Reduction Indeces
Plaster Type (face1) Density (kg/m3), thickness (mm) Cement lime plaster 1800, 20 Cement lime plaster 1850, 15 Cement lime plaster 1800, 20 Cement lime plaster 2000, 17 Plaster Type (face2) Density (kg/m3), thickness (mm) Cement lime plaster 1800, 20 Cement lime plaster 1850, 15 Cement lime plaster 1800, 20 Cement lime plaster 1900, 14 Weighted Sound Reduction Index (dB) 40 43 51 46

Block Type

Porotherm 100 Porotherm 140 Porotherm 190 Porotherm 365 (T12)

6.6  Movement

 The general advice from Wienerberger is that vertical movement joints to deal with thermal and moisture related movements are not generally required unless continuous lengths of masonry exceed 20m. However, the normal considerations for short returns and highly fenestrated elevations apply. Where Porotherm masonry is being used to infill within framed structures, careful consideration needs to be given to restraint ties to vertical columns and deflection joints at the head of panels. In all cases, a structural engineer should consider and allow provisions for movement.

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7 Workmanship 7.1  Preparation of Mortar  The Wienerberger Installation Manual should be considered as the minimum requirements for building successful Porotherm masonry. Porotherm Bed Joint Mortar is a factory made bagged mix which is mixed with water. One bag of the material (25kg) is mixed with 7.5l of clean water; only enough bed joint mix should be produced for immediate use. The mix is prepared in a mixer or a clean bucket using a drilling machine and agitator. The mixture is mixed until it has a honey like consistency and contains no lumps, it is then left for some five minutes and then stirred gently and is ready to use. 7.2 Laying Blocks

 The initial course is laid on a bed of conventional mortar. This bed may need to be thicker than subsequent ones in order to allow for any imperfections in the floor slab or foundation from which the wall is being built. This layer is extremely important as any imperfections will be amplified as the wall is raised, as there is very little room for adjustment of the subsequent thinner joints. The first course is laid carefully to line and level which may be by traditional means, i.e. spirit level and stringline or more sophisticated laser levelling arrangement. Prior to applying the bed joint mix the bed surface of the units is brushed with a damp brush. Mortar may be applied using a rolling device or by the dipping method. Please refer to the Wienerberger Installation Manual. Lintels are placed on the pre-cut shoulder units and the bed joint above is usually placed in a conventional mortar to allow for any levelling tolerances. 7.3  Applying the Render System

 The render manufacturers instructions should be followed.

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Annex A: CE Marking Information  Each of the block types used in Porotherm masonry carries the CE mark. This means that the blocks meet the legal requirements in all of the countries of the EEA. There is also a presumption that if the blocks are used to construct buildings then they will meet all of the relevant requirements of the Construction Products Directive e.g. mechanical stability. The properties of the Porotherm blocks that are declared in support of the CE mark are summarised in the table below.
Property Dimension and Tolerance Length (mm) Width (mm) Height (mm) Tolerance Class, l,w,h(mm) Range Class, range, l.w.h (mm) Gross Dry Density (Kg/m )
3

Porotherm 100 300 100 224 T1+7.0,4.0,1.0 R1+10.0,6.0,1.0 950 D1 10 2 48 -, 14 1 y = 0.29

D

Porotherm 140 300 138 224 T1+7.0,5.0,1.0 R1+10.0,7.0,1.0 850 D1 10 2 53 -, 13 1 y = 0.26

D

Porotherm 190 300 188 244 T1+7.0,5.0,1.0 R, 10.0, 8.0,1.0 850 D1 10 2 53 -, 12 1 y = 0.26
D

Porotherm 365 (T12) 300 365 249 T1+ 6,8,1 R1+ 9,11,1 620 D2 5 3 58 58 10, 12.5 1 y equ

Density Category Density Percentage (%) Group (to EN 1996-1-1) Volume of Formed Voids (%) Area of Voids on Bed Face (%) Compressive Strength. Mean, Normalised (N/mm2) Strength Category Bond Strength (N/mm2) Thermal Conductivity Water Absorption (%) Initial Rate of Water Absorption (Kg/m2-min) Reaction to Fire Flatness of Bed Faces Plane Parallelism (mm)

0.3

0.3

0.3

= 0.118 A1 1 1

18 2 A1 0.5 1

18 2 A1 0.5 1

18 2 A1 0.5 1

Annex B: Masonry Compressive Strengths  The tables give the data used to support the values given as characteristic values in Table 2. The tests were in accordance with BS EN 1052-1, BS EN 772-1 and BS EN 1015-11 as appropriate. The tests were carried out at the Wienerberger Technicum Laboratory and reviewed by CERAM.

