UGANDA STANDARD  
  DUS 1781  
First  Edition  
2017 -mm-dd 
 
 
 Reference number  
DUS 1781: 2017  
© UNBS 2017   
   
Wall fillers — Specification 
 
 
  
 DUS 1781: 2017 
ii © UNBS 2017 – All rights reserved  
 Compliance with this standard does not, of itself confer immunity from legal obligations  
A Uganda Standard does not purport to include all necessary provisions of a contract. Users are 
responsible for its correct application  
© UNBS 2017  
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, including photocopying and microfilm, without prior written 
permission from UNBS. 
Requests for permission to reproduce this document should be addressed to 
The Executive Director 
Uganda National Bureau of Standards 
P.O. Box 6329 
Kampala 
Uganda 
Tel: +256 414 333 250 /1/2/3 
Fax: +256 414 286 123 
E-mail: info@unbs.go.ug  
Web: www.unbs.go.ug  DUS 1781: 2017 
© UNBS 2017  – All rights reserved  iii 
 Foreword 
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Trade, Industry and 
Cooperatives established under Cap 327, of the Laws of Uganda, as amended.  UNBS is mandated to co-
ordinate the elaboration of standards and is  
(a) a member of International Organisation for Standardisation (ISO) and  
(b) a contact point for the WHO/FAO Codex Alimentarius Commission on Food Standards, and  
(c) the National Enquiry Point on TBT Agreement of the World Trade Organisation (WTO). 
The work of preparing Uganda Standards is carried out through Technical Committees. A Technical 
Committee is established to deliberate on standards in a given field or area and consists of key stakeholders 
including government, academia, consumer groups, private sector and other interested parties.  
Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the 
general public for comments. The committee reviews the comments before recommending the draft standards 
for approval and declaration as Uganda Standards by the National Standards Council. 
The committee responsible for this document is Technical Committee UNBS/TC 5, Chemicals and 
Environment  
 UGANDA STANDARD  DUS 1781: 2017  
 
© UNBS 2017  – All rights reserved  1 
 Wall fillers — Specification 
1 Scope  
This Draft Uganda standard specifies the requirements, test and sampling methods for fillers in form of 
powder and paste used on both interior and exterior surfaces for levelling of surface imperfections, filling 
dents, cracks and other uneven surfaces on any wall and partitions like plaster, concrete, ceilings and building 
boards The standard does not apply to sand filling and structural cracks. 
2 Normative references  
The following referenced documents 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. 
DUS ISO 3856-1, Paints and varnishes — Determination of "soluble" metal content — Part 1: Determination 
of lead content — Flame atomic absorption spectrometric method and dithizone spectrophotometric method  
DUS ISO 9117- 1, Paints and varnishes — Drying tests —Part 1: Determination of through-dry state and 
through-dry time 
DUS ISO 24153 —.Random sampling and randomisation procedures  
US 100- 3, Cement — Test methods — Part 3: Determination of setting times and soundness  
US 100- 6, Cement — Test methods — Part 6: Determination of fineness  
US ISO 3251, Paints, varnishes and plastics — Determination of non-volatile matter content  
US ISO 3679, Determination of flash no flash and flash point — Rapid equilibrium closed-cup method  
US ISO 7010 — Graphical symbols safety colours and safety signs — Registered safety 
3 Terms and definitions  
For the purposes of this document, the following terms and definitions apply. 
ISO and IEC maintain terminological databases for use in standardization at the following addresses: 
— ISO Online browsing platform: available at http://www.iso.org/obp  
3.1  
Setting time 
the time taken for the filler to convert itself into cohesive mass which does not yield to specified pressure 
applied after a specified drying time. DUS 1781: 2017  
2 © UNBS 2017  – All rights reserved  
 3.2  
hairline cracks 
fine cracks visible on the surface of a shape whose length can be measured and whose width is less than or 
equal to 0.2 mm, see figure  1 
 
Key 
1 Hairline crack 
2 Surface crazing 
3 Open crack 
Figure 1 — Typical cracks  
3.3 
surface crazing 
network of hairline cracks confined to the surface of the shape, see Figure 1 
3.4 
open crack 
cracks or tears on the surface whose length is more than 10 mm and whose width is more than 0.2 mm 
4 Requirements 
4.1 Description 
4.1.1  Paste 
The material shall be homogeneous paste and shall be free from grit and other visible impurities ready for use. 
4.1.2  Powder 
4.1.2.1 The material shall be cement based  polymer modified  (calcium carbonate and / or gypsum) , 
homogenous, free flowing and fine dry powder.  
4.1.2.2 It shall require addition of water to form a consistent paste before application.  Thorough mixing shall 
be carried out till a smooth, homogenous paste is obtained . 
4.2 O dour  
The material shall not have any objectionable  odour. Also it shall not leave any bad odour after application.  DUS 1781: 2017 
© UNBS 2017  – All rights reserved  3 
 4.3 Surface preparation  
4.3.1 The surface shall be free from dust, oil, grease, debris or loose particles and other contaminants. 
4.3.2 In case of powder moisten the surface before applying the filler. Fine hairline cracks should be 
widened up to a minimum of 0.001m and then filled. 
4.4 Mixing 
4.4.1  Powder 
4.4.1 .1 A clean mixing vessel shall be used 
4.4.2 .2 Mix thoroughly powder and water in the ratio as recommended by the manufacturers. 
Note The powder should be added to water to avoid the formation of lumps. 
4.4.2  Paste 
The product is a ready- to-use product dilution shall not be done 
4.5 Application 
4.5.1 Fill the filler into the crack by spatula, scrapper or knife blade. Fill excess material and tool it by putty 
knife blade pressing against crack so that air voids get filled  
4.5.2 Level the surface with a putty knife/towel or steel float to get smooth & clean surface. 
4.5.3 The paste shall not shrink or chip or crack when setting or drying and shall adhere to the surface to 
form a smooth matt finish  
4.6 Weights and measures 
The fill and volume of the material shall comply with the requirements of the Weights and Measures Act. 
4.7 Specific requirement 
4.7.1 Paste 
The material shall comply with the requirements given in table 1 
Table 1 — wall filler (paste) — quality requirements 
Characteristic  Requirement  Test method  
Flash point, min  30°C  US ISO 3679  
drying  time  30 – 120 minutes  WDUS ISO 9117 -1 
Non-volatile matt er %w/w , min 60 US ISO 3251  
Lead content , ppm, max.  100 DUS ISO 3856 -1 
pH 7 – 9 Annex A  
 
