I received an E-mail from Dawn at RoadTrek, here is the E-mail reponse I received from Dawn:
The difference in interior height has nothing to do with the overall exterior height. The overall exterior height of the units now includes the wineguard antenna, which is now a standard feature, so is included in the overall height measurement. The 210 and 190 are 8'9" overall, including this feature, and the 170 currently is 8'7" with this feature.
The standing height is unchanged for the 190, because the floors are different inside. Yes we do still lower the floors on both units, but it is performed in a different manner in the 210 versus the 190 and 170. In the 210, the floor is produced from fiberglass and is lowered approximately an inch lower than the 190 and 170. These two units have the galley lowered, but because there is not a fiberglass construction on these units, the lowering is a bit less.
The current roof line of the 170 is lower than the 190 and 210, so the overall height is approximately 2" shorter.
If you have any further questions or concerns, please don't hesitate to contact me.
Technical Sales Representative
Roadtrek Motorhomes Inc. (formerly Home & Park Motorhomes)
100 Shirley Avenue
(519) 745-0711 ext. 1166
825-2772 ext. 1166