ICS 91.060.50  
 
Reference number  
RS 462: 2021  
© RSB 2021  
  
 RWANDA 
STANDARD  DRS 
462 
 
1st edition  
2021 -02-dd 
 
Windows and doors made from rolled mild  
steel sections — Specifications  
 
   
DRS 462: 2021  
©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.rs b.gov.rw  
ePortal: www.portal.rsb.gov.rw   DRS 462: 2021  
iii                ©RSB 2021  - All rights reserved  
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ...................  iv 
1 Scope  ................................ ................................ ................................ ................................ .............  1 
2 Normative references  ................................ ................................ ................................ ...................  1 
3 Terms and definitions  ................................ ................................ ................................ ..................  1 
4 Requirements  ................................ ................................ ................................ ................................  1 
4.1 Material  ................................ ................................ ................................ ................................ ..........  1 
4.2 Dimension and tolerances  ................................ ................................ ................................ ...........  2 
4.3 Construction  ................................ ................................ ................................ ................................ . 2 
4.3.1  Straightness and squareness  ................................ ................................ ................................ ..... 2 
4.3.2  Margins and glazing bars  ................................ ................................ ................................ ............  2 
4.3.3  Joints, corners, and locating and tenon holes  ................................ ................................ ..........  2 
4.3.4  Operation  ................................ ................................ ................................ ................................ ....... 3 
4.3.5  Coupling  ................................ ................................ ................................ ................................ ........  3 
4.4 Ancillary components and fittings  ................................ ................................ .............................  3 
4.4.1  Ancillary components  ................................ ................................ ................................ ..................  3 
4.4.2  Fittings  ................................ ................................ ................................ ................................ ...........  4 
5 Glazing  ................................ ................................ ................................ ................................ ...........  6 
6 Finish  ................................ ................................ ................................ ................................ .............  6 
6.1 Pre-treatment  ................................ ................................ ................................ ................................  6 
6.2 Coating  ................................ ................................ ................................ ................................ ..........  6 
6.3 Painting  ................................ ................................ ................................ ................................ .........  7 
7 Workmanship  ................................ ................................ ................................ ................................  7 
Annex  A (normative)  common dimension of window, door, ventilator and fixed lights  ..................  8 
Annex  B (normative)  sampling and criteria of conformity  ................................ ................................ . 12 
Annex  C (informative)  strength of welded joints  ................................ ................................ ................  14 
Annex  D (informative)  ordering information ................................ ................................ ........................  15 
 DRS 462: 2021  
©RSB 2021  - All rights reserved                  iv 
 Foreword   
Rwanda S tandard 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 462- 2021  was prepared by Technical Committee RSB/TC 047, steel aluminium and related products . 
In the preparation of this standard, reference was made to the following standard  (s): 
1) SANS 727:2003 Windows and doors made from rolled mild steel sections  
2) IS : 1038 - 1983 SPECIFICATION FOR STEEL DOORS, WINDOWS AND AND VENTILATORS  
3) BS 6510:2010 Steel -framed windows and glazed doors – Specification  
The assistance de rived from the above source is hereby acknowledged with thanks.  
Committee membership  
The following organizations were represented on the Technical Committee on Steel aluminium and related 
product s (RSB/TC 047) in the preparation of this standard.  
IPRC Ngoma  
S&H Industries  
RTDA  
SKAT Consulting Rwanda Ltd  
Rwanda  Standards Board  (RSB) – Secretariat  
 DRS 462: 2021  
1                ©RSB 2021  - All rights reserved  
 Windows and doors made from rolled mild steel sections — 
Specifications  
1 Scope   
This standard lays do wn the requirements regarding ma terial, fabrication and finish of steel doors, windows, 
ventilators , and fixed -lights  (sidelights, and fanlights ) manufactured  from rolled ste el sections and their fittings.  
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 referenced document (including any amendments) applies.  
RS EAS 134 Cold rolled steel sections — Specification  
RS ISO 4995 Hot-rolled steel sheet of structural quality  
3 Terms and definitions   
For the purposes of this standard, the follow ing terms and definitions apply  
3.1 
Sub-Dividing Bars  
These are vertical bars in a fixed -light or window or ventilator.  
3.2  
Fixed -Light  
Doors, windows and ventilators where there is no openable shutter.  
3.3  
Ventilator   
The part of a window, sidelight, or fanlight that opens.  
4 Requirements   
4.1 Material  
4.1.1 Strength requirements for Rolled  steel sections for the fabrication of steel doors, windows, ventilators and 
fixed lights shall  be in accordance with table 1   
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 Table 1 — Tensile strength requirements  
Grade of steel  Minimum yield 
stress,  
N/mm2 Ultimate tensile 
strength,  
N/mm2 Minimum elongation as a 
proportion of gauge length,  
% 
210 210 340 24 
250 250 420 22 
360 360 480 20 
 
