The plans for a new library and archives in Square Road were controversial from the start with many local people in 2011 and 2012 wanting them to remain in Northgate. A protest group called Don't Bulldoze Our Library, supported, it must be said, by Halifax Civic Trust and Halifax Antiquarian Society, was formed and as many as 16,000 people signed a petition against the move away from Northgate to a new library that would be smaller than the existing one and in a less convenient location. But that is history now and, years later, we are able to judge the new library purely on its architecture and functional qualities.

First, this was a complex scheme in which a library for the 21st century had to be squeezed into a space defined by the footprint of the ruins of Square Church and which would respect the heritage not only of the Victorian church but of the other adjacent historic buildings, the Georgian Square Chapel, of handmade brick, the 235ft sandstone steeple of Square Church, the red brick of the Calderdale Industrial Museum and the sandstone backcloth of the Piece Hall walls. The new building had to incorporate the most significant remains of the 1857 church, the steeple and the adjoining transept with its rose window, and include a new pedestrian route from Square Road, via steps and a new entrance to the Piece Hall. Calderdale Council called on Edinburgh architects LDN - the same firm that had masterminded the transformation of the Piece Hall - to design the new library.

They chose a design that is clearly modern, yet blends well with the adjacent historic buildings, is not outrageously innovative and so does not attempt to compete with them. Much of the building's success derives from the inspired choice of cladding material. After considerable experimentation with alternatives, the architects chose an unusual buff-coloured European-style brick, longer than standard British bricks but shallower, manufactured using traditional hand-made techniques, thus giving the brick a more traditional appearance. The architects explained that this brick would be "visually sympathetic but clearly identifiable as new work in relation to the other materials of the historic buildings and structures around the site". It would "be of appropriate scale and quality. While not trying to imitate the stone, the brick has a more horizontal emphasis than standard bricks, which gives a similar proportion to traditional stone walling." It was a master stroke - a modern building clad in a material which is novel, yet somehow familiar, comforting and appropriate for its location.

By visual contrast, large areas of the library on the east and north elevations are glazed and the building utilises an ultra-modern solar shading and ventilation system by the Harrow-based Levolux company to control the effect of daylight entering the building, particularly on the east, Square Road, elevation. Consisting of rectangular and trapezoidal-shaped aluminium fins and external tensioned blinds, the system works to create an energy-efficient, naturally lit and comfortable learning and working environment. The motorised blinds shade a glazed skylight at roof level of 8.9 metres by 4.4 metres.

Internally, the four-storey library comprises a series of bright, attractive and welcoming spaces. The focus is at the centre, where the ground floor entrance leads to an exhibition space and to a series of flights of stairs leading upwards to the first and second floors. En route these stairs "visit" the 19th-century neo-gothic transept of Square Church with its broad arch and rose window, a jaw-dropping surprise for the first-time visitor. The way in which the architects, with great skill, incorporated within the new building these elements of the Victorian church, as well as the 235ft steeple and two more bays of the nave, is perhaps their greatest achievement on this site.

If there has been a criticism of the new library, it is that the overall space is less than at the abandoned library in Northgate. This has caused difficulties for groups and societies which were used to the ample size of the Northgate meeting rooms, for example. But the design incorporates all the required functions of a modern library and archives. The archives and local and family history studies resources are in the lower ground floor, the archives being located in the least well lit part of the building. The ground floor main entrance leads to the exhibition space, children's library, IT suite and visitor centre. The main stairs lead to the first floor where can be found the main collection of adult fiction, large print and talking books, teen fiction and media store. This has been described as a new component to the library service, a development of the music and DVD library, which will latch on to emerging information technology trends. On the second floor are further IT suites, adult non-fiction and reference books and study areas, including bookable study pods.

The designers of our new library and archives have created a remarkable building on a very restricted site, a building which does more than carry out its duties as a functioning library and archives service. It could have imposed itself on the Square Road frontage of historic buildings but instead it respects its elders and blends neatly and carefully with them. The move of the library service from Northgate may not have suited everyone but no one can argue about the quality of the new building, which is a very fair addition to the high calibre of the Halifax townscape.

