Multiple new home buyers have told me that their builders, some of whom are national builders, have advised them that once the builder has repaired construction defects in the home, including structural and foundation repairs, that they would not have to disclose that in a subsequent sale. 

This is not true!!!!

If the item is listed on the Sellers' Disclosure Notice, whether the builder repaired it or not, you may have to answer "YES" and then you can explain that the builder repaired it. 

For instance, if the house gets wet on the inside because of a drainage issue in the yard and the builder later repairs the cause of that problem, you will have to disclose the following in Section 4:

      PREVIOUS FLOODING

      IMPROPER DRAINAGE

      WATER PENETRATION

You should check "YES" on all of the above and then explain below that water would flow into the house from the back yard during rains until the builder repaired the drainage. 

Not only is this truthful  and required by law, you have now removed the possibility that they can blame or sue you later if the same thing happens to them.  They might have to blame the builder for not repairing it properly.  In this scenario, if you followed the builder's advice, you would be totally on the hook and the builder would be far less responsible than you because of your misrepresentation. 

In short, you should never follow a builder's advice on what and what not to disclose on the Sellers' Disclosure Notice and there is no excuse or exception to disclosure just because or even if a builder makes repairs of something in the house.