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Table B1: Porotherm 100

Mean Mortar Strength (N/mm2) Mean Unit Strength (N/mm2) Normalised Unit Strength (N/mm2) Masonry Strength (N/mm2) Specimen 1 2 3 4 5 6 Mean Value (N/mm2) Characteristic Compressive Strength (N/mm2) 11.7 9.9 10.7 9.7 7.7 10.8 10.1 7.7 Flexure 4.6 14.6 20.2 Compression 26.1

Table B2: Porotherm 140

Mean Mortar Strength (N/mm2) Mean Unit Strength (N/mm2) Normalised Unit Strength (N/mm2) Masonry Strength (N/mm2) Specimen 1 2 3 4 5 6 Mean Value (N/mm )
2

Flexure 4.7 13.2 17.6

Compression 16.3

7.9 6.6 8.4 5.6 7.6 6.2 7.1 5.6

Characteristic Compressive Strength (N/mm2)

Table B3: Porotherm 190

Mean Mortar Strength (N/mm2) Mean Unit Strength (N/mm )
2

Flexure 3.7 12.1 15.0 Masonry Strength (N/mm2)

Compression 14.0

Normalised Unit Strength (N/mm2) Specimen 1 2 3 4 5 6 Mean Value (N/mm2) Characteristic Compressive Strength (N/mm )
2

5.1 5.4 5.4 5.4 5.2 5.8 5.4 4.5

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Table B4: Porotherm 365 (T12)

Mean Mortar Strength (N/mm2) Mean Unit Strength (N/mm2) Normalised Unit Strength (N/mm2) Masonry Strength (N/mm2) Specimen 1 2 3 4 5 6 Mean Value (N/mm )
2

Flexure 2.8 10.5 12.1

Compression 9.5

3.6 3.9 4.6 5.0 5.5 4.9 4.6 3.6

Characteristic Compressive Strength (N/mm2)

Annex C: Masonry Flexural Strength  The tests were carried out at CERAM according to BS EN 1052-2. Table C1: Porotherm 365 (T12) Tested with Parge Coat in Tension
Flexural Strengths (N/mm2) Parallel Specimen 1 2 3 4 5 Mean Value (N/mm2) 0.24 0.28 0.23 0.14 0.21 0.22 Specimen 1 2 3 4 5 Mean Value (N/mm2) 0.11 0.10 0.13 0.12 0.12 0.12 Normal

Table C2: Porotherm 100 Tested with Parge Coat in Tension

Flexural Strengths (N/mm2) Parallel Specimen 1 2 3 4 5 Mean Value (N/mm2) 1.44 1.39 1.54 1.46 0.96 1.36 Specimen 1 2 3 4 5 Mean Value (N/mm2) 0.46 0.62 0.54 0.48 0.50 0.52 Normal

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Table C3: Porotherm 365 (T12) Tested with Parge Coat in Compression
Flexural Strengths (N/mm2) Parallel Specimen 1 2 3 4 5 Mean Value (N/mm2) 0.16 0.21 0.19 0.12 0.10 0.15 Specimen 1 2 3 4 5 Mean Value (N/mm2) 0.12 0.10 0.12 0.11 0.12 0.12 Normal

Table C4: Porotherm 100 Tested with Parge Coat in Compression

Flexural Strengths (N/mm2) Parallel Specimen 1 2 3 4 5 Mean Value (N/mm2) 0.80 0.78 1.00 0.90 0.88 0.87 Specimen 1 2 3 4 5 Mean Value (N/mm2) 0.51 0.44 0.39 0.34 0.41 0.42 Normal

Annex D: Figure D1
Shear Strength versus pre-compression of 100mm Porotherm Block 0.80

Shear Strength (N/mm2)

0.70 0.60 0.50 0.40 0.30 0.20 0.10 0.00 0 0.1 0.2 0.3 0.4 0.5 0.6 Pre-compression (N/mm2)

Key:

Mean Shear Strength  Characteristic Shear Strength

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Figure D2
Shear Strength versus pre-compression of 365mm Porotherm Block 0.40 0.35 Shear Strength (N/mm2) 0.30 0.25 0.20 0.15 0.10 0.05 0.00 0 0.1 0.2 0.3 0.4
2

0.5

0.6

Pre-compression (N/mm )

Figure D3
Shear Strength versus pre-compression of 100mm with DPC 0.30 0.25 Shear Strength (N/mm2) 0.20 0.15 0.10 0.05 0.00 0 0.1 0.2 0.3 0.4
2

0.5

0.6

Pre-compression (N/mm )

