In plain English
FAR 52.236-28, Preparation of Proposals-Construction, is a solicitation provision prescribed at FAR 36.520, most recently dated Oct 1997. The complete official text is reproduced below, verbatim, from GSA's published FAR source files.
Its text contains no sentence requiring insertion into subcontracts; see the flowdown section below for what that does and does not mean.
Does it flow down to subcontracts?
No flowdown mandate found in the clause text
This is a solicitation provision — it applies to offerors when submitting an offer, not to contract performance, so subcontract flowdown is generally not the operative question for it.
Where it's prescribed
As prescribed in 36.520 , insert the following provision:
Prescribing reference: FAR 36.520.
The official text, verbatim
As prescribed in 36.520 , insert the following provision:
Preparation of Proposals-Construction (Oct 1997)
-
(a) Proposals must be (1) submitted on the forms furnished by the Government or on copies of those forms; and (2) manually signed. The person signing a proposal must initial each erasure or change appearing on any proposal form.
-
(b) The proposal form may require offerors to submit proposed prices for one or more items on various bases, including-
-
(1) Lump sum price;
-
(2) Alternate prices;
-
(3) Units of construction; or
-
(4) Any combination of paragraphs (b)(1) through (b)(3) of this provision.
-
-
(c) If the solicitation requires submission of a proposal on all items, failure to do so may result in the proposal being rejected without further consideration. If a proposal on all items is not required, offerors should insert the words "no proposal" in the space provided for any item on which no price is submitted.
-
(d) Alternate proposals will not be considered unless this solicitation authorizes their submission.
(End of provision)