 
4.1.2 Coupling section to  be used as mullions for coupling the unit side by side and coupling section to couple 
independent units one above the other  shall conform to RS EAS 134 .  
 
4.1.3 Coupling sections manufactured from galvanized steel plate of minimum 1.6 mm thickness may als o be 
used for coupling if agreed to between the Employer and the manufacturer .  
 
4.2 Dimension and tolerances  
4.2.1 The work sizes for overall width and height shall be documented. The size of an assembled frame shall 
be within 2 mm of the  documented work siz e.  
 
4.2.2 The difference between the diagonals of  rectangular frames shall be not more than 4 mm.  
 
Note  commonly dimension of window, door, ventilator and fixed lights are identified in Annex A  
4.3 Construction  
4.3.1  Straightness and squareness  
4.3.1 .1 any deviation from straightness of a member that is intended to be straight shall not exceed 2 mm for 
lengths up to and including 1 500 mm and 3 mm for lengths exceeding 1 500 mm.  
4.3.1.2 The lengths of the diagonals of each frame that is intended to be r ectangular, including the frames of 
opening portions (i.e. ventilators and doors), shall not differ by more than 1 mm in 200 mm.  
4.3.2  Margins and glazing bars  
5.2.1  Margins shall be not more than 2 mm out of parallel.  
5.2.2  When glazing bars are specified by th e purchaser, they shall be not more than 2 mm out of line at tenoned 
joints.  
4.3.3  Joints, corners, and locating and tenon holes  
4.3.3.1 With the exception of joints that are necessitated by the method of fabrication (such as joints at corners  
or at changes of section) no joints, welded or otherwise, shall be allowed.  DRS 462: 2021  
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 4.3.3.2 Corners shall be mitred and  welded.  
4.3.3.3 Subdividing bars and glazing bars shall be tenoned and riveted or welded into the frame. If a  gap at a 
tenoned joint exceeds 1 .0 mm it shall be filled by welding or any other acceptable method and  ground flush on 
the face.  
4.3.3.4 The outer and inner faces of members at joints such as corners shall be flush  within 1 mm except where 
a change in section makes it impracticable.  
4.3.3.5 Locating and tenon holes in the  webs of the sections shall be permitted whether glazing bars are fitted 
or not.  
4.3.3.6 When a unit is tested in accordance with annex C , there shall be no sign of discontinuity in the weld or 
of fracture of the weld d ue to porosity or slag inclusion.  
4.3.4  Operation  
Opening parts shall operate easily and shall not jam or chatter when opened or closed.  
4.3.5  Coupling  
4.3.5.1 A unit shall be so constructed that it can be coupled with any other unit.  
4.3.5.1 When two or more units are coupled, the overall dimensions of the composite arrangement shall not  
exceed the specified dimension  
 
