On 11 February 1802, the Heriot Trust Governors approved a large scale plan by Robert Reid and William Sibbald for the development of the area north of Queen Street. This was to be part of the Royalty of the City of Edinburgh, which meant extending the city's northern boundary. The upset price was set at 8 shillings per foot of frontage. Two thirds was to be paid in annual feu duty, the remaining third as purchase price. Heriot Row, facing south to the First New Town, was the first part of this new development.

Robert Reid's major role was to design the elegant palace front blocks of Heriot Row East and West. External features and dimensions - stonework, windows, heights, basement areas - were uniform, harmonious and practical.

Using differently worked stone - smooth ashlar for the upper storeys, rusticated ashlar for the ground floor and rough stone for the basements - reinforced the palace effect.

The main building materials were stone, slate and wood. The stone for the facades came from the local Craigleith quarry. It was sandstone, of consistent structure and very resistant to weathering. It had a high silica content, which made it reflect light. The stonework at the back was of poorer quality. The slates came from the West Highlands. The best ones were from Ballachulish and were used at the front of the roof.  The woods were red pine for structural work and yellow pine for joinery, all imported from the Baltic.

Behind the facades the houses were more diverse, reflecting the taste and pocket of each new owner. End blocks were built as flats, flanking four-storey terraced town houses. The building plots sloped downhill, so that dark storage rooms at the front led to daylit kitchens and gardens at the back. Grander homes had four bays at the front, others three.

Most houses had lofty first floor drawing rooms with plasterwork and white marble fireplaces. Some owners wanted the grandest of current taste, like marble columns in the entrance hall and elaborate moulded ceilings. Despite 200 years of changing taste and house conversions to offices and flats, most of these features have survived and are now protected by the street's A-listed status.

William Sibbald was Superintendant of the Public Works for the City of Edinburgh and also Overseer of Works to the Heriot Trust. He was responsible for laying out the streets, park areas, water and sewer pipes, overcoming legal wrangles and cost challenges. Four of the first owners in the eastern section of Heriot Row complained formally about delays in finishing the street, the mews lane at the back and the access to Hanover Street. Finally in 1805 the Governors authorised the work. They did try to save £107 by laying a five inch water pipe down from George Street to Heriot Row, rather than the seven inch pipe promised when the land was sold.  But under pressure, they authorised an extension.

Most houses in Heriot Row East were finished by 1810. The corner blocks took longer, as they had to be joined on to Howe St and Dundas St, but were complete by 1816. Numbers 1 to 10 were developed by John Hamilton and numbers 11 to 19 by John Thin. The developers in Heriot Row West were Alexander Munro, Archibald Logan, James Easton, Robert Smith, William Wallace, John Sibbald and Peter Dickson.

Completion dates for the entire street were

1804          Numbers 8, 11-14 and 16
1805          Numbers 15, 24-29 and 33-34
1806          Number 9
1807          Numbers 7, 10, 21W, 22-23 and 37
1808          Numbers 1, 4-6, 17, 30, 35-36 and 38
1809          Numbers 20, 21E and 31
1810          Numbers 3, 32, 39-40 and 41E
1812          Numbers 18 and 19
1816          Number 2

Jessie Harden, who lived one street up the hill during the building of Heriot Row, said of it that  'The Row of Houses opposite ours is nearly completed but they are all built just under Lady Blair's Field [which became Queen Street Gardens] so that our situation is still very open for a Town.'

Many of the masons who worked the stone used in building the New Town paid a heavy price, dying from silicosis at relatively young ages. Dust from the high quartz sandstone was particularly dangerous to work. In 1824, Professor Alison of Edinburgh University (himself a resident of Heriot Row) reviewed cases of tuberculosis including silicosis in the capital. He wrote "I have reason to believe that there is hardly an instance of a mason regularly employed in hewing stones in Edinburgh living free from phthisical [wasting] symptoms to the age of 50." 

External features and dimensions - stonework, windows, heights, basement areas - were uniform, harmonious and practical