Howard Street was laid out after 1796 when the Earl of Carlisle sold land to John Wright. Howard was the Earl's family name. Most plots had been built upon by 1826 mostly with two storey brick houses with stone doorways with Tuscan pilasters and heavy straight entablatures. Many of the houses were re-fronted in the Edwardian period and later. No. 73 is fronted with white Portland stone, probably in the 1920s as it is Art Deco in style with an indented eaves cornice. The sash windows have either been renewed at the same time or had glazing bars and handles added to create Art Deco style lights. The building is presently [2013] occupied by Counselling 4 All.

The 1960s Central Library straddles the tunnel on a series of columns and spreads over the line of both roads in the south-west corner of the Square and truncates Camden Street. Square flat-topped flue on roof. The library breaks the square's intended symmetry. However it is neutral to the adjacent Conservation Area. The North Eastern Railway Tynemouth Branch was built in the 1840s. It ran through an east-west tunnel under the south edge of Northumberland Square and Suex Street. As the tunnel is relatively shallow, created by cut-and-cover of the road and the empty sites lining it, it stifled developments along its line. The railway left a gap in the south-west corner of Northumberland Square. This was set out as gardens until engineers were able to build over the railway.

Public library 1965-6 designed by Harry Faulkner Brown of Williamson, Faulkner-Brown & Partners of Newcastle. Lightweight steel-framed glazed building. White plastic laminate where bookshelves abut the windows. Buff brick walls to rear offices. Raised platform of rilled concrete surrounded by granite setts in a diagonal dog-tooth pattern. Roof fascia of corrugated aluminium. Single-storey flat-roofed rectangular building with central square landscaped courtyard. Fully glazed vestibule, with large open-plan adult and children's libraries on one side and a small quiet room (now IT room) on the other side. A meeting and newspaper room, latterly used as exhibition space and a reference library. WCs and staff area to the rear. The entrance is marked by a shallow flagged ramp forming a drawbridge over the granite setts. This is flanked by a pram park on the left-hand side and a cycle park on the right-hand side with slots for seven bicycles. Either side of the glazed double doors are glazed panels with the word LIBRARY in their mid-rail. The central courtyard is fully glazed with indented aluminium fascia. In the centre is a square raised concrete planter surrounded by a pavement of blue bricks. In the north-east corner of the planter is a slender square concrete column on which is set a bronze head of an ancient Roman sculpted by Murray McCheyne.
The library was listed Grade II in 2013.

Houghton's first post office was at No. 3 Sunderland Street from 1824. Around 1918 it moved to No. 48 Newbottle Street. In 1959 a new purpose-built post office was built at No. 12 Newbottle Street costing £35,000. The site had previously been occupied by a telephone exchange. Before that it had housed a shed for the horse-driven ambulance for Dene House Isolation Hospital. The new post office was built with yellow Lumley bricks from Fence Houses Brickworks and had pre-cast concrete floors. It had a concrete strong room and a telegraph room. The roof was layers of plywood, soft wood and felt.

George Wheatley, a Crimean war veteran who lost his right leg aged 19 years, moved his confectionary works from Spennymoor to Houghton. His Mill House sweet factory was in Market Place. In 1879 he was fined for selling sweets that apparently contained yellow leaded paint. He died in 1906 and is buried in Hillside Cemetery. Robert Wheatley took over the sweet factory. His brother John Wheatley was the landlord of the Jolly Farmers Inn which stood opposite the factory (HER 15919). From 1914 John had a sweet shop at No. 51 Newbottle Street. After the First World War George's son William Wheatley opened a sweet factory in the old Salvation Army citadel in Pottery Yard. In 1922 William's son Alfred joined the company. In 1947 the factory moved to the Hawdonside Works on Sunderland Street. In 1958 Alfred's son Keith joined. The whole Wheatley family were enterprising. Robert Wheatley Junior had a fruit, vegetable and confectionary shop on 41 Newbottle Street between 1938 and the 1970s. After the Hawdonside Works closed George Wheatley's grandsons Keith Wheatley and David Wheatley formed a company called Harvian Foods, selling sweets at Pottery Yard. Around 1972 they bought back the Mill House factory. This closed in 1987.

Built around 1865. Three rows of stone miners' cottages for Houghton Pit. There was a shop at the end of South Row. There was a coal house and a toilet in the back yards. They were two up-two down houses with a living room and kitchen on the ground floor and two bedrooms above. Indoor bathrooms weren't fitted until the 1930s, electricity not until the 1950s. The terraces were demolished around 1970. For a while the site was a football pitch. Its now [2007] occupied by Harle Close, Beckwith Close and Fairbairn Drive.
An evaluation was undertaken off Fairbairn Drive in 2020. Two phases of activity were identified, these includes the construction of a post-medieval structural remains and modern masonry, foundation walls and levelling and consolidation deposits associated with a row of stone-built miner’s cottages, the remains of South Row.

Built in 1938-9. In contrast to the existing miners cottages, the new houses had electricity and an indoor bathroom. The kitchen had a pantry. Each house had its own front garden. The area to the rear was open grass. Most of the streets were named after trees (Chestnut Terrace, Laurel Crescent, Hazel Terrace, Beechwood Terrace and Birch Crescent). Coronation Crescent commemorated the coronation of George VI in 1937. The estate was not finished until after the Second World War. Hawthorn Street was added. The Beehive Pub opened next to the estate. A shop was built next to the estate entrance. The council-owned estate was demolished around 2007. Only those houses bought by their tenants now stand.