Tex. Property Code § 53.124

(a) Except as provided by Subsection (e), for purposes of Section 53.123, the time of inception of a mechanic's lien is the commencement of construction of improvements or delivery of materials to the land on which the improvements are to be located and on which the materials are to be used.

(b) The construction or materials under Subsection (a) must be visible from inspection of the land on which the improvements are being made.

(c) An owner and original contractor may jointly file an affidavit of commencement with the county clerk of the county in which the land is located not later than the 30th day after the date of actual commencement of construction of the improvements or delivery of materials to the land. The affidavit must contain:

(1) the name and address of the owner;

(2) the name and address of each original contractor, known at the time to the owner, that is furnishing labor, service, or materials for the construction of the improvements;

(3) a description, legally sufficient for identification, of the property being improved;

(4) the date the work actually commenced; and

(5) a general description of the improvement.

(d) An affidavit filed in compliance with this section is prima facie evidence of the date of the commencement of the improvement described in the affidavit. The time of inception of a mechanic's lien arising from work described in an affidavit of commencement is the date of commencement of the work stated in the affidavit.

(e) The time of inception of a lien that is created under Section 53.021(3), (4), or (5) is the date of recording of an affidavit of lien under Section 53.052. The priority of a lien claimed by a person entitled to a lien under Section 53.021(3), (4), or (5) with respect to other mechanic's liens is determined by the date of recording. A lien created under Section 53.021(3), (4), or (5) is not valid or enforceable against a grantee or purchaser who acquires an interest in the real property before the time of inception of the lien.