Architects: LDN, Edinburgh. Main contractor: Graham Construction.

Martin's Mill seems to have been in a state of dereliction for as long as most people can remember. Its condition has been a matter of concern and for some time this six-storey Victorian textile mill has figured on Halifax Civic Trust's list of buildings at risk. The mill, also known as Pellon Lane Mills, is not listed but is named by Calderdale Council as an undesignated heritage asset and while not among the very best of local mills architecturally it stands, imposingly, in a prominent position facing Pellon Lane at its junction with Hanson Lane and has been described as a "landmark" building.

The mill was built for brothers James and Josiah Aked, worsted spinners, probably in the 1860s, although it is now known that the main building was constructed in two parts, the original being at the rear, Richmond Road end of the building. There was also an adjoining warehouse and a large weaving shed. By the 1890's the Aked company was no longer at the mill and from about 1913 the premises were occupied by Martin and Sons, worsted coating manufacturers. In 1958 Martin's sold out to the Tulketh Group, which was responsible for many postwar mill closures in Yorkshire and Lancashire. Subsequently the buildings were used by a variety of concerns, including a joinery company, bath maker and a packaging company. In the 1980's the weaving shed was demolished to make way for a B&Q store, now occupied by The Range. The mill chimney was also much reduced in height. Famously the Plebeians Jazz Club, founded by senior boys from the old Clare Hall School, started life at Martin's Mill before moving after only a few weeks to a cellar in the Upper George Yard.

In 2006, 2007 and again in 2010 plans to convert the mill into apartments were approved by Calderdale Council but none of them materialised. Then in 2017 the Stockton-on-Tees-based Mandale Group came up with the present very successful conversion scheme which was completed by the end of 2018 at a cost of £7 million. Mandale converted five floors of the mill to flats, 12 on each floor, nine with single-bedrooms and three with two-bedrooms. The basement was converted to car parking, with 29 spaces, as well as cycle store and bin storage. Structurally the floors, supported by a central row of cast-iron columns and iron beams, were in such poor condition that the decision was taken to remove all the floors, beams and columns and replace the single row of columns with two rows of steel H columns supporting new concrete floors. This process was begun at the basement and the builders worked up through the building to the roof. The roof itself consisted of two ridged roofs separated by a valley; these were replaced by a single roof. Initially the plain tower at the Richmond Road end of the building was to have been demolished along with a number of decorative features at eaves level, but following a change of mind by Mandale these have been retained.

Inside, the flats are arranged on either side of a central corridor on each floor, and look out towards east and west. They are bright and airy, thanks to the large mill windows. Living rooms and kitchens are open plan. Ceilings have been lowered, creating space to run service pipes and cables. Where possible, historic features have been retained, including bare wall and brick staircases at either end of the building and some impressive Victorian waterworks. A common decor runs through the building, with cream-coloured walls, white window cills, high-quality oak-style doors, grey carpets in public areas and brown carpet tiles in the flats.

After so many years of neglect, Martin's Mill could easily have been demolished. Mandale deserves great credit for taking on a building in exceptionally poor condition and creating 60 new homes in an attractive and homely environment in this very busy part of Halifax.

No one passing by Halifax Borough Market can fail to have noticed the brilliant new colours of the restored market gates. The refurbishment of the gates is part of a much larger renovation of the market - as evidenced by the ground-to-roof scaffolding hiding much of the Market Street facade as we write in April 2019. The market, designed by architects John and Joseph Leeming - who also designed Leeds market - was built between 1891 and 1896, replacing the red-brick New Market of 1790. It was opened by the Duke and Duchess of York, later King George V and Queen Mary in 1896.

