ICS 91.100.30  
 
Reference number  
DRS  260: 201 4 
© RSB 2021  
  
 RWANDA 
STANDARD  DRS  
260  
 
Second  edition  
2014-07-08 
Reaffirmed 2021 -mm-dd 
Concrete roofing tiles — Specification  
 
   
DRS 260: 201 4 
©RSB 2021 - All rights reserved                  ii 
 In order to match with technological development and to keep continuous progress in industries, 
standards are subject to periodic review. Users shall ascertain that they are in possession of the latest 
edition  
 
 
 
 
 
 
 
 
© RSB 2021  
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized 
in any form or by any means, electronic or mechanical, including photocopying and microfilm, without 
prior written permission from R SB. 
Requests for permission to reprodu ce this document should be addressed to : 
Rwanda Standards  Board  
P.O Box 7099 Kigali -Rwanda  
KK 15 Rd, 49  
Tel. +250 788303492  
Toll Free: 3250  
E-mail: info@rsb.gov.rw  
Website: www.rsb.gov.rw  
ePortal: www.portal.rsb.gov.rw   DRS 260: 201 4 
iii                ©RSB 2021  - All rights reserved  
 Contents  Page 
1 Scope  ................................ ................................ ................................ ................................ .............  1 
2 Normative references  ................................ ................................ ................................ ...................  1 
3 Terms and definitions  ................................ ................................ ................................ ..................  1 
4 Symbols  ................................ ................................ ................................ ................................ .........  3 
5 Requirements  ................................ ................................ ................................ ................................  4 
6 Compliance and sampling  ................................ ................................ ................................ ...........  8 
7 Methods of test  ................................ ................................ ................................ .............................  9 
8 Marking, labelling and packaging  ................................ ................................ ...............................  9 
Annex  A (normative)  Concrete roofing tiles -Method of test  ................................ ..............................  10 
 DRS 260: 201 4 
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 Foreword   
Rwanda Standard s are prepared  by Technical Committees and approved by R wanda Standards Board (RSB) 
Board  of Directors in  accordance with the procedures of RSB, in compliance with Annex 3 of the WTO/TBT 
agreement on the preparation, adoption and application of standards.  
The main task of technical committees is to prepare national standards.  Final Draft Rwanda S tandards adopted 
by Technical committ ees are ratifie d by me mbers of RSB Board of Director s for publication and gazettment as 
Rwanda Standards.  
DRS 260 was prepared by Technical Committee RSB/TC 009, Building materials  and c ivil engineering . 
In the preparation of this standard, reference was made to the following standard  (s): 
1) SANS 542:2020 , Concrete roofing tiles   
2) ASTM C1492 − 03 ( 2016 ) Standard Specification for Concrete Roof Tile  
The assistance de rived from the above source is hereby acknowledged with thanks.  
Committee membership  
The following organiz ations were represente d on the Technical Committee on Building materials  and c ivil 
engineering  (RSB/TC 009) in the preparation of this standard.  
Bridge to Prosperity  
City of Kigali  
MASS Design  
NPD  Ltd 
Rwanda Housing Authority (RHA)  
Rwanda Public Procurement Authority (RPPA)  
Standards for Sustainability (SFS)  
University of Rwanda - College of Science and Technology (UR - CST)  
Rwanda  Standards Board  (RSB) – Secretariat  
  DRS 260:  2014 
1                ©RSB 2021  - All rights reserved  
 Concrete roofing tiles — Specification  
1 Scope   
This Draft Rwanda Standard covers concrete roofing tiles of plain and interlocking types  made from lightweigh t 
or normal weight aggregates or both .  
This standard covers concrete roofing tiles intended for the use as roof covering where durability and 
appearance are required to provide a weather -resistant surface of specified design.  
2 Normative references   
The following documents are referred to in the text in such a way that some or all of  their content constitutes 
requirements of this document.  For dated references, only the edition  cited applies. For undated references, the 
latest edition of the reference d document (including any amendments) applies.  
RS EAS 18 -1, Cement — Part 1 : Composition, specification and conformity criteria for common cements.  
RS 373 , Aggregates for concrete  — Specification  
