– We rarely see such serious attacks. The smell that greeted us is hard to forget.

Rats that crawled up to the terraced house in Åsane took over the entire house and made it uninhabitable. Rehabbed homes are a recurring problem, says the pest expert.

The owners had been away for a while, and when relatives went to see the house, they raised the alarm.

The damage turned out to be so severe that much of the floor, walls and insulation must be demolished before the house can be rebuilt.

The rats attack resulted in extensive work for the management of Stemmehaugen Borettslag.

– We know that rat and mouse problems are not uncommon in housing associations or other buildings in Bergen. Our housing association experienced this very strongly, says the chairman of the board, Åge Skår.

The cleaning and security work has been going on for almost a year. The insurance company has borne part of the costs, but the housing association itself has had more than NOK 700,000 in expenses to overcome the problem.

Other maintenance measures

– We would have liked to spend this money on other maintenance, but these have been necessary measures, says Skår.

It has been a demanding case for the housing association with 60 townhouses in the center of Åsane.

The rats likely entered from the sewer, crawled along the plumbing system, and then gnawed through cavities and linings in the walls and rooms of the house.

There they have probably had access to food and drink, and have managed to establish themselves.

The rats have bitten into the wood and the electrical system and left feces.

– Rarely large attack

Pest Control Sjur Atterås at Anticimex has had many trips to the housing association in recent months.

– It is very rare that we see such a serious rat attack. The smell that greeted us is hard to forget, says Atterås.

When the house was vacated and pest control agents obtained the building, they were able to take whatever action they deemed necessary.

– At one point we carried out Rema 1000 bags with up to ten rats that we caught in the traps we set in the house, says Atterås.

In addition to damage to the wood and the electrical system, there was odor damage after urine got into the wood.

Now the house is closed.

– No one can be blamed

The chairman of the board, Åge Skår, is concerned that no one can be blamed for the situation.

– There is no doubt that a house has been the source, but the challenge has been that it has been uninhabited for a while. Therefore, the rats have established themselves, says Skår.

– The house is located in a row of neighbors on all sides. Are the neighbors affected?

– The rats have moved to the sides, but the neighbors have not had problems such as the house where the rats entered. There has been a case where rats bit into a hose from a washing machine and some damage to the trim. But here, pest control came out early and stopped the problem before it was allowed to develop, says Skår.

For Stemmehaugen Borettslag, it has been a great learning process to bring the problems of injury to life.

– The most important lesson is to warn early. It is important to prevent rats from establishing themselves and having a chance to breed in the house.

Second, the board has provided information on waste management.

– We have asked for caution when feeding the birds and avoiding trees and shrubs along the walls of the house. Homes should be secured with mouse straps under siding along the foundation wall, but pests can enter homes by climbing shrubs and trees, Skår says.

Electric rat traps

The housing association has now also contracted electric traps for rats found in sewer systems. 400 rats have been caught here this fall.

– We thought it was necessary as a preventive measure. In addition, we have taken special security measures in six of the rows of houses, says Skår.

– Do you now assume that the housing association has control of the situation?

– We are comfortable with the measures that have been implemented. I count the money spent as wellness investments in the housing association. We had to get rid of a problem that was causing concern, says Skår.

Pest control Sjur Atterås in Anticimex says that they have many cases of pest problems in housing associations in Bergen.

– Very often it happens that residents think they hear noise and experience a problem. When we check, there is often nothing, maybe just the sound of a bird on the ceiling. But in this particular case, we have discovered a problem, says Atterås.

General manager Helge Ivarsøy at Cytox, who also conducts pest control in Bergen, believes that rats can cause more damage to houses than before.

It is difficult for him to give a good answer as to whether there are more or less rats than before, but he sees that rats can do more damage to houses now.

Expensive pest infestations

On average, an infestation costs around NOK 60,000, according to figures released by insurance company Frende last year. The worst damage can cost millions.

A recurring problem is the rehabilitated houses.

– The Norwegians are world champions in renewal. But when you rebuild basements and heat insulate where a cold basement used to be, it’s rat-ready too. They look for dry and warm rooms. When you’ve insulated a basement with leaky walls and ceilings, and underfloor heating, the costs of expelling pests go up, says Ivarsøy.

The owner’s duty to control pests such as rats is established and regulated in the Pest Control Regulations.

– In this case, they have also limited the measures that the owners themselves can take. Many ask us about rat poison, but for a long time its use by individuals was prohibited. Various forms of rat traps are currently in use. But the most important thing is that the owners take security measures before getting there, says Ivarsøy.

Bergens Tidende has contacted the relatives of the owners of the house. Refer to the housing association for comment.