A woman, believed to be in her 30s, died after being trapped in an upstairs bedroom as the fire tore through the semi-detached property in Harvest Road, Smethwick, early on Saturday.
She was one of three people inside, with the other two - understood to be her mother and father - managing to escape and survive.
A spokesman for West Midlands Fire Service confirmed on Monday that investigations were continuing, with the cause of the blaze yet to be confirmed.
The house remained taped off on Monday, with a handful of yellow flowers near blue West Midlands Police tape stretched across the front garden of the house.
The house was destroyed by the fire and remained charred and blackened, with the windows blown out, while a pile of blackened debris was left on the front garden and drive of the property.
The woman was pulled from the flames by firefighters who found her unconscious in the bedroom but was pronounced dead shortly afterwards, West Midlands Fire Service said.
The other two people inside, aged in their 50s, managed to escape after neighbours raised the alarm at around 4.30am.
They were both taken to hospital after being treated by medics at the scene.
Taxi driver Ashmetullah Faizy called 999 after returning home from work and noticing flames rising from the semi-detached house across the road.
Nineteen firefighters attended the scene, with four crews arriving from West Bromwich, Smethwick, Oldbury and Woodgate fire stations.
In a statement released on Saturday, a spokesman for West Midlands Fire Service said: "Our thoughts are with them and everyone affected by this incident.
"Investigators from West Midlands Fire Service will be working with police colleagues to establish how the fire started."