Electric Picnic organisers are warning that it will take "considerably longer" to get to the festival this year.
Traffic on two of the main routes to the event is expected to be much busier as roadworks continue.
Drivers using the M7 from Dublin and M8 from Cork are being advised to give themselves plenty of extra time to travel this weekend.
Elaine O’Sullivan of AA Roadwatch said “First and foremost, make sure you plan ahead for your journey to Electric Picnic and allow yourself plenty of time to get to the festival site. If you are leaving after work on Friday, keep in mind that evening rush hour delays start to pick up a little earlier and you will see increased volumes of commuter traffic from about 2.30pm onwards so factor that into your plans.
"Festival-goers will start to make their way to the site from late morning onwards on Friday, so areas closer to the site will be quite busy.
"If you are heading to the festival via N7/M7 bear in mind that reduced speed limits are in place both ways between J8 Johnstown and J11 M9 as part of ongoing works and this will slow traffic between these junctions.
"If you’re coming from Cork, the M8 is completely closed both ways for works between J13 Mitchelstown South and J14 Fermoy North until 8pm Friday evening so you will have to divert via the Old N8.”