No, not in this case. :) The -ια is pronounced as a single syllable, therefore there's no need to add the second accent. It is "Πηγαίνετε στα δωμάτιά σας" though... :D So, it is this -ια that's pronounced in one syllable, but not the only one:

1 syllable: παπούτσια, κρεβάτια, ψωμιά, κουτιά (if it's already stressed...), γάντια, μπουκάλια

2 syllables: δωμάτια, κιβώτια, δεμάτια, ιμάτια, πλυντήρια