It's been one year since Edmonton's largest residential fire and police are still trying to find out who sparked the massive blaze in the south end of the city.

The fire started in the early morning hours of July 21, 2007 and destroyed 18 homes and gutted a condo complex under construction. About 76 other homes were damaged.

Last year investigators determined the fire was deliberately set, but no charges have been laid in relation to the blaze.

"We're pretty well at the end as far as momentum goes...but again we have no real hard suspect," said Edmonton Police Arson Unit Detective Garry Cinnamon.

While no one has been brought to justice for causing the blaze, Edmonton fire Chief Randy Wolsey says the fire itself acted as a catalyst for change.

"It became a high attention fire, brought the attention of politicians and code officials alike," said Chief Wolsey.

In May the province made 18 recommendations to improve Alberta's building codes in order to prevent such fires from happening again.

While there have been positive changes, the one year anniversary is flaring up difficult memories for a number of residents whose MacEwan neighbourhood homes were engulfed in flames last summer.

"Somebody is out there, several people I believe, knowing they've caused this and who knows maybe they're laughing maybe they're feeling guilty," said MacEwan resident Michael Hogan.

"We've spent the past year trying to put the pieces back together," said resident Ken Smy.

Smy and a number of other people's homes that were destroyed or damaged in the fire are still in the process of rebuilding.

"We had to wait for the exterior of the home to be repaired and that was quite a reminder until that got done and we still have some interior repairs to be done because our windows were replaced," said Smy.

More to come on CTV News at 6 p.m.