Leeds architect, the son of James Ellis Braithwaite, a Leeds builder, was born in Leeds on 6 January 1854 and educated at Darley Street WM Day School. Articled to Thomas Ambler, he then entered the office of John Winn & Co, builder, to gain practical experience of the building trade, before returning to Ambler as his assistant. He began his architectural practice in 1880. A member of the MNC, he attended Woodhouse Lane chapel and was involved in its musical life, being an organist and also lecturing on musical topics. He was the architect of some of their Leeds chapels, including Hall Lane MNC (1897-8) and Trinity UM, Tempest Road (1906-7) as well as Victoria Road UMFC (1885-6). He undertook work for the Hepworth family (also members at Woodhouse Lane) and designed the Whitehall Road printimg works for the Leeds UMFC Petty family. From 1891 he was also architect to the Leeds School Board and also architect for the Leeds Industrial Co-operative Society's Albion Street premises. An early exponent of cremation he designed the Lawnswood Crematorium, Leeds, in 1905 which was the first in Great Britain to use gas to cremate the bodies.
Braithwaite was active in both the public and cultural life of Leeds. A Liberal in politics, he was Chairman of the North West Ward Liberal Association, served on the Committee of the YMCA, and was a member of the Leeds Sunday School Union. He was the joint secretary for the Micklefield Colliery Disaster Fund, 1896.