The hosts were the first to make the breakthrough and they did so in the 21st minute.
Oscar Boniek Garcia sent through Will Bruin on goal, and the American forward slotted home with his right foot from close range.
Andre Hainaul came close to doubling Houston's advantage in the 34th minute with a header from Brad Davis's corner, but his attempt was too high.
Both sides had chances to add to the scoreline in the second half, with Luis Silva coming close for Toronto and Macoumba Kandji hitting back for Houston.
Then five minutes from time the visitors restored parity when Terry Dunfield headed home from the centre of Houston's penalty box.
Adam Moffat took an attempt for Houston from distance in the final minute but failed to do anything productive, as this Eastern Conference clash ended in a 1-1 draw.