3 Terms and definitions   
For the purposes of this standard, the follow ing terms and definitions apply.  
3.1  
acceptable  
acceptable to the authority administering this standard or to the parties concluding the purchase contract, as 
relevant  
3.2  
defective   
tile that fails in one or more respects to comply with the  appropriate requirements of the standard  
3.3  
lot  
not less than 500 and not more than 5 000 tiles of the same type, pattern, and dimensions, from one 
manufacturer, submitted at any one time for inspection and testing   
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 3.4  
additive  
product which is add ed in small quantities in proportion to the mass of the cement before or during mixing or 
during an additional mixing operation, causing required modifications to the properties  
3.5  
aggregate  
concrete component consisting of uncrushed or crushed natural  substances (or both) and artificial mineral 
substances with particle sizes and shapes suitable for the production of concrete  
3.6  
average transverse strength  
average value of the transverse strengths of the individual tiles  
3.7  
cement  
hydraulic bind er, i.e. finely ground inorganic materials which, when mixed with water, form a paste which sets, 
by means of hydration and which, after hardening, retains its strength and stability  
3.8  
interlocking tile (IL)  
profiled or flat tile with a system of ribs  or grooves enabling the lateral joining of adjacent tiles in the same 
horizontal row, with the overlapping lock covering the underlapping lock  
3.9  
non-interlocking tile (NL)  
generally flat, cross cambered or longitudinally (or both) cambered tile, which is usually rectangular in shape, 
with or without a featured front edge  
3.10  
pigment  
addition inert to the ingredients of concrete and intended to provide colour to the concr ete  
3.11  
quality control test  
test performed on samples drawn either from continuous production or from a consignment of finished products, 
to establish whether a batch of products conforms to this standard  DRS 260:  2014 
3                ©RSB 2021  - All rights reserved  
 3.12  
regular front edge (RF)  
edge of a tile  (interlocking and non -interlocking) which, by design, has a constant or regularly varying hanging 
length across the width  
3.13  
irregular front edge (IF)  
edge of a tile (interlocking and non -interlocking) which, by design, has an irregular varying hangi ng length across 
the width  
3.14  
batten lugs  
protrusions on the underside of the tile designed to engage over the upper edge of tiling battens  
3.15  
profile  
contour of the top surface of the tile when viewed from the nose end  
3.16  
rise  
vertical dist ance from the underside of the batten lug to the highest point of the surface profile  
3.17  
side lap  
continuous longitudinal overlap of a tile on its neighbour  
4 Symbols  
L1  hanging length of a tile (see figure A.1)  
L2, L3  hanging edge length (see figure A.1)  
Cw   nominal cover width of one tile  
Cwc   cover width closed up value of ten tiles  
Cwd    cover width drawn out value of ten tiles   
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 d    profile depth of a tile (see figure 4)  
Fa  average transverse strength of til es  
Fi    transverse strength of an individual tile  
IL    interlocking  
NL  non-interlocking  
RF  regular front edge  
5 Requirements  
5.1 Materials and Manufacture  
Roofing tiles shall be  manufactured from cementitious materials , water, and mineral aggregates with or without 
the inclusion of other materials.  
5.1.1  Cement  
The cement used in the manufacture of the tiles shall comply with the requirements of RS EAS 18 -1.  
5.1.2  Aggregate    
Aggregates shall consist of natural sand; crushed or uncrushed gravel, stone, or rock; or a combination of any 
of these (see RS 373 ).  
5.1.3  Water  
Water used in the mixing of the concrete shall be clean and free from impurities that may impair the strength or 
the durability (or both) of the concrete.  
5.2 Hanging length and squareness  
5.2.1  The tile hanging length shall be declared in the manufacturer’s technical specification. For tiles with a 
regular front edge, the values of L1 shall be within ± 4 mm  of the manu facturer’s declared value when tested 
according to A.1.  
5.2.2  The squareness for tiles with a nominally constant hanging length, when tested in accordance with A.1, 
shall be calculated as the difference between values L2 and L3, and shall be not greater t han 4 mm.  
NOTE  Some tiles are designed, for example for aesthetic reasons, with an irregular front edge (IF). In these cases, the 
test method and requirements do not apply.  DRS 260:  2014 
5                ©RSB 2021  - All rights reserved  
 5.3 Cover width  
5.3.1  General  
