The Rapids should have doubled their lead when Deshorn Brown raced through on goal, but with just Perkins to beat his shot clattered off the post and bounced clear.
Perkins kept his side in the game minutes later when Buddle managed to find a path to goal, but the keeper managed to beat away his effort from close range.
After the break, Montreal were inches from equalising as Justin Mapp weaved his way into the area only to see his left-footed shot hit the post.
The misfortune was to cost the visitors as Colorado doubled their lead through Kamani Hill as the midfielder curled the ball past Perkins from the edge of the box.
It got better for the home side minutes later when Shane O'Neill collected a loose ball on the edge of the area and found the top corner with a right-footed shot, after Impact had failed to clear their lines from a corner.
Colorado continued to press and got their fourth goal as Powers got his second of the game when he received the ball inside the box, turned his man and found the bottom corner with a low drive.
Andres Romero got a consolation goal for Montreal, but the home side claimed a thumping win.