Figure D4
Shear Strength versus pre-compression of 365mm blocks with DPC 0.18 0.16 Shear Strength (N/mm2) 0.14 0.12 0.10 0.08 0.06 0.04 0.02 0.00 0 0.1 0.2 0.3 0.4
2

0.5

0.6

Pre-compression (N/mm )

Key:

Mean Shear Strength  Characteristic Shear Strength

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Annex E: Lintels  Individual results for the cavity lintels tested are given in Tables E1 to E3.
Clear span (mm) 1000 Mean 2300 Mean

Table E1: Performance of Lintels on 100mm blocks

Max Load Shear (kN) 51.87 51.40 49.37 50.88 59.71 52.73 61.61 58.02 Localised buckling of lintel. Face spalled off shoulder block. Mode of Failure Lintel buckled. Face of blocks spalled. Max Load Flex (kN) 62.78 52.14 56.33 57.08 47.14 35.56 33.14 38.61 Central buckling of lintel. Some spalling of shoulder block. Mode of Failure Central buckling of lintel. Some spalling of shoulder block.

Clear span (mm) 8800 Mean 2300 Mean

Table E2: Performance of lintels on 140mm blocks

Max Load Shear (kN) 49.45 37.41 51.81 46.22 63.00 59.78 69.15 63.98 Localised buckling of lintel. Face spalled off shoulder block. Mode of Failure Lintel buckled. Face of blocks spalled. Max Load Flex (kN) 41.76 41.80 45.28 42.95 54.30 48.85 44.02 49.06 Central buckling of lintel. Some spalling of shoulder block. Mode of Failure Central buckling of lintel. Some spalling of shoulder block.

Clear span (mm) 1080 Mean 2190 Mean

Table E3: Performance of lintels on 190mm blocks

Max Load Shear (kN) 58.94 50.06 68.38 59.13 44.94 48.06 42.19 45.06 Localised buckling of lintel. Face spalled off shoulder block. Mode of Failure Lintel buckled. Face of blocks spalled. Max Load Flex (kN) 55.21 52.50 61.60 56.44 63.39 58.11 62.61 61.37 Central buckling of lintel. Some spalling of shoulder block. Mode of Failure Central buckling of lintel. Some spalling of shoulder block.

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Safe Working Loads for Keystone Lintels for Cavity Walls with a Porotherm Masonry Inner Leaf (100mm, 140mm and 190mm blockwork)
Manufactured Length (mm) Manufactured Length (mm) Lintel Height (mm) Safe Working Load (Total UDL.kN) Inner Leaf Outer Leaf 18 5 25 8 20 9 35 12 600 1800 150 1950 2400 150 2550 2700 150 2850 3000 220

 he failure loads for the two part lintels tested with the 365mm Porotherm masonry are given in Tables T E4 and E5.
Test Flexure Shear

Table E4: Performance of 1200mm Lintel

Lintel No 1 70.5 51.1 2 70.6 57.2 3 70.8 64.0

Test Flexure Shear

Table E5: Failure Loads for 2550mm Lintel

Lintel No 1 81.5 67.1 2 109.4 66.1 3 109.4 67.6

Safe Working Loads for Keystone Lintels for 365mm Porotherm Masonry (two part lintels) 
Manufactured Length (mm) Manufactured Length (mm) Lintel Height (mm) Safe Working Load (Total UDL.kN) Inner Leaf Outer Leaf 18 18 25 25 20 20 35 35 600 1800 150 1950 2400 150 2550 2700 150 2850 3000 220

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Annex F: Fixings  ischer Fixing Systems carried all tests out using a calibrated Hydrajaws 2000 Tensile Meter in F accordance with CFA (Construction Fixings Association) guidelines. All tests were carried out on Porotherm blocks of 190mm and 365mm thickness (six in each case). These are representative of the core range of Porotherm blocks in terms of fixing penetration into the perforated structure. F.1 Light Duty Fixing

 For an 8mm dia., drilled hole and 50mm embedment length the following Safe Working Loads based upon a safety factor of 7 are recommended. This global safety factor is relatively conservative for masonry and is used for all nylon plug type fixings.
Safe Working Load (kN) Block Thickness (mm) 190 0.10 365 0.13

 hese may be compared with recommended loads for other substate materials viz. Concrete T 0.6kN, solid brick 0.3 kN, aircrete blocks 0.15 kN. The full experimental results are in Tables F1 and F2. NOTE: as an indication a single fixing with a 0.10kN Safe Working Load could be designed to resist the weight of a 40kg mass supported 150mm off the face of the wall and 600mm below the fixing. F.2 Facade Fixing