The stated cover width Cw shall be declared in the manufactu rer’s technical specification.  
NOTE  Some tiles are designed, for example for aesthetic reasons, with a random cover width. In these cases, the 
requirements specified in 5.3 do not apply.  
5.3.2  Interlocking tiles  
When tiles are tested in accordance with A.2.1,  the average cover width shall be within ± 5 mm of the 
manufacturer’s declared value.  
5.3.3  Non-interlocking tiles  
When tiles are tested in accordance with A.2.2, the average cover width shall be within ± 3 mm of the 
manufacturer’s declared value.  
5.4 Flatness  
When tiles are tested in accordance with A.3, the gap between any desired contact point and the flat surface 
shall not exceed 3 mm.  
NOTE  For some tile patterns, the test method and the requirements in 4.4 are not suitable and do not apply, for 
example:  
a) the tiles are designed to have less than four desired contact points to a flat surface; or  
b) the tiles are designed to be irregular, for example, for aesthetic reasons.  
5.5 Mass  
The mass of tiles shall be declared in the manufacturer’s technical specification. When tiles are tested in 
accordance with Annex A, the average mass shall be:  
a) manufacturer’s declared mass ± 0.2 kg for tiles with a declared mass not exceeding 2 kg; and  
b) manufacturer’s declared mass ± 10 % for tiles with a declared mass greater than 2 kg.  
5.6 Fixing holes (where provided)  
5.6.1  Fixing holes shall be of an acceptable diameter and shall be positioned within 14 mm - 20 mm of the 
batten lug(s).   
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 5.6.2  Plain tile s shall have two fixing holes, the centre of each hole being not less than 25 mm and not more 
than 45 mm from the adjacent side of the tile.  
5.6.3  Profiled interlocking tiles shall have at least one fixing hole that is as close as practicable to the 
longi tudinal centre line of the tile.  
NOTE  It is important that fixing holes be arranged so that a permanent connection between the tiles and the batten 
can be achieved.  
5.7 Transverse strength  
When tiles are tested in accordance with Annex A, ( Fa) and (Fi) per millimetre of tile width shall be not less than 
the appropriate value given in Table 1.  
Table 1 — Minimum transverse strength (N) per millimetre of tile width  
 Interlocking tiles   
Profiled   Flat  
Average  
Fa  Individual  
Fi  Average  
Fa   Individual  
Fi  
5.00  4.50  4.00   3.50  
5.8 Impermeability  
When tiles are tested in accordance with Annex A, drops of water shall not have formed on the underside of the 
roof tiles and there shall be no trace of dampness on the underside of any of the tiles.  
5.9 Water absorption  
Water absorption, when tested in acco rdance with Annex A shall not exceed 10.5 % for normal weight tiles (with 
density greater than or equal to 2 000 kg/km3); 14.5 % for medium weight tiles (with density between      1 500 
kg/m3 and 2 000 kg/m3) and 18 % for lightweight tiles (with density le ss than 1 500 kg/m3).  
5.10 Colour  
The colour shall be as specified by the purchaser. The exposed surface of each tile shall be reasonably evenly 
coloured.  
5.11 Freedom from surface defects  
Roofing tiles shall be  shaped during manufacturing by mo ulding, pressing,  or extrusion and  shall be acceptably 
free from excrescences, depressions and other defects .  DRS 260:  2014 
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 5.12 Surface coating  
Any surface coating applied to the tiles shall not contain any material which is deleterious to the materials of 
which the tile is made.  
5.13 Types a nd dimensions   
5.13.1  Types  
Tiles shall be of the plain type or the interlocking type, as specified by the purchase r and shall be true to pattern 
and uniform in shape.  
NOTE  1 Various tile patterns are available and the purchaser should consult the catalogues o f the manufacturer in this 
regard.  
NOTE 2  Roofing tiles are generally planar or undulating rectangular shapes available in a variety of cross -sectional areas 
profiles, shapes, sizes, surface textures, and colours as may be specified by the purchaser .  
5.13.2  Dimensions   
5.13.2.1  In the case of interlocking tiles, the size (small, medium A, medium B, or large) shall be as specified 
by the purchaser and shall be measured to the nearest 1 mm (see table 1).  
5.13.2.2  The total variation in dimensions of tiles (lengt h, width, and thickness) shall not be more than ± 5 % 
from the manufacturer’s designated dimensions.  
Table 2 ─ Dimensions of concrete roofing tiles  
Nominal Sizes in 
mm (minimum)  Type   
 Plain    Interlocking  
  Small  Medium A  Medium B  large  
Length  265  380  420  420  430  
Width  165  230  280  330  380  
Thickness  10  10  10  10  25  
Side lap  -  25  25  25  35  
NOTE   Interlocking portion shall have a minimum thickness of 8 mm   
  
