Grenier said he didn't realize how many friends he had until the tragedy struck.
"It's really the thought, that's everything," Grenier said.
Fire gutted the log cabin, known as "The Ponderosa" Sunday afternoon. Grenier and his two children were not home at the time.
"It just destroyed the house," Grenier said.
Grenier went out around noon on Sunday and returned less than two hours later to discover that the home he rented for 23 years was burned beyond repair. The house belongs to Mario and Denyse Plante. Grenier said he believes it will have to be torn down.
More devastating is the loss of his two cats, Dutchess, 16, and Hunter, 14, who were sleeping on a living room chair when Grenier left.
"They just got trapped in this nightmare," Grenier said. "That's what kills you the most. I don't want to think they died suffering like that. It's awful."
The cause of the fire remains undetermined, but fire officials believe an ember from the recently stoked furnace may have come from the chimney and sparked a brush fire that spread to the home.
Hudson Fire Chief Shawn Murray lives in the area and after noticing smoke around 12:30 p.m., drove to the scene and discovered about an acre of brush on fire, according to the Hudson Fire Department. The fire had reached the outside of the cabin and flames were working their way inside, according to a news release.
The chief reported the fire and shortly after requested additional tankers and manpower due to heavy winds, dry conditions and quickly spreading flames.
Mutual aid was received from Nashua, Salem, Windham, Litchfield, Derry, and Tyngsboro, Mass. One mutual aid firefighter was treated at the scene for an abrasion injury, according to the Hudson Fire Department.
If he had been home when the fire ignited Grenier said he would have seen the smoke and been able to stop the brush fire from destroying the residence.
"It was just a matter of starving the fire before it reached the house," Grenier said.
Grenier and his children Brielle, 13, and Paul, who turns 16 on Saturday, managed to save some family photographs and videos from a custom-built bedroom closet. Most of items in the home were destroyed.
Friends have scheduled a fundraiser for 1 p.m. May 12 at the American Legion Post No. 3 on Court Street in Nashua. The event will include a live band and raffles. Tickets are $15 at the door and food donations are requested. Donations to the Ron Grenier and Children Fire Fund can also be made at any Citizens Bank location.