The decision to build a new respite centre has been hailed as "a wonderful justice for the children of Ealing" by campaigners.
A new centre will be built following a campaign led by parents upset with a decision to close a residential children's home in the borough.
The new £1.5million centre is set to be constructed alongside the Log Cabin Children's Centre in Northfields following a decision this week.
Earlier this year, Ealing Council voted to close the respite centre Heller House despite a heartfelt rally from more than 50 campaigerners.
Following this week's decision to build a new centre, campaigner Jacqueline Swords, whose son Ciaran used Heller House, said: "I think it's a wonderful day it's justice for the children of Ealing - the children currently travelling to respite out of the borough which should never have happened.
"I feel we have won the day.
"We shouldn't have had to do this. We're very happy and we look forward to working with the council in creating a really excellent respite centre".
Images of what the new centre will look like have not yet been revealed.
At an Ealing Council cabinet meeting on Tuesday (November 16), councillors agreed on the preferred option ahead of building a centre in Haydock Avenue, Northolt, which was the second preferred option, and a site in Broomcroft Avenue in Northolt.
At the meeting, Councillor Binda Rai said the centre would be funded by the sale of Heller House, which has increased in value due to plans for Crossrail.
Subject to engineering surveys the centre, which could include six bedrooms, staff accommodation and a garden play area, is hoped to be ready for 2018.
The council, which will review the findings of the surveys early next year, will invite external providers to bid to run the service on its behalf.
Labour Councillor Binda Rai, cabinet member for children and young people, said: "This is a very exciting solution which will give families high quality, modern respite facilities designed to meet their children’s needs in the borough.
"We are grateful for parents’ involvement throughout the review process and we will continue to welcome their input in the design and creation of this new facility.
"I am also pleased that Heller House can be given a new lease of life by helping families in need of somewhere to live".
A study into Heller House found a number of problems with the condition and structure of the Victorian building, meaning it would cost at least £2.3million to repair it.
The council has agreed the building will be refurbished at a cost of £128,000, to provide temporary accommodation for homeless families.
Speaking after the meeting, Conservative councillor David Millican said: "Huge credit is due to the parents and Ealing Mencap for keeping faith in ensuring that Ealing Council now plans to open a proper residential short break facility for children with disabilities.
"It has been an honour to work closely with the campaigners every step of the way to force the council to U-turn.
"We have forced the Councillors back to the Town Hall time and again until they have finally relented."
Keep up to date with the latest news in west London via the free getwestlondon app.
You can even set it to receive push notifications for all the breaking news in your area.