The ACT Brumbies will send a damage bill to Waratahs headquarters this week after coach Michael Cheika’s stormed out of his box at Canberra Stadium and shattered the laminated glass door.

The Waratahs maintain the splintered glass was an "accident" and are waiting to be contacted by stadium officials before deciding if they will pay the $700 price tag for a replacement.

The Brumbies beat the Waratahs 28-23 in a brutal and intense rivalry contest with the tight finish and playing time being chewed up by scrums resulted in damage to the Waratahs' coaching box.

Cheika left the box when the Brumbies won a scrum penalty in the last minute of the game and the glass door shattered when he opened it in frustration.

Several Brumbies members witnessed the incident and it's understood it was also recorded on Canberra Stadium's closed circuit television system.

"It was an accident. We're sure accidents happen from time to time and things get broken every now and then," a Waratahs spokesman said.

"It's up to the stadium to do what they have to do and we'll respond accordingly."

Canberra Stadium officials said it was the first time they had seen a broken glass door to one of the coach's boxes in the Meninga Stand.

Officials will have the door fixed this week before the Brumbies' clash against the Cape Town Stormers on Saturday night.

Because the Brumbies were hosting the game, they are responsible for any damage.

But the Brumbies have already decided they won’t be paying the glazier, instead choosing to pass on the costs to the Waratahs.

The Waratahs trailed by 16 points with 25 minutes to go, but clawed their way back into the contest to be behind by just two points in the dying minutes.

But the Brumbies' scrum, which dominated most of the night, won a crucial penalty in the last minute which allowed Nic White to boot a match-sealing penalty goal.

Cheika said his frustration stemmed from the playing time which was chewed up by scrum set ups and resets.

According to television commentary, it prompted Cheika to confront referee Jaco Pepyer on the sideline.

"There was a lot of intensity and I thought the referee did a pretty good job,’’ Cheika said.

"But I was really disappointed about the scrummage. I won't say my opinion around the rulings, but it's just the amount of time it's taking to set the scrums.

"We went to the referee's meeting at the start of the year and asked if we could bring in a rule that from when the whistle blows, it's 30 seconds and the balls should be in ... nothing happened.

"I think everyone would like that ... especially when you're chasing games. We wasted an unbelievable amount of time on the scrummage.

"The decisions that came off the back of that frustrated me, I admit it for sure."

The only other incident Canberra Stadium staff could remember was when the change rooms were flooded in recent years. But no teams were billed and the incident was deemed an accident.

Coaches getting frustrated in sporting codes is nothing new.

Hawthorn's AFL coach Alastair Clarkson put his fist through a wall in the box at the MCG during a win against Collingwood in 2012.

Cheika is known as a passionate coach and was keen to beat the Brumbies in Canberra to continue the Waratahs' unbeaten win to the season.