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WRc plc


This online calculator has been prepared by WRc plc in accordance with the Government's National Calculation Methodology for assessing water efficiency in new dwellings in support of the Building Regulations Approved Document Part G, 2010.

The online calculator is recognised by the following bodies as a useful calculation tool:

  • LABC (Local Authority Building Control)
  • The Building Control Alliance (comprising Association of Building Engineers, Association of Consultant Approved Inspectors, Local Authority Building Control, the Royal Institution of Chartered Surveyors and the Chartered Institute of Building.)
  • WRc-NSF Limited


Neither WRc plc, WRc-NSF Limited, LABC nor the Building Control Alliance accept any liability or responsibility in respect of the National Calculation Methodology, data entered, nor for the results produced by any party using this online calculator or the National Calculation Methodology, nor for any decisions taken based upon those results.

Any support required in the use of the National Calculation Methodology or comments on the Methodology should be sought from or submitted to Communities and Local Government.

Copyright and all other intellectual property rights in the online calculator belong to WRc plc.

Before using the online calculator please ensure that you have read and accept the terms and conditions relating to the use of WRc's website below.

WRc plc


This Agreement sets out the terms and conditions under which WRc plc ('WRc') of Frankland Road, Blagrove, Swindon, Wiltshire, SN5 8YF, UK will provide access to the Service to the Customer. If you do not agree to these terms and conditions please do not access or use this Service. They may be changed at any time, and the Customer is responsible for reviewing them regularly. 'Service' shall mean all information or databases made available by WRc via the internet and belonging to WRc. 'Customer' shall mean the individual or organisation who has signed the related order form or who has indicated acceptance of the Agreement by electronic means.

1 Hours of Service
1.1 The Service will normally be available on a non-guaranteed basis 24 hours a day. WRc reserves the right to temporarily suspend the Service without notice in order to modify or otherwise change or upgrade the Service, or for reasons beyond WRc's control.
2 Warranty
2.1 WRc warrants that all reasonable care has been taken to ensure the accuracy and completeness of the Service, and the quality of the Service. All other warranties with respect to the Service, whether express or implied are excluded to the extent permitted by law, including but not limited to any warranty of freedom from errors or omissions or fitness for any particular purpose.
3 Limitation of Liability
3.1 The Customer accepts that WRc shall in no circumstances be liable to the Customer for any loss or damage arising from any faults or delays in the provision of the Service. Neither shall WRc be liable for any inaccuracies or omissions in the Service or for any decisions taken by the Customer and based on the Service.
3.2 WRc shall not be liable for any indirect or consequential loss (including without limitation loss of profits, goodwill or data) suffered by the Customer and arising in any way in connection with this Agreement, whether or not such loss has been previously discussed by the parties.
3.3 WRc shall not be liable for any loss suffered by the Customer or for any liability of the Customer to any third party unless such damage is caused by the negligence of WRc, its agents or servants.
3.4 WRc's aggregate maximum liability to the Customer in respect of any loss whether such claim arises in contract or in tort shall not exceed a sum equal to the annual subscription fee or, if no annual fee is applicable, to the total fee agreed for the Service.
3.5 The Customer agrees that it is in a better position to foresee and evaluate any loss it may suffer in connection with this Agreement and that the fees payable to WRc for the service have been calculated on the basis of the limitations and exclusions of liability in this Agreement and that the Customer will effect any such insurance as it deems suitable having regard to its particular circumstances and the terms of this Agreement.
4 Restrictions on Use
4.1 WRc grants to the Customer a non-exclusive, non-transferable licence to gain access to the Service and to download the information contained therein for personal use only. No other copying or storage in any retrieval system for any other purpose is permitted without WRc's prior written permission.
4.2 The Service is to be used solely by the Customer and its employees for its own internal business purposes.
4.3 The Customer shall not copy, communicate or disseminate the Service in whole or part to any other party, including any subsidiary, associate or branch of the Customer, by any means whatsoever.
5 Access Control
5.1 WRc shall allocate to the Customer any necessary usernames and/or passwords which control access to the Service. Only those usernames and/or passwords may be used by the Customer to access the Service.
5.2 Where level of usage determines fees payable, or is agreed to be limited to a certain level, the Customer shall pay for all usage which accrues under usernames and passwords allocated to the Customer. Responsibility for limiting usage to a certain level remains with the Customer.
5.3 WRc reserves the right to change the Customer's usernames and/or passwords at any time.
6 Termination
6.1 WRc may terminate this Agreement immediately on written notice if an agreement between the provider of one or more of the database(s) forming part of the Service and WRc is terminated, or in the event of any breach by the Customer of any of the user conditions, including payment and, in particular, those relating to the content of material posted by users.
6.2 Except where the Customer has breached any of the user conditions, WRc shall on termination promptly make a pro rata refund to the Customer of any monies paid by the Customer for the Service for a period which has not expired.
7 Customer Indemnity
7.1 The Customer agrees to hold WRc harmless and fully indemnified against any claims, costs, damages, loss and liabilities arising as a result of any breach of the Customer's obligations under this Agreement or as a result of misuse of the Service.
8 Copyright
8.1 Subject to any third party rights, copyright in the Service and all associated documentation belongs exclusively to WRc and the Customer will acquire no rights thereto. The Customer may only download or reproduce the material for internal use if it maintains all copyright and other notices.
8.2 Customer shall not upload to the Service any content which is in breach of copyright, defamatory, obscene, pornographic or otherwise violates any law and WRc is entitled to delete the same. WRc does not have a policy of reviewing material which appears in open forums and the Customer shall be responsible for any such uploaded material.
9 Links
9.1 WRc is not responsible for the content of any third party website nor liable for any reliance placed by the Customer on any information in any third party web site to which the Service links.
10 Jurisdiction and Law
10.1 This Agreement shall be governed by the laws of England and users are granted access subject to their acceptance of the application of English law to govern matters relating to this web site.
10.2 This Agreement does not affect your statutory rights.


©WRc plc 2022

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