The grade 2* market has eight sets of gates for the three entrances on Southgate, three more on Market Street and one each on Albion Street and the Market Arcade leading to Russell Street. They are made of wrought iron and cast iron and the gates vary in style; they are not all the same. The previous paint scheme, dating from no more than 20 years ago, was mostly black with small highlights of red and white Yorkshire roses and has been criticised as "bland and uninspiring". To determine an appropriate colour scheme for the Victorian-era gates Calderdale Council called in Topp and Co., a firm of blacksmiths and architectural metalworkers based at Tholthorpe, York. Topp and Co. took six samples of paint, examined them under low magnification, then at high magnification in halogen and in ultra-violet fluorescent light to define the different paint layers. This process indicated that the gates had been painted 20 times since the 1890s and that the original scheme combined red and crimson with gold leaf. Subsequent repainting included greens, yellows and blues. Following concerns over the weight of the gates and the force need to open and close them Topp's report also recommended a new kind of bottom hinge to reduce the amount of effort needed. The report also highlighted many repairs needed to put right damage caused by wear and vandalism.

The gates were then taken, two sets at a time, to Topp's workshops near York and all paint and rust removed down to bare metal to allow a detailed inspection before repainting. The colour scheme chosen was influenced by the original scheme and the recently redecorated gates at the south entrance of the Piece Hall, of a similar date. The colour palette of crimson, chrome green, sulphur (yellow), dark stone (beige) and white was intended to "pick out details of the gates which have become lost in the monochrome of the black colour scheme". Crimson was used for general framing, green for foliage and flower backgrounds, yellow for flower centres, dark stone for frames and scrolls, and white for flowers.

The market refurbishment programme, of which the restoration of the gates is part, includes repairs to the roof, chimneys and windows and the removal of stalls in the Albany Arcade to create space for pop-up stalls and entertainments. There are also plans to remove the stall "under the clock" and refurbish the clock itself.

The beautifully restored gates, with their rich variety of colours are beacons, welcoming shoppers and visitors to our award-winning market, which is without doubt one of the finest in the country. The restoration has been done honestly, with regard to historical accuracy, science in microscopic detail, and in the best of taste. At a time of recession in retailing, they proclaim Calderdale Council's commitment to the Borough Market and its determination to make it as relevant in the 21st century as it was in the 20th.

2018 was an exceptional year for major developments affecting Halifax's wonderful built heritage and for the first time in many years Halifax Civic Trust decided to make not one, but three awards. They were for the breathtaking transformation of the Piece Hall, the remarkable and beautiful extension to the Square Chapel Arts Centre and the astonishing conversion of the 19th-century Princess Buildings into modern offices for Calderdale Council.

When the rejuvenated Piece Hall reopened on August 1 2017 - Yorkshire Day - nearly 23,000 people came to look. Perhaps they came to see what they had got for the £19.2 million spent on our great Georgian market hall - said to be the most important building in Yorkshire after York Minster - but more likely they came to see what had happened to a building that was dear to them. After all, the Piece Hall has been around a long time, almost two and a half centuries.

The Piece Hall was built in 1779 as a market for 30-yard "pieces" of cloth, woven on hand looms in workers' homes. The hall was open only on Saturdays and for only two hours, between 10am and noon. But even as it was built, this extraordinary building, with its 315 traders' rooms on two and three floors, was heading for obsolescence. For with the new Industrial Revolution, yarn and cloth production moved from workers' cottages to the new textile mills that sprang up on both sides of the Pennines and with the mills the need for centralised markets declined.

The hall's vast courtyard came to be used for a wide range of events, from political rallies and election hustings to the town's first balloon ascent In 1824. In 1838 it was here that Queen Victoria's Coronation was celebrated and in 1863 around 16,000 people welcomed the Prince of Wales when he came to open Halifax's new town hall. In 1861 the French tightrope walker Charles Blondin crossed the courtyard on a line stretched from corner to corner. And from 1838 to 1890 regular 'sings' by massed choirs of Sunday school pupils drew thousands to the hall.

