(1)  If a progress payment becomes due and payable, the claimant is entitled to exercise a lien in respect of the unpaid amount over any unfixed plant or materials supplied by the claimant for use in connection with the carrying out of the building work or construction work for the respondent.

(2)  A lien or charge –

(a) over any unfixed plant or materials supplied by the claimant for use in connection with the carrying out of the building work or construction work for the respondent; and

(b) that existed before the date on which the progress payment becomes due or payable –

takes priority over a lien under subsection (1) .

(3)  Subsection (1) does not confer on the claimant any right against a third party who is the owner of the unfixed plant or materials.

(4)  A claimant is not entitled to exercise a lien under subsection (1) in respect of an unpaid amount if the claimant receives the progress payment in respect of the amount.