Here's what experts say could help keep roofs from blowing off in the event of a tornado

'Nobody was hurt, we were lucky that way' Barrhaven residents describe chaotic moments s the tornado swept onto their street. CTV's Natalie van Rooy reports.

As the cleanup continues after a tornado ripped through the south Ottawa suburb of Barrhaven this week, researchers with Western University's Northern Tornadoes Project suggest a $200 hurricane strap could have prevented some of the roof damage to homes in the area.

More than 100 homes were damaged in three areas when a tornado touched down in Barrhaven Thursday afternoon. The damage included roofs ripped off the homes or shingles torn off a building and tossed onto the road.

Researchers with the Northern Tornadoes Project are in Ottawa to assess the damage and determine the strength of the tornado that hit this week.

"We look at the quality of the structural connections, as well," Connell Miller, engineering researcher with the Northern Tornadoes Project, told Newstalk 580 CFRA's at Work with guest host Graham Richardson.

"You'd be surprised how often we go to these events and find that buildings aren't up to code, we find that nails are missing from the roof-to-wall connection, we find that things were not properly installed."

Miller says researchers are pushing the Ontario Government to make changes to the Ontario Building Code to improve the roof-to-wall connections on homes.

"We believe that for around $200 if you use, instead of a series of nails in your roof-to-wall connections, a clip that goes in that holds the roof down onto the wall," Miller said.

"We think that for $200 per house we can protect people's roofs from being ripped off in EF2 tornadoes or less, which is 95 per cent of the tornadoes that we get here in Canada."

Hurricane ties are small metal ties that can hold the structure together.

"It's a series of a few small nails as well as a metal clip that connects the roof to your wall or it’s a series of specialty screws you could use instead," Miller said.

"It adds $200 to the cost of your house and can protect your roof from being ripped off in 95 per cent of tornadoes that Canada gets."

The city of Ottawa says the Ontario Building Code does not "specifically require hurricane ties or straps" on new buildings.

"In Ontario, all municipalities are required, by statute, to enforce the Ontario Building Code (OBC) and are barred from adopting and enforcing local standards or codes above or below what is prescribed in the OBC," John Buck, Building Code Official, told CTV News Ottawa in a statement.

"The OBC does not specifically require hurricane ties or straps for new buildings.”

Western University researchers are also recommending "somewhat longer nails" for the roof decking.

"In combination with hurricane straps (or similar), that should keep a roof on even with an EF2 tornado (assuming built to code)," the Northern Tornadoes Project said on Twitter.

"Getting these and other measures into the building codes is key."

Miller says the Northern Tornadoes Project encourages people to push and advocate for changes to the Ontario Building Code.

"There are areas where the building inspectors aren't allowed to get up on ladders to go inspect roof-to-wall connections," Miller said.

"How do you inspect a roof-to-wall connection for the proper amount of nails if there's no ladder to be able to get the building inspector up there."

The city of Ottawa tells CTV News Ottawa building inspectors are permitted to use ladders for inspections in Ottawa.

The Western University Northern Tornadoes Project was founded in 2017 with the mandate of better detecting tornado occurrence throughout Canada, improve severe and extreme weather understanding and prediction and mitigate against harm to people and property.