Guidelines to Submit Specified Forms (BO Case) to Independent Checking Unit (ICU) by Using Email

    1. General procedures of submitting specified forms (BO Case) to ICU via e-mail

    • a) Applicants can submit the completed and digital signed PDF forms for application under Buildings Ordinance (BO Case) for Alterations and Additions (A&A) Works, Minor Works Control System, Mandatory Building Inspection Scheme (MBIS) and Mandatory Window Inspection Scheme (MWIS), to ICU via emails. The specified forms could be downloaded at Buildings Department’s website (;

      b) Applicant should submit the application to the dedicated e-mail box for receiving email submission
      • Email Submission for A&A works:
        Please attach completed and signed PDF forms for building related plans at the email and send to
      • Email Submission for Minor Works Control System to ICU:
        Please attach completed and signed PDF forms at the email and send to
      • Email Submission for Mandatory Building Inspection Scheme (MBIS), Mandatory Window Inspection Scheme (MWIS) to ICU:
        Please attach completed and signed PDF forms at the email and send to

      c) Applicant should include the following information in the contents of the submission email:
      • (i) The address of the proposed works;
      • (ii) The brief descriptions of the proposed works

      d) Applicants may refer to items 2 and 3 for the requirements of the computer system and digital certificate respectively;

      e) Applicants may refer to items 4 to 6 for the procedure of attaching files to e-forms, removing attached files from e-forms and the requirements on the attached files respectively;

      f) Applicants may refer to items 7 and 8 for the procedure of adding e-signatures on e-forms and removing e-Signature from e-form respectively;

      g) A reply email confirming the receipt of the e-form would be sent to the applicant upon the successful receipt of the submission by ICU.

      h) Applicant should print out the auto-reply email from ICU and bring it together with the "Appendix A of PNAP APP-55 - Payment of Fees on Submission of Plans" for the payment of corresponding A&A submission.
  • 2. System Requirements

  • 3. Requirements of digital certificate

    • The requirements on digital certificate is as follows:
    • (i) Either e-Cert (Organizational) / e-Cert (Personal) issued by a Recognized Certification Authority (currently Hong Kong Post Certification
           Authority or Digi-Sign Certification Services Limited) under the latest provisions of the Electronic Transaction Ordinance (Cap. 553)
    • (ii)   Certificate Standard: X.509v3
    • (iii)  2048-bit RSA key
    • (iv)  In *.p12 file format
  • 4. How to attach files to e-forms?

  • 5. How to remove attached files from e-forms?

  • 6. Requirements on attaching files and file size

    • (i) All files should be attached to the PDF form before the form is digital signed;
      (ii)   Attached files should also be digitally signed, otherwise ICU reserves its right to reject the attached files;
      (iii) The overall size of the email for submitting the PDF form, including attached files and e-Signatures, should not be greater than 25MB.
  • 7. How to add e-Signatures on e-forms?

  • 8. How to remove e-Signatures from PDF forms?