Carrie Forsythe said that after she took possession of the south Winnipeg home in September, she started opening up the walls to renovate it.
That was when she discovered her 5,000-square-foot house was a massive mouse nest, she told CBC News.
"All you see is just feces and urine, just puddles and piles," Forsythe said.
"The whole vapour barrier is just filled with this nest."
Forsythe said that for health reasons, she will have to spend at least tens of thousands of dollars to have the mess cleaned up properly.
Every centimetre of drywall has been torn out so that exterminators can remove all the soiled material, and disinfect the building studs and other areas where there was mouse activity.
The house will then have to be reinsulated, and the vapour barrier and drywall will have to be replaced.
"Now I have a shell, which I love, and it will be clean. But someone's got to help me," Forsythe said.
'Years in the making,' says pest control expert
CBC News went on an independent tour of Forsythe's home with Abell Pest Control's Shaun Jeffrey, who said the mouse infestation is the worst he has ever seen.
"Oh my God … this is years, years in the making. This is not new," he observed.
Both Jeffrey and the CBC News crew had to wear respirators while walking around the gutted house.
Jeffrey said the insulation on every level of the house contains mouse feces and urine, and all of it must be removed.
He estimated it would have taken about five years for the infestation to reach this state.
Forsythe said that after she bought the home in May, the previous owner and his family were still living there until she took over possession in September.
Forsythe said she did not get the home inspected before purchasing it, but she did go in with contractors, engineers and architects several times before the handover and no one noticed anything wrong.
Now, she said she will likely have to sue the previous owner.
Previous owner says he didn't know
The previous homeowner told CBC News he did not know anything about a mouse problem, adding that he would have never sold the house if he did.
Forsythe believes he had to have known, but Jeffrey said it is possible the previous owner may not have seen mice in the house, which was constructed with thick walls and thick insulation.
A spokesperson for the Manitoba Real Estate Association says the issue will likely have to be settled in court.
The association is urging all homebuyers to get an inspection done before making their purchases.
Ari Marantz, a certified home inspector in Winnipeg, said a proper inspection might have caught the mouse problem, although it is not normally on the checklist.
A home inspector would have seen red flags suggesting a mouse infestation, and a followup might have identified the problem further, Marantz said.
Marantz said a mouse infestation of this magnitude is rare in Winnipeg, but it occurs more frequently in rural areas.
Forsythe's house is located just outside the Perimeter Highway, on the outskirts of the city.Suggest a correction