This has been an enormously complex project, embodying restoration of the historic fabric, upgrading the hall's services and facilities, creating a major space for performances and events, facilitating a range of attractions, from shops and restaurants to heritage interpretation. Just the heading for the planning application, published in 2012, gives a clue to the extent and complexity of the scheme: Alterations to the grade 1-listed Piece Hall and its courtyard; repair of the existing historic fabric; refurbishment of existing windows and external doors; upgrading of existing fabric including new waterproof tanking and new thermal and acoustic insulation; construction of new structural walls; new openings in existing external walls linking Piece Hall to a new extension, the proposed Square Chapel extension and the Orange Box; renewal of existing services; installation of four new lifts; improvement of public toilet facilities; repair and renewal of wall, floor and ceiling finishes; new architectural lighting; new interpretation spaces and installations; installation of new water features in the courtyard; partial demolition of ruined Square Congregational Church; construction of a new four-storey extension adjacent to the Piece Hall and new service road. The planning application was accompanied by more than 270 documents, which included a lengthy historic building survey, conservation management plan, condition report, extremely detailed design plans and special reports on the courtyard and the new extension.

Much time and effort has gone into restoring the hall's fabric, which has suffered from the ravages of time and poor maintenance practices in earlier years. Part of the restorer's skill is in deciding how much to renew and wisely at the Piece Hall the policy has been "to do as much as necessary but as little as possible". To do more would be to undermine the story of the building's history. So visitors will find individual stones, carefully cut and skilfully inserted, for example, into a column in the Arcade while other stones and nearby columns will still exhibit the wear brought about by time but yet continue to function safely.

The new extension, over four floors, is located outside the eastern range of the Piece Hall, between the spire of Square Church and the Square Chapel Arts Centre extension and is not visible from within the Piece Hall. It is designed to house a restaurant, conference centre and service spaces and act as a revenue earner to enhance the Piece Hall's long-term financial viability.

Spaces on the hall's three floors, the Arcade, the Rustic and the Colonnade, are filling up with a variety of shops, restaurants and creative businesses in addition to three heritage spaces. The Piece Hall Story, near the south-east corner is a series of exhibits about the Piece Hall and its history. The Map Room, located below the cupola over the Westgate entrance, has interactive maps about the hall and its place in Halifax and the world. The Trader's Room, in a room on the south side that has been restored to its original condition, shows what it would be like to be at the Piece Hall on a trading day in 1779.

The courtyard has been the scene of an impressive series of events and entertainments since its reopening and as we write the town is looking forward to the Piece Hall as starting point for the final stage of cycling's Tour de Yorkshire on May 6. This in a year that has already seen a royal visit by Prince Charles and Camilla, Duchess of Cornwall and is to be the scene of the BBC's Antiques Roadshow in July.

Indeed the "new" Piece Hall has been making headlines ever since its reopening in August 2017 and has been shortlisted for a sackful of awards. In November Claire Slattery, Calderdale Council's arts and heritage manager, who played a major role in the transformation of the Piece Hall, was winner of the Historic England Angel Award for the category Best Rescue of a Historic Building. The Piece Hall was also the overall winner. The Piece Hall restoration is also among 13 buildings shortlisted by the Royal Institute of British Architects for its Yorkshire Regional Awards. The Piece Hall and the adjacent new Calderdale Central Library are also shortlisted by the Royal Institute of Chartered Surveyors Yorkshire and Humber awards in two categories, building conservation and regeneration. The Piece Hall has also been nominated - by Halifax Civic Trust - for a Civic Voice Design Award and by the Local Authority Building Control's Building Excellence Awards. The Piece Hall has also been highly commended in the British Guild of Travel Writers Tourism Awards. Finally the Piece Hall has been shortlisted for an international lighting award in the International Lighting Design Awards in its Community and Public Realm Project of the Year.

The transformation of the Piece Hall has been a prodigiously complex affair and the scheme did suffer a number of delays which pushed back completion well over a year. But as Calderdale Council's leader, Coun Tim Swift, reasonably explained, for a building of this age there were no detailed historic drawings to help the designers and construction teams. Hundreds of bodies had to be removed from a graveyard on the site, weakened foundations had to be strengthened. Asbestos, discovered on the site, had to be removed. The delays were not an unreasonable price to pay for the magnificent building that greeted the 23,000 who turned up on August 1. For the "new" Piece Hall - described as "an architectural and cultural masterpiece" is a truly magnificent, spectacular building. The materials and workmanship are of the highest order - from the brushed steel and timber gates at the new east entrance to the intricate and so careful repairs to the hall's 239-year-old sandstone columns, from the quality of the courtyard stonework to the granite benches and steel handrails and the spectacular lighting system.

