^hi sis. i read the relevant clauses, please see quotes below:
"SEC. 3. Coverage. – This Act applies to all domestic workers
employed and working within the country.
SEC. 4. Definition of Terms. – As used in this Act, the term:
...
(d) Domestic worker or “Kasambahay” refers to any person engaged in domestic work
within an employment relationship such as, but not limited to, the following: general househelp, nursemaid or “yaya”, cook, gardener, or laundry person,
but shall exclude any person who performs domestic work
only occasionally or sporadically and not on an occupational basis."
my interpretation (hehe):
If you directly employ a person (not thru a cleaning service) to clean your house on a weekly basis and not on an occupational basis, she is
not covered by this law.

Because even though you are the direct employer, the definition of "domestic worker" covered by this law does not apply to her because the person performs domestic work
occasionally and
not on occupational basis.
Even though the term "occasionally" has not been clearly defined, i think it's good enough to serve as a counter-argument so as to exclude your "weekly helper" from this law.

but it's better to hear a lawyer's interpretation...
any lawyers here?? tama ba ang interpretation ko? hehe.
to GT lawyers: Would a cleaner (directly employed, not thru a cleaning agency) who performs domestic work on a
weekly basis be considered on
occasional basis thus excluding that person from this law? hindi kasi clearly defined yung "occasional"...