Frederick Strouts was born, probably in 1834, at Hothfield, Kent, England, the son of Susannah Philpott and her husband, Edward Strouts, a farmer; he was baptised on 5 February 1835. He was educated at Wye College, Canterbury. His architectural training began with John Whichcord and Son in Maidstone and continued under the partnership of Arthur Ashpitel and John Whichcord junior. He later became manager of the District of Plumstead and Eltham under the Metropolitan Building Act 1855.
On 14 May 1859 Strouts arrived at Lyttelton, New Zealand, on the Victory, along with his future brother-in-law James George Hawkes. They set up in business in Hereford Street, Christchurch, as 'General Importers & Ironmongers, Architects, Surveyors & Land Agents'; the partnership continued until June 1872 when the firm was declared bankrupt. The odd-jobbing nature of the enterprise saw Strouts surveying, for example, the site of the proposed Anglican cathedral.
His earliest documented building is Waitui, a residence built in 1861 for Angus Macdonald near Geraldine. Among the firm's designs for commercial premises the ambitious but clumsily modelled stone-fronted Bank of Australasia in Cashel Street (1863) was castigated by the Lyttelton Times as 'an excruciating English version of Italian.' Strouts was more successful with houses for the gentry