If you can recall the jaw-dropping moment when you first set eyes on the interior of the Piece Hall - perhaps in the 1970s after the hall had served for a hundred years as a wholesale fish, fruit and vegetable market - then you may have relived the experience in 2017. Let's hope that Britain's last surviving complete cloth hall is safe and sound for another 239 years.

The £19.2 million scheme has been funded by Calderdale Council with £7 million from the Heritage Lottery Fund and additional support from Garfield Weston Foundation and the Wolfson Foundation. The Piece Hall is owned by Calderdale Council and managed by the newly formed charity The Piece Hall Trust.

Architects: LDN Architects, Edinburgh. Main contractor: Graham Construction.

The turning point followed a third public inquiry in which the Georgian Group, the Victorian Society, the Ancient Monuments Society, the Save Britain's Heritage Group and Halifax Civic Trust combined to fight demolition. In May 1980 Environment Secretary Michael Heseltine ruled out demolition and also rapped the council for failing to spend a modest £700 to protect the building. Ideas for reusing the building started to flow: a study centre associated with the Piece Hall, a "public auditorium for community activities", offices, shops, restaurant, tourist visitor centre, job training centre, 30 flatlets, 18 flats, 40-bed home for elderly and disabled people, vintage car museum, a restaurant, exhibition and conference centre, a national museum of the non-conformist churches.

In April 1983 the Halifax and national civic trusts proposed turning the building into a £650,000 youth arts centre. The scheme involved building a large glass extension to the rear as well as turning the chapel into an auditorium for 350 people, with a cinema, lecture room and workshops.

And now, almost 50 years since Square Church and Sunday school closed and nearly 30 years since the Square Chapel Trust revealed its vision to turn the building over to the arts, Square Chapel has a second new lease of life - a striking new extension that houses a copper-clad, state-of-the-art auditorium, cafe, bar and box office. At the heart of the extension is the triangular-shaped foyer-cum cafe bar and ticket office.The form was dictated by the restricted space between the ancient street called Blackledge and the Piece Hall. The shape of this space suggested a building in the form of an isosceles triangle with its base attached to the west end of Square Chapel - now called the Red Brick Auditorium - and its apex - the "sharp end" - meeting the south wall of the Piece Hall at a point where the mid-line of the chapel extends westwards to meet the Piece Hall wall. At the east end the triangle meets the chapel just below the cornice and the new roof slopes down towards the exit. It really is a showstopper. From the entrance you have a long view towards the chapel under a rising canopy, a coffered ceiling of triangles in spring and autumn shades of green yellow, brown and cream, held together with white-painted steel beams, the whole supported by white, tree-like columns. There are more trees on the south-facing glass wall, which overlooks a new terrace; here artist Sarah Galloway has created a beautiful artwork, an abstract representation of trees and foliage spread over 29 panes of glass. Indeed the whole structure presents a palette of materials and colour, from the honey-coloured sandstone of the Piece Hall's outer wall to the red brick of the old chapel; from the etched glass of the south wall to the variously coloured panels of wall cladding, from the multi-coloured ceiling to the pale grey concrete of the floor and the wood-grained concrete on the stair well, a little bit of retro modernism set against the warm tones of the chapel's rear wall.

And then, on the limited space between the triangular foyer and Blackledge is the Square Chapel's new Copper Auditorium, seating 110 - compared with the 230 in the Red Brick Auditorium - cosy, intimate, hi-tech, used for small-scale performances and film. It's a bold, copper-clad building, sitting on a deep stone plinth, that echoes the form of the old chapel on a smaller scale and without the pitched roof. The extension also boasts new meeting rooms, a space for Square Chapel's many volunteers, new toilets and, for the first time, a direct link from the foyer to the adjoining Piece Hall. In a reordering of part of the the chapel the old bar has been turned into offices and new dressing rooms provided. The new spaces mean that audiences will surely grow, from 12,000 to 14,000 a year to perhaps 24,000 a year for live performances to 25,000 or more for film shows.

