At 02:03 hours Engine 503 was dispatched to 18317 Chestnut Dr. for an "Investigation". The additional information provided by dispatch was that the caller can see a glow coming from the house next door that is being renovated and that it "looks like a fire". Engine 503 (Lt. Gudaitis, DPO Lt. Redmon, FF B. Campbell and FF Fricke) arrived on scene at 02:09 hours and found an approximately 20 foot x 50 foot single story house with a small fire and smoke visible from the main floor of the house. After a quick walk around of the structure more fire was located on the ceiling of the basement. Engine 503 requested the box be filled for a structure fire at this location and quickly went to work pulling a 1 3/4" attack line from Engine 503 and making an aggressive attack against the fire. The house was currently under renovation and the entire inside was nothing but plywood floors and wall studs, this aided crews in quickly extinguishing the fire as additional units began arriving. Additional units assisted in checking the building for any fire extension and securing utilities. Once determined that no more active fire was present and due to the highly suspicious nature of the fire, crews were pulled from the building to preserve any evidence while awaiting the fire marshal's arrival. All units were placed back into service at 02:46 hours and Engine 503 remained on scene assisting the fire marshal until 04:39 hours.