Four fire engines and around 25 firefighters were called to a fire at a house on Green Street in Upton Park.
Part of a first floor bedroom was destroyed by fire.
Seven people left the property before the Brigade arrived. One man suffering from smoke inhalation was treated on scene by London Ambulance Service.
It’s believed there were no working smoke alarms in the property. A London Fire Brigade spokesperson said: “This incident shows just how important it is to have working smoke alarms fitted on every level of your home.
“Smoke alarms give the earliest possible warning when a fire starts and we would urge everyone to make sure they have one fitted in every room where a fire can start except kitchens or bathrooms where heat alarms are more appropriate.
"Firefighters also recommend that you have a look at our online Home Fire Safety Checker to make sure there are no hidden hazards in your home.
“The online tool will ask you a series of questions that will help us work out the level of risk in your home, or the home of someone you care for. It only takes a few minutes to get tailored advice to keep yourself and loved ones safe from fire.”
The Brigade was called at 1614 and the incident was over by 1724. Fire crews from Plaistow, East Ham, Stratford and Poplar fire stations were in attendance.
The cause of the fire is accidental and due to the failure of a lithium battery in a power tool that was on charge.