A charity building a multiple sclerosis therapy centre in Bradley Stoke has won its appeal to build an access route to the site.
South Gloucestershire Council's planning committee had turned down the application after complaints from residents about traffic.
An independent planning inspector has now overturned the decision.
Michael Gelder, chairman of the Moonstone Appeal, said he was "absolutely delighted".
The charity was seeking access via Wheatfield Drive, because it would cost about £1m to have fibre optic cables removed from Bradley Stoke Way.
But residents had expressed concerns it would increase traffic on their cul-de-sac.
The £1.15m centre has already been granted planning permission. The charity had feared it could lose more than £350,000 worth of grants because some are time specific.
Mr Gelder said: "I'm absolutely delighted, particularly for all the sufferers of multiple sclerosis in the greater Bristol area.
"Now we'll be able to offer much larger facilities with improved neurological equipment and treat a lot more people who will be very able to access the site, which has ample parking for them and is designed for wheelchairs which the current centre originally was not."