4.4 Ancillary components and fittings  
4.4.1  Ancillary components  
4.4.1.1  Fixing screws  
4.4.1.1.1  Fixing screws shall be M6 countersunk screws  (The outside diameter of  the threads is 6mm ). The length of thread 
shall be at least 12 mm  conforming to the requirements of ISO 10642 .  
4.4.1.1. 2 Screws  shall be supplied with nuts.  
4.4.1.2  Lugs  
4.4.1.2.1 Lugs for fixing windows, doors, and sidelights direct to brickwork or masonry shall be of steel  
(corrugated or flat) and shall have a width of at least 15 mm, a thickness of at least 1,5 mm, and a free  length 
of at least 150 mm  
4.4.1.2.2 Lugs shall be supplied either loose (to be bolted on), or welded or riveted to the  frame.   
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 4.4.1.2.3 When  fixed to the frame, shall be fixed in the following positions and, when supplied loose,  enough 
lugs shall be provided to allow them to be positioned as follows:  
a) Not further than 300 mm from the corners of each side;  
b) spaced  not more than 750 mm apart on any one side.  
4.4.2  Fittings  
4.4.2.1  Hinges  
4.4.2.1.1  Hinges shall be of steel and shall have pins of brass or other corrosion -resistant material.  
4.4.2.1.2 Projecting  hinges for doors and side -hung ventilators shall be so constructed tha t the pivot lies at least 
65 mm  outside the outer face of the frame.  
6.2.1.3  When tested in accordance with Annex C , hinges shall not fail or be  permanently distorted.  
 
4.4.2.2  Locking handle  
4.4.2.2.1 A locking handle shall be of brass or other corrosion -resistant material and, if so specified by the 
purchaser, shall be chromium plated.  
4.4.2.2.2  The handle plate shall be of brass or steel and so constructed that the handle can be mounted or 
removed a fter the window or ventilator has been glazed.  
4.4.2.2.3 A handle for an outward -opening ventilator shall have a two -point nose that shall engage in either 
position with:  
a) a bevelled  brass or other corrosion -resistant material striking plate fitted to the frame, or  
b) an embossed wedge which is part of the window frame.  
4.4.2.2.4 Any bolts or screws used in the assembly of locking handles shall be so securely locked as to prevent 
them from working loose.  
4.4.2.3  Sliding stay  
4.4.2.3.1  A sliding stay assembly, including screws or bolts (or both), shall be of brass or other acceptable  
corrosion -resistant material and, if so specified by the purchaser, shall be chromium plated.  
4.4.2.3.2 The brackets attached to the frame shall be of steel and s hall be of thickness at least 2. 8 mm and 
width at  least 12 mm.  DRS 462: 2021  
5                ©RSB 2021  - All rights reserved  
 4.4.2.3.3 The sliding frictio n device shall be adjustable, the position selected being held by means of  a thumb 
screw that will, when tightened by hand, provide sufficient frictional force to secure the window  in any position 
against an opening force of 50 N applied to the edge of the  ventilator remote from the  hinges.  
4.4.2.3.4 The thumb screw shall be secured effectively to prevent it from being screwed out of the box  
4.4.2.4  Peg stay  
4.4.2.4.1  Peg stays and peg stay screws shall be of brass or other corrosion -resistant material and, if so 
specified by the purchaser, shall be chromium plated.  
4.4.2.4.2 The construction of peg stays shall be such that the ventilator can be locked securely in an acceptable 
manner.  
4.4.2.5  Spring catch  
4.4.2.5.1  A spring catch shall be of brass or other corrosion -resistant material and, if so specified by the 
purchaser, shall be chromium plated.  
4.4.2.5.2  The catch shall have an operating level with eye of inside diamete r at least 16 mm. When the catch is 
in the closed position (and the window open) the spring shall exert an initial force on the catch of 15 ± 5 N.  
4.4.2.5.3 The striking plate of a spring catch shall be of steel of thickness at least 3 mm, and the plate s hall be 
so constructed that the ventilator will lock securely.  
4.4.2.5.4  To ensure proper engagement even when the catch and striking plate are slightly out of alignment, 
the size of the hole in the striking plate, measured in a transverse direction, shall be at least 6 mm larger than 
the diameter of the shaft of the catch .  
4.4.2.6  Sliding bolt  
4.4.2.6.1  A sliding bolt for a door shall be of brass or other corrosion -resistant material and, if so specified by 
the purchaser, shall be chromium plated.  
4.4.2.6.2  If a striking plate is provided, it shall be of either brass or steel.  
4.4.2.6.3  Unless a positive locked position is provided, a friction device to prevent the bolt from moving under 
its own weight shall be incorporated.  
4.4.2.6.4  The force required to  open or to close the bolt shall be 20 -50 N and,  
4.4.2.7  Pivots  
4.4.2.7.1  Pivots for horizontal and vertical pivot -hung ventilators shall be cup pivots and shall be of brass or 
other acceptable corrosion -resistant material.  
4.4.2.7.2  The outside diameter of the pivots shall be at least 40 mm, and the width shall be at least 11 mm.   
©RSB 2021  - All rights reserved                  6 
 4.4.2.7.3  Friction pivots shall be so designed that they can be adjusted to maintain the ventilator in any desired 
position between the fully open and the c losed positions.  
4.4.2.8  Side arms of bottom -hung ventilators  
4.4.2.8.1  Side arms of bottom -hung ventilators shall be of the concealed folding type and shall be made of steel 
or brass or face -mounted remove able fixed stay brackets of steel and shall allow the ven tilators to open to an 
angle of 30 -35°.  
4.4.2.8.2  When tested in accordance with 8.4, side arms or hopper brackets shall show no sign of permanent 
deformation or failure.  
5 Glazing  
5.1 Glass panes shall be at least 3 mm thick  
5.2 All glass panes shall have properly squared corners and straight edges.  
5.3 The sizes of glass panes for doors, windows, ventilators shall be in accordance with the design, drawings.  
5.4 Sheet glass shall be flat, transparent and clear as judged it may, however, possess a light tint, when viewed 
edge -wise.  
5.5 The glass pane sh all be free from any cracks.  
 
