There are a whole bunch of law having to do with the US flag, codified in 4USC:
1. Flag; stripes and stars on.
2. Same; additional stars.
3. Use of flag for advertising purposes; mutilation of flag.
4. Pledge of allegiance to the flag; manner of delivery.
5. Display and use of flag by civilians; codification of
rules and customs; definition.
6. Time and occasions for display.
7. Position and manner of display.
8. Respect for flag.
9. Conduct during hoisting, lowering or passing of flag.
10. Modification of rules and customs by President.
Here’s Section 8, with a few notes in italics from me.
Sec. 8. Respect for flag
No disrespect should be shown to the flag of the United States of America; the flag should not be dipped to any person or thing. Regimental colors, State flags, and organization or institutional flags are to be dipped as a mark of honor.
(a) The flag should never be displayed with the union down, except as a signal of dire distress in instances of extreme danger to life or property.
Is a time of war a period of “dire distress”?
(b) The flag should never touch anything beneath it, such as the ground, the floor, water, or merchandise.
Actually, something I try to teach the child.
(c) The flag should never be carried flat or horizontally, but always aloft and free.
(d) The flag should never be used as wearing apparel, bedding, or drapery. It should never be festooned, drawn back, nor up, in folds, but always allowed to fall free. Bunting of blue, white, and red, always arranged with the blue above, the white in the middle, and the red below, should be used for covering a speaker’s desk, draping the front of the platform, and for decoration in general.
I’ve seen the flag as wearing apparel by people who wear trying to be “patriotic”.
(e) The flag should never be fastened, displayed, used, or stored in such a manner as to permit it to be easily torn, soiled, or damaged in any way.
Elsewhere in the title, there are times to fly it: “The flag should not be displayed on days when the weather is inclement, except when an all weather flag is displayed.”
(f) The flag should never be used as a covering for a ceiling.
(g) The flag should never have placed upon it, nor on any part of it, nor attached to it any mark, insignia, letter, word, figure, design, picture, or drawing of any nature.
(h) The flag should never be used as a receptacle for receiving, holding, carrying, or delivering anything.
(i) The flag should never be used for advertising purposes in any manner whatsoever. It should not be embroidered on such articles as cushions or handkerchiefs and the like, printed or otherwise impressed on paper napkins or boxes or anything that is designed for temporary use and discard. Advertising signs should not be fastened to a staff or halyard from which the flag is flown.
I have occasionally seen company logo flags on the same pole as the US flag.
(j) No part of the flag should ever be used as a costume or athletic uniform. However, a flag patch may be affixed to the uniform of military personnel, firemen, policemen, and members of patriotic organizations. The flag represents a living country and is itself considered a living thing. Therefore, the lapel flag pin being a replica, should be worn on the left lapel near the heart.
I didn’t know that sports teams were “patriotic organizations.
(k) The flag, when it is in such condition that it is no longer a fitting emblem for display, should be destroyed in a dignified way, preferably by burning.
Lots of ragged old flags out there, especially since 9/11/2001. If you don’t want to burn it yourself, take it to the local VFW.