 For a 10mm dia. drilled hole and a 70mm embedment length, the following Safe Working Loads based upon a safety factor of 7 are recommended. This value of global safety factor is relatively conservative for masonry and is used for all nylon plug type fixings.
Safe Working Load (kN) Block Thickness (mm) 190 0.17 365 0.16

The full experimental results are in Tables F3 and F4.  F.3 Light-Medium Duty Fixing

 For a 10mm drilled hole and an embedment length of 50mm the following Safe Working Loads based upon a safety factor of 7 are recommended. This value of global safety factor is relatively conservative for masonry and is used for all nylon plug type fixings.
Safe Working Load (kN) Block Thickness (mm) 190 0.15 365 0.17

The full experimental results are in Tables F5 and F6. 

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F.4

Heavy Duty Fixing

 For a 16mm x 85mm plastic sleeve and a M8 stud the following Safe Working Loads based upon a safety factor of 4 are recommended. This value of global safety is used for resin based fixings. It is consistent with the ranges for similar components given in EC6.
Safe Working Load (kN) Block Thickness (mm) 190 1.67 365 1.44

 hese fixings are used more generally where there is a required Safe Working Load of 1.4kN, T clearly this guideline may be applied to Porotherm masonry. The full experimental results are given in Tables F7 and F8. Note: In the case of fixings with a 50mm embedment into Porotherm 140 and 190 blocks, the values for 100mm blocks may be used. For longer embedment lengths the manufacturers advice should be sought. Table F1: Light Duty Fixing, 190mm Porotherm Block
Test No 1 2 3 4 5 6 Mean Load in kN 1.0 0.9 0.5 0.7 0.5 0.5 0.68 Mode of Failure Block End 1st Tensile Slip Block End 1st Tensile Slip Mid Block 1st Tensile Slip Mid Block 1st Tensile Slip Mid Block 1st Tensile Slip Mid Block 1st Tensile Slip

Using a global safety factor of 7, safe working load in tension = 0.10kN  Table F2: Light Duty Fixing, 365mm Porotherm Block
Test No 1 2 3 4 5 6 Mean Load in kN 1.0 0.7 1.5 0.7 1.0 0.6 0.91 Mode of Failure Block End 1st Tensile Slip Block End 1st Tensile Slip Mid Block 1st Tensile Slip Mid Block 1st Tensile Slip Mid Block 1st Tensile Slip Mid Block 1st Tensile Slip

Using a global safety factor of 7, safe working load in tension = 0.13kN 

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Table F3: Facade Fixing, 190mm Porotherm Block

Test No 1 2 3 4 5 6 Mean Load in kN 1.1 0.5 1.8 1.5 1.5 1.0 1.23 Mode of Failure Block End 1st Tensile Slip Block Mid Wall 1st Tensile Slip Block Mid Wall 1st Tensile Slip Block Mid Wall 1st Tensile Slip Block Mid Wall 1st Tensile Slip Block Mid Wall 1st Tensile Slip

Using a global safety factor of 7, safe working load in tension = 0.17kN  Table F4: Facade Fixing, 365mm Porotherm Block
Test No 1 2 3 4 5 6 Mean Load in kN 1.2 1.3 0.8 1.3 1.1 1.2 1.15 Mode of Failure Block End 1st Tensile Slip Block Mid Wall 1st Tensile Slip Block Mid Wall 1st Tensile Slip Block Mid Wall 1st Tensile Slip Block Mid Wall 1st Tensile Slip Block Mid Wall 1st Tensile Slip

Using a global safety factor of 7, safe working load in tension = 0.16kN  Table F5: Light-Medium Duty Fixing, 190mm Porotherm Block
Test No 1 2 3 4 5 6 Mean Load in kN 1.0 1.4 0.8 1.0 0.9 1.2 1.05 Mode of Failure Block End Substrate Failure Mid Block Substrate Failure Mid Block Substrate Failure Mid Block Substrate Failure Mid Block Substrate Failure Mid Block Substrate Failure

Using a global safety factor of 7, safe working load in tension = 0.15kN 

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Table F6: Light-Medium Duty Fixing, 365mm Porotherm Block

Test No 1 2 3 4 5 6 Mean Load in kN 0.9 1.0 1.2 1.2 1.6 1.6 1.25 Mode of Failure Block End Substrate Failure Mid Block Substrate Failure Mid Block Substrate Failure Mid Block Substrate Failure Mid Block Substrate Failure Mid Block Substrate Failure