4.7.2  Powder 
The material shall comply with the requirements given in table 2 DUS 1781: 2017  
4 © UNBS 2017  – All rights reserved  
 Table 2 — wall filler (powder) — quality requirements 
Characteristic  Requirement  Test method  
Fineness  %Residue ≤  10%  US 100 -6 
water  content ,% w/w , max  5% Annex B  
Setting time   10 – 30 minutes  US 100 -3  
 
4.8 Stability in storage 
The product shall not deteriorate in any manner and shall comply with the requirements of this specification 
when stored in its original sealed container for a period of one year from the date of manufacture. 
4.9 safety  
The material shall have no adverse effects on the human health and environment when it is used for its 
intended purpose . 
5 Packaging and labelling  
5.1 Packing 
The material in which the product is packaged shall not interact chemically or physically with the product and 
shall be strong enough to protect the product adequately during normal handling, transportation and storage. 
5.2 Labelling 
Each container and each bulk package shall bear in prominent, legible, and indelible marking the information 
required in terms of the Weights and Measures Act, and the following additional information together with 
appropriate safety symbols as specified in US ISO 7010 
a) manufacturer's name and physical address; 
b) name of the product; 
c) net mass of the material when packed; 
d) type of the filler 
e) instructions for use; 
f) precautions; 
g) country of origin; 
h) storage recommendation; 
i) batch number; 
j) month and year of manufacture and 
k) month and year of expiry. DUS 1781: 2017 
© UNBS 2017  – All rights reserved  5 
 6 Sampling 
Samples shall be taken randomly from the factory, market or elsewhere and tested for compliance with the 
requirements of the standard .in accordance with DUS ISO 24153  DUS 1781: 2017  
6 © UNBS 2017  – All rights reserved  
 Annex A 
(normative) 
 
Determination of pH 
A.1 Apparatus and materials 
A.1.1 Beaker, 150- ml 
A.1.2 pH meter with glass calomel electrodes 
A.1.3 Analytical balance 
A.1.4 Glass rod 
A.1.5 Distilled water 
A.2 Procedure 
Weigh 5.00 g ± 0.01 g of the paste. Place it in a 150-ml beaker and add 50 g, freshly boiled, distilled water. 
Mix well by means of a glass rod and cool to 23 ºC ± 2 ºC. Measure the pH with a pH meter using glass 
calomel electrode by carefully following the instructions of the meter. DUS 1781: 2017 
© UNBS 2017  – All rights reserved  7 
 Annex B 
(normative ) 
 
Determination of water content  
B.1 Apparatus 
B.1.1 Drying oven 
B.1.2 Desiccator 
B.1.3 Temperature tolerant evaporating dish 
B.1.4 Analytical balance 
B.1.5 Tongs  
B.2 Procedure 
B.2.1 Place an evaporating dish in the drying oven set at 105 o C ± 5 o C for a minimum of 30 minutes and 
then cool to ambient temperature in a desiccator with the lid closed. After cooling, weigh the dish to the 
nearest 1 mg, W 1. 
B.2.2 Weigh 5.0 ± 0.5 g test specimen in a tared and dried dish, W 2 
B.2.3 Place the dish containing sample in the oven set at 105 o C ± 5 o C till the residue mass becomes 
constant  
B.2.4 Cool in the desiccator, weigh the evaporating dish and contents, W 3.  
B.3 calculation 
Water content, %w/w =
100
1 23
W WWW2  
W1 = mass of the empty dish in grams; 
W2 = mass of the dish containing the sample in grams; 
W3 = mass of the dish containing the dry matter in grams; DUS 1781: 2017  
8 © UNBS 2017  – All rights reserved  
 Bibliography 
[1] EU Regulation (EC) No. 1907/2006 (REACH) 
[2] KS 667:2013, Water-thinned priming paints for wood — Specification 
[3] Is SP 25 (1984): Handbook on Causes and Prevention of Cracks in Building  
[4] I S: 4031-Part 1-1996, Fineness of Cement b y dry sieving 
 DUS 1781: 2017 
© UNBS 2017  – All rights reserved  9 
 Certification marking 
Products that conform to Uganda standards may be marked with Uganda National Bureau of Standards 
(UNBS) Certification Mark shown in the figure below.  
The use of the UNBS Certification Mark is governed by the Standards Act, and the Regulations made 
thereunder. This mark can be used only by those licensed under the certification mark scheme operated by 
the Uganda National Bureau of Standards and in conjunction with the relevant Uganda Standard. The 
presence of this mark on a product or in relation to a product is an assurance that the goods comply with the 
requirements of that standard under a system of supervision, control and testing in accordance with the 
certification mark scheme of the Uganda National Bureau of Standards. UNBS marked products are 
continually checked by UNBS for conformity to that standard.  
Further particulars of the terms and conditions of licensing may be obtained from the Director, Uganda 
National Bureau of Standards.  
 
 DUS 1781 : 2017    
 
ICS 87.040
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© UNBS 2017 – All rights reserved