The man was arrested on the Baltic Sea island of Öland on Monday and is now in psychiatric care. Three children were in the house when the fire started, one of whom managed to escape and call the authorities.
The man appeared in Södertörn District Court at 1pm on Thursday and admitted to all of the charges, according to the Aftonbladet daily. He is reported to have had bandaged wrists.
The fire was first reported around 2.30am on Sunday and the house was engulfed in flames when emergency services arrived. Two bodies were found inside.
The holiday home has been rented by the man for the last two and half years and was located on a lot that includes a larger house.
“He’s been here about every other weekend, when he had his children,” the property owner told the TT news agency at the time.
However, the property owner, who wasn’t home at the time of the fire, refused to release any more details about the man.
Dalarö lies in Haninge municipality in southern Stockholm and is a popular summer holiday destination for Stockholm residents with a large number of wooden holiday homes on the 168 hectare island.