In the early 1970s Square Chapel was described as "the most derelict building in Calderdale". Huge notices warned "Danger: Keep out" and there were those for whom demolition could not come quickly enough. Thanks to that theatre-loving gang of 1988 one of Halifax's most important Georgian buildings was saved and given a new life in the arts. Now, 30 years on, the Square Chapel Arts Centre has come of age. The decades of uncertainty are past. In beautiful buildings of both the 18th and the 21st centuries a much-loved institution in our town is here to stay.

Architects: Evans Vettori. Main contractor: Wildgoose Construction.

Some time after Calderdale Council decided to leave its Northgate House premises and move to mid-Victorian Princess Buildings members of Halifax Civic Trust were invited to tour both buildings. Frankly we found it hard to understand why the council would want to abandon purpose-built offices opened in 1982 in favour of a listed former bank and adjoining shops built well over 100 years before the computer age. How would it be possible to convert Princess Buildings - actually three buildings with dozens of floor levels - into something like modern offices? Here was a warren of tiny rooms, narrow corridors, steep staircases and useless spaces unfit for the modern age. Circulation was hopeless; in places you could go up a flight of stairs just to come down another one. The buildings contained at least 40 different floor levels and there were seven sets of stairs within a 10 metre radius. It read like a construction nightmare. And yet... out of this complexity, modern, efficient, attractive offices have been created at Princess Buildings, thanks to the ingenuity of Leeds architects Bauman Lyons - and without damaging the character of the grade 2-listed buildings or the important high-Victorian townscape in which they lie.

In 1887 the bank was extended south along Princess Street, almost doubling its size. By the end of the century the bank had 29 branches in the West Riding. Ultimately, following a series of mergers the bank became part of Lloyds. The building was sold to Halifax Borough Council for £9,500 in 1939; in the 1960s the council extended the bank further along Princess Street in a building typical of the age, a combination of stone, glass and plastic panels. The Crossley Street and Northgate shops were built somewhat later than the bank. On a 1894 plan they are shown including a jeweller's and others selling hats, linens and crockery. Today all three buildings are known by the Princess Buildings name.

Inside the rejuvenated Princess Buildings the original banking hall has lost the long counter where the public used to pay their bills. Instead there is a large, open-plan space where meetings can take place and the public can talk with officers of the council. Elsewhere, unnecessary walls and staircases have been removed and Princess Buildings now boasts up to four floors of open plan office spaces, some larger than others, but all modern, appealing working spaces for the 450 council workers who moved in last October, representing departments ranging from children's service to public health, environmental protection to legal services, housing to corporate asset management. The working spaces are flexible, using hot desking to maximise the use of the spaces; there are seven desks for every 10 workers. Decoration is simple and refined, with pale grey walls and doors, skirtings and architraves in darker grey. But at the Link sandstone walling from adjoining buildings remains exposed. Signage follows the council's corporate style, with different colours for different function, for example blue for meeting rooms, green for breakout spaces, yellow for kitchens.

Despite the modernisation the designers have made it a priority to retain as many historic features as possible, ranging from ceiling roses, cornices and other plasterwork to original wooden architraves and ornate bannister rails. Two large original skylights have been restored and a panelled room that was once the bank manager's bedroom retained. The bank's original strong room with its safe has been kept as a feature, and so has an Otis lift, installed around the turn of the century but no longer working. One of the finest of the retained historic features is a fine wooden, probably oak, staircase that rises from the ground floor entrance to the 1887 extension with ornate plasterwork and lit by a skylight.

The transformation of Princess Buildings is a triumph, proof that solutions can be found to the most difficult and tortuous architectural problems. Bauman Lyons and Calderdale Council showed the doubters what could be done; they have safeguarded an important part of Halifax town centre's built heritage for several more generations at least and deserve our congratulations.

Architects: Bauman Lyons. Main constructor: ISG Construction.