Using a global safety factor of 7, safe working load in tension = 0.17kN  Table F7: Heavy Duty Fixing, 190mm Porotherm Block
Test No 1 2 3 4 5 6 Mean Load in kN 6.0 6.1 6.2 7.0 9.9 5.0 6.7 Mode of Failure Block Failure Block Failure Block Failure Block Failure Block Failure Block Failure

Using a global safety factor of 4, safe working load in tension = 1.67kN  Table F8: Heavy Duty Fixing, 365mm Porotherm Block
Test No 1 2 3 4 5 6 Mean Load in kN 4.5 6.0 7.0 5.0 6.0 6.1 5.7 Mode of Failure Block Failure Block Failure Block Failure Block Failure Block Failure Block Failure

Using a global safety factor of 4, safe working load in tension = 1.44kN 

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Annex G: Tension Straps Table G1: Tensile Load Capacity of Horizontal Straps (kN)
Test No 1 2 3 4 5 Mean Porotherm End 10.59 11.10 10.90 11.07 12.15 11.16 Timber End 11.80 12.30 12.33 9.24 10.84 11.30

Table G2: Tensile Load Capacity of Vertical Straps (kN)

Test No 1 2 3 4 5 Mean Porotherm End 8.73 7.77 7.82 8.01 8.77 8.22 Timber End 6.92 6.83 7.76 7.20 7.88 7.32

 Annex H: Figures Figure H1 Flexural Failure of 100mm Porotherm Blockwork 

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Figure H2 Flexural Failure of 365mm Porotherm Blockwork

Figure H3 Localised Failure of Lintel due to Shear Load

Figure H4 Flexural Test on 2.5mm Long, 100mm Wide Lintel

27

Figure H5 Localised Buckling of Lintel Web in Flexural Test

Figure H6 Joist Failure in Bearing Test

Figure H7 Failure of Horizontal Tensile Restraint Strap

28

Annex J Table J1: Test Results on Wall Ties (kN)

Tie No./Mode 1 2 3 4 Mean Tension 1350 1250 1350 1317 Compression 873 938 1065 789 916

Annex K  Exova Warringtonfire Holmesfield Road Warrington WA1 2DS United Kingdom  T: +44 (0) 1925 655 116 F: +44 (0) 1925 655 419 E: warrington@exova.com W: www.exova.com

Testing. Advising. Assuring.

Title: The fire resistance performance of a loadbearing wall assembly, tested in accordance with BS EN 1365-1: 1999. WF Report No: 186546

Prepared for: Wienerberger Ltd: Wienerberger House, Brooks Drive, Cheadle Royal Business Park, Cheadle, Manchester, SK8 3SA

Date: 2nd November 2009 Notified Body No: 0833

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Summary
Objective  To determine the fire resistance performance of a loadbearing wall assembly when tested in accordance with BS EN 1365-1:1999. Sponsor  Wienerberger Ltd, Wienerberger House, Brooks Drive, Cheadle Royal Business Park, Cheadle, Manchester, SK8 3SA. Summary of the The wall assembly has actual overall dimensions of 2600mm high by 3000mm Tested Specimen  with and was formed from 100mm thick Porotherm PTH 100 extruded hollow clay precision blocks bonded with Porotherm Thin-bed mortar. A 10 to 15mm plaster coat was applied to each face of the wall assembly. A load spreader consisting of a steel channel with a sand / cement mortar bed was provided at the base of the assembly.  The test sponsor requested a total applied load of 96kN. This load was applied to the specimen via a steel load spreader and hydraulic rams positioned underneath the assembly. Test Results:  Loadbearing  132 minutes* Capacity Integrity  132 minutes* Insulation  78 minutes * The test duration. The test was discontinued after a period of 132 minutes

Date of Test  15th October 2009

This report may only be reproduced in full. Extracts or abridgements of reports shall not be published without permission of Exova Warringtonfire.

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The guidance given in this document is aimed at showing ways in which appropriately qualified persons can produce structures using Porotherm blocks that have an equivalent level of safety to that when using British Standard Codes of Practice and will therefore meet the requirements of the Building Regulations. CERAM accepts no responsibility for the safety of any building or construction which makes use in whole or in part of this guidance or any liability howsoever arising from the use in whole or in part of this guidance. Queens Road, Penkhull, Stoke-on-Trent, Staffordshire ST4 7LQ, United Kingdom Tel: +44 (0)1782 764428 or +44 (0)845 026 0902 Fax: +44 (0)1782 412331 Email: enquiries@ceram.com Web: www.ceram.com/structures
CERAM IS THE TRADING NAME OF CERAM RESEARCH LIMITED. REGISTERED IN ENGLAND. NO.:1960455. REGISTERED OFFICE AS ABOVE.