6 Finish  
6.1 Pre-treatment  
Methods to pre -treat the surface of the door frames, prior to painting or coating, shall be selected as per ISO 
8504 -1 to provid e a cleaned surface free from rust, dirt, grease, oil, loose scale, weld spatter and any other 
foreign matter. Any other mechanical means such as sand and shot blasting or chemical means that can provide 
the same degree of cleanliness may be applied.  
 
6.2 Coat ing  
8.2.1 After pretreatment of the surface the units shall be dipped in a bath of molten zinc in accordance with the  
requirements laid down in ISO 1461  
8.2.2 The thickness of coating shall be uniform and not less than 0.5 kg/m’.  DRS 462: 2021  
7                ©RSB 2021  - All rights reserved  
 6.3 Painting  
 
6.3.1 All surfaces of the door, windows and ventilator including interior non -visible surfaces, shall receive a 
factory prime coat complying with the provision of ISO 12944 -5. 
 
6.3.2 When specified , top coat and intermediate coats should be on all surfaces of the door frame exposed to 
view as part of paint finishing as per ISO 12944 -5. 
 
6.3.3 If door, windows and ventilator  are not factory finish painted, a compatible coat of finish paint shall be 
applied in the field. The finish paint shall be of a type recommended for use on prime -painted steel. Consult the 
door and frame manufacturer’s literature for description of primer used. The manufacturer of the finish paint 
should verify compatibility with  the primer.  
A red oxide primer so applied as to give a dry film thickness of at least 20 micro meter  
7 Workmanship  
 
Surfaces of frames that can be seen after a unit has been built in shall meet the followings:  
 
a) be smooth level with the faces of the members  
b) show no unsightly hammer or grinding marks.  
c) Irregularities such as burrs or weld fins shall be removed from hidden surfaces but need not be ground 
smooth.  
  
©RSB 2021  - All rights reserved                  8 
 Annex  A 
(normative)  
 
common  dimension of window, door, ventila tor and fixed lights  
Types and overall sizes of steel doors, windows, ventilators  and fixed lights shall be as given in Fig. 2.  
 