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 6 Compliance and sampling  
6.1 Concrete roofing tiles shall be deemed to comply with this standard when the manufacturer can 
demonstrate that a random sample taken from a production batch in accordance with table 2 satisfies each 
quality control test requirement.  
6.2  Batch shall be de emed to comply with the requirements of the standard if, after inspection and testing of 
the sample taken, no defective is found.  
Table 3 — Sample size for quality control purposes  
Tests  Batch size (B)   
B < 10 000   B > 10 000  
Hanging length and 
squareness  3   5  
Cover widtha  ≥ 8   ≥ 8  
Flatness  3   5  
Mass  3   5  
Transverse strength  3   5  
Impermeability  16   16  
Water absorption  3   5  
NOTE  a This test is only performed when requested.    
6.3  If the results of tests undertaken on the first sample are inconclusive, a second sample shall be taken in 
accordance with table 3, and shall comply with the acceptance criteria specified in clause 5 .  
Table 4 — Sample size for quality disputes (retest)  
Batch size  
(B)  Sample size  Acceptance  
(maximum number of  
failures)  
B ≤ 151  3  0  
151 < B ≤ 3 200  13  1  
3 201 ≤ B ≤ 35 000  20  2  
35 001 ≤ B ≤ 500 000  32  3  
B ≥ 500 001  50  5  
 DRS 260:  2014 
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 7 Methods of test  
The following tests are required on concrete roofing tiles:  
a) hanging length and squareness of regular front edge (RF) tiles (see A.1),  
b) cover width (see A.2),  
c) flatness (see A.3),  
d) mass (see A.4),  
e) transverse strength (see A.5),  
f) permeability(see A.6),   
g) dimension and weight (see A.7),and   
h) water absorption.(see A.8)  
8 Marking, labelling and packaging  
8.1 Products  
Concrete roofing tiles complying with this standard shall be legibly and indelibly  marked with the name of the 
manufacturer or trademark or with other means of identification.  
8.2 Documents  
The following particulars shall be indicated clearly on the delivery note or invoice or supplier's certificate, 
supplied with the consignment of concre te roofing tiles:  
a) the name or trade mark or other means of identification of the manufacturer; and  
b) the name and colour of the product.  
 