Figure 1 Doors  
DRS 462: 2021  
9                ©RSB 2021  - All rights reserved  
  
 
Figure 2 windows  
 
 
 
 
 
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Figure 3 ventilators  
 
DRS 462: 2021  
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Figure 4 fixed lights  
 
©RSB 2021  - All rights reserved                  12 
 Annex  B 
(normative)  
 
sampling and criteria of conformity  
B.1 Sampling  
B.1.1 the doors/windows/ventilators/fixed -lights sh all be sampled in accordance with table 2 
Table 2 sampling of test pieces   
Lot size,  
units  Sample for inspection  Sample for testing  
Sample size,  
units  Acceptance  
number  Sample  size for  
non-destructive  
tests, units  Sample size  
for destructive  
tests, units  
5 – 15 
 2 
 0 3 1 
16 – 25 3 
 
26 – 90 5 
91 – 150 8 
 1 
 5 2 
151 – 280 
 13 
 
281 – 500 20 
 2 
 7 4 
501 – 1 200  32 3 10 6 
 
B-2. CRITERIA FOR CONFORMITY  
B-2.1 the doors/windows/ventilators/fixed -lights selected in the sample  under B -l shall be inspected for  
a) Dimension (annex A)  
b) tolerances  (sub clause 4.2 ),  
c) materials (clause 4 .1),  
d) construction ( 4.3  )  
e) positioning of  holes, fixing screws and lugs ( 4.4),  DRS 462: 2021  
13                ©RSB 2021  - All rights reserved  
  
f) Glazing  (5).  
g) finishing ( 6 ) 
B.2.2 any door/window/ ventilator/fixed -light not satisfying any one or more of the  requirements inspected for 
shall be classified as defective.  
B-2.3 the lot having satisfied the requirements listed in B -2.1 sh all be  inspected for re quireme nts of welded 
joints. For this p urpose a sub -sample  of the size given in Table 1 shall be se lected from the doors/  
windows/ventilators/fixed -lights which have been found non  defective  under B -2.1. The 
doors/windows/ventilators/fixed -lights in the su b-sample  shall be tested according to Annex C   
 
 
 
 
 
  
©RSB 2021  - All rights reserved                  14 
 Annex  C 
(informative)  
 
strength of welded joints  
Strength of welded corners  
C.1.1 cut  out a typical corner of the frame so that the legs are approximately 250 mm long. Grip one leg in a  
vice so that the distance between the jaws of the vice and the inner edge of the free leg is 75 ± 5 mm.   
C.1.2 Twist the free leg through 90° in a plane perpendicular to the axis of the clamped leg.  
C.1.3 Repeat this  procedure in the opposite direction of twist and with t he other leg gripped in the vice and then 
examine  the corner for compliance with the requirements of Annex  C.1.4  (see also figure 9). When relevant, 
repeat the test on a corner of each opening portion of the frame unit.  
C.1.4 There shall be no sign of discontinuity in the weld or of fracture of the weld due to porosity or slag inclusion.  
 
 
 
 
DRS 462: 2021  
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 Annex  D 
(informative)  
 
ordering information  
A-l. The purchaser shall furnish information to the manufacturer or the supplier in regard to the following points:  
a) Type and size of door, window  
b) Whether the units are to be fixed in brick masonry, stone masonry , concrete or steel;  
c) Type of hinges required, for example, whether projecting, non -projecting or friction type;  
d) Details of fittings required including couplings, weather bars, etc;  
e) Whether the mullions and transoms are to be cut to suit masonry or steel work;  
f) Whether removable fly -proof screens are required;  
g) Whether the shutters are required to be opened from inside  or outside;  
h) Type of finish to be provided conforming to the requirements laid down in 8;  
i) Whether wood or metal bead is to be provided in place of putty glazing; and  
j) Any other relevant information.  
 DRS 462: 2021  
 
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