  
©RSB 2021 - All rights reserved                  10 
 Annex  A 
(normative)  
 
Concrete roofing tiles -Method of test  
A.1 Hanging length and squareness of regular front edge (RF) tiles  
Hang the tile at an angle of 20° - 70° on a steel batten (See figure A.1(a)). After having removed any 
burrs or other irregularities (or both), measure the distance from the top face of the batten to the lower 
front edge of the tile at the sides (See figure  A.1(b)). Record the values L2 and L3 to the nearest 
millimetre and calculate the value of L1 to the nearest millimetre.  
A.2 Cover width  
A.2.1  Interlocking  tiles (IL)  
A.2.1.1   Hang or lay a minimum of ten tiles of the same nominal cover width with their locks fitt ing well, in the 
manner specified by the manufacturer.  
A.2.1.2  Push the tiles together to their minimum coverage, taking care that the interlocking parts of the tiles do 
not lift or disengage. Measure to the nearest millimetre and record the closed up value C wc (See figure A.2 ( a)).  
A.2.1.3  Pull the tiles apart to th eir maximum coverage, taking care that the interlocking parts of the tiles do not 
lift or disengage. Measure to the nearest millimetre and record the drawn -out value C wd (see figure A.2 (b)).   
A.2.1.4   Calculate the average cover width to the nearest 0.1 m m as follows:  
𝑎𝑣𝑒𝑟𝑎𝑔𝑒  𝑐𝑜𝑣𝑒𝑟  𝑤𝑖𝑑𝑡 ℎ=𝐶𝑤𝑑+ 𝐶𝑤𝑐
2𝑛−2 
where 
 𝑛 is the number of tiles used  
A.2.2  Non-inter locking tiles (NL)  
A.2.2.1  Hang or lay a minimum of ten tiles of the same nominal cover width on a batten in the manner 
specified by the manufacturer.  
A.2.2.2  Push the tiles together. Measure, to the nearest millimetre, and record the width of the tiles.  
A.2.2.3  Calculate to 0.1 m m the average cover width.  DRS 260:  2014 
11                ©RSB 2021  - All rights reserved  
 A.3 Flatness  
A.3.1  Place the tile on a flat level surface with the nibs projecting, as shown in figure A.3. Hold the tile down 
to ensure that the head of the tile is in contact with the surface.  
A.3.2   Use a steel bar with a diame ter of 3 mm or 𝐶𝑊
100 mm to the nearest millimetre, whic hever is the greater. 
Check whether any gap between the lower front edge of the tile and the measuring surface at any nominal 
contact point without lifting the tile, is greater than the specified value.  
A.3.3  Record the results for each tile tested.  
A.4 Mass  
Condition the tiles to be tested in their dry state at ambient temperature.  
Weigh each tile to at least the nearest 25 g. Record the values measured and calculate the average mass of 
the tiles in the sample to the nearest 10 g.  
A.5 Transverse strength  
A.5.1  Conditions of tiles  
Store the tiles to be tested at ambient temperature for at least 24 h in such a manner that air is free to circulate 
around all sides of each tile.  
A.5.2  Apparatus  
An apparatus that consists essentially of two supports in the form of self -aligning steel bearers (o f diameter 40 
mm and whose distance apart is adjustable) and another steel bearer (of diameter 40 mm), through which the 
load is applied by suitable means at midspan, along a line parallel to the supports. The length of each bearer 
exceeds the maximum widt h of the tile to be tested.  
A.5.3  Procedure  
A.5.3.1  Measurement of profile depth, d  
If the manufacturer’s declared value of d is less than 20 mm, measure d for each tile in the sample, and calculate 
the average value for the sample (See figure A.4).  
A.5.3.2  Positioning the tile in the machine  
A.5.3.2.1  Place the tile to be tested with the top surface uppermost on the lower bearers of the test machine 
so that the centre line of the hanging length is midway between the two lower bearers (see figure A. 5).   
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 A.5.3.2.2  If the tile is not stable in this position (e.g. the tile rests in or on a water -lock), move the tile in the 
direction that brings the tile hanging nibs nearer to the bearer by a distance specified by the manufacturer to 
ensure stable bearing.  
A.5.3.2.3  The angle of the upper bearer (loading bearer) in relation to the fixed lower bearer, does not exceed 
10°. Use packing pieces with a flat top, as necessary, to achieve this (See figure A.6). The width of the packing 
pieces does not exceed the diamete r of the rounded part of the lower bearers.  
A.5.3.2.4  With plain and flat tiles, place an elastomeric pad between the upper bearer and the tile (see figure 
A.5).  
A.5.3.2.5  With profiled tiles, arrange a contoured packing block between the upper bearer an d the tile (see 
figure A.5). Use the contoured packing block made of hardwood or metal or moulded with plaster, which is 20 
mm ± 1 mm wide. Where the contoured packing block is made of hardwood or metal, place an elastomeric pad 
between the contoured packi ng piece and the tile.  
A.5.3.2.6  The length of the elastomeric pad is at least equal to the width of the tile and is not less than 20 
mm wide and 10 mm ± 5 mm thick with a hardness of (50 ± 10) Shore A.  
A.5.3.2.7  So place the tile that the underlock (if applicable) is not loaded and in such a way that the load can 
be applied centrally on the cover width (see figure A.6).  
NOTE  For quality control purposes, the test may be carried out without the use of the elastomeric pad and contoured packing 
block.  
A.5.3.3  Load application  
Apply the load through the upper bearer at a rate not exceeding 6 500 N/min until failure occurs.  
A.5.4  Recording of test results  
Record the maximum load of each tile to the nearest 10 N. When calculating the total load, include  the weight 
of the packing pieces used on the top surface if they exceed 5 N . 
A.6 Permeability  
A.6.1  Apparatus  
A.6.1.1  The apparatus consists of a rain penetration test rig (see figure A.7) that simulates rainfall on the 
tiles. The test rig consists essentially of a section of a roof frame constructed at a pitch of 30° and of sufficient 
area to allow the test specimens (see A.6.2) to be mounted on it.  
A.6.1.2  The sides and back of the rig are enclosed and if the rig is used in the open, some form of cover is 
needed to protect the roof from wind and rain.  
A.6.1.3  Access to the underside of the roof is provided for the purpose of observation. Illumination should 
also be provided.  DRS 260:  2014 
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 A.6.1.4  A sparge pipe is placed over the top of the roof frame to simulate the rain that would run down  from 
higher courses of a full size roof. To simulate direct rainfall, a suitable spray or set of sprays is so placed over 
the area of the frame that every tile receives an equal volume of water. The flow is monitored by means of flow 
meters. The simulated  rainfall used for the test is 150 mm/h from the sparge pipe and 75 mm/h from the spray. 
The flow rate required from the spray to achieve the simulated rainfall for a given roof area is calculated as 
follows:  
𝑄=1.25×𝐴 
where 
 𝑄 is the flow rate in litres per min (L/min); and  
 𝐴 is the actual roof area, in square metres.  
A.6.1.5  The flow rate from the sparge pipe is double that from the spray.  
A.6.1.6  A tank having a capacity of at least 100 L.  
A.6.1.7  A suitable pump, capable of delivering the required flow rates.  
A.6.2  Test specimens  
Take 16 tiles from the sample. Ensure that the tiles are not damaged in any way.  
A.6.3  Procedure  
A.6.3.1  In the case of interlocking tiles, lay the tiles on the test rig in a 4 × 4 arrangement with a head lap 
of 75 mm. In the case of plain tiles, lay the tiles in a similar arrangement but with a head lap of 65 mm.  
A.6.3.2  Start the flow of water and ensure that the required flow rate is achieved. Stop the flow after 2 h 
and inspect the underside of the tiles.  
A.7 Dimensional tolerance and weight  
A.7.1  Dimension  
The total variation in dimensions of tiles (length, width, and height shall not be more than ± 5 % from the 
manufacturer’s designated dimensions.  
A.7.2  Weight   
The total variation in weight of tiles shall not be more than ± 5 % from the nominal weight specified by the 
supplier.   
©RSB 2021 - All rights reserved                  14 
 A.8 Water absorption  
A.8.1  Apparatus   
Unless specified otherwise in the appropriate annex, the balance used shall be readable and accurate to 0.1 % 
of the smallest specimen tested.  
A.8.2  Test specimens  
A.8.2.1   Unless specified otherwise in the applicable annex, test three specimens in absorption.  
A.8.2.2  Unless specified otherwise in the applicable annex, tests shall be performed on full -sized units or 
specimens saw -cut from full -sized units. Calculated values for absorption and density of reduced -size 
absorption specimens shall be considered as representa tive of the whole unit.  
A.8.2.3  When test specimens are saw -cut from full -sized units, the test specimen shall have an initial weight 
after cutting of no less than 20 % of the initial received weight of the full -sized unit.  
A.8.3  Procedure  
A.8.3.1  Saturation  
A.8.3.1 .1 Immerse the test specimens in water at a temperature of 15 to 27 °C for 24 h - 28 h such that the 
top surfaces of the specimens are no less than 150 mm below the surface of the water. Specimens shall be 
separated from each other and from the bottom of t he immersion tank by at least 3 mm, using wire mesh, 
grating, or other spacers so that not more than 10 % of the surface area of the specimen is in contact with the 
spacer.  
A.8.3.1.2  Weigh the specimens while suspended by a metal wire and completely subme rged in water and 
record Wi (immersed weight). Remove from the water and allow to drain for 60 s ± 5 s by placing them on a 
10mm or coarser wire mesh, removing visible surface water with a damp cloth; weigh and record as Ws 
(saturated weight).  
A.8.3.2  Drying  
Subsequent to saturation, dry all specimens in a ventilated oven at 110 °C ± 5 °C for not less than 24 h and 
until two successive weighings at intervals of 2 h show an increment of loss not greater than 0.2 % of the last 
previously determined weight of the sp ecimen. Record weight of dried specimens as Wd (oven -dry weight).  
A.8.4  Calculations  
Calculate absorption in % as follows:  
𝑊𝑆−𝑊𝑑
𝑊𝑑×100 
where DRS 260:  2014 
15                ©RSB 2021  - All rights reserved  
  𝑊𝑆 is saturated weight of specimen, kg; and  
 𝑊𝑑 is oven -dry weight of specimen, kg  
(a) 
  
 (b)   
 Figure A.1 — Hanging length and squareness of regular front edge (RF) tiles  
 
 
 
  
( 
b 
) 
  
 
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(a) 
 
 
  
 
(b) 
Figure A.2 — Cover width   
 
 
 
 
 
 
 
 
 
Figure A.3 — Flatness  
DRS 260:  2014 
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Figure A.4 — Measurement of profile depth  
 
Figure A.5 — Positioning the flat tile in the machine  
 
 
 
 
 
 
 
 
 
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Figure A.6 — Testing with contoured packing blocks  
 
 
 
 
 
 
 
 
 
 
 
 
 
DRS 260:  2014 
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Rear view sectional side view of the rig  
Figure A.7 — Permeability test rig (Simulated rainfall test)  
 
 
 
 
DRS 260:201 4 
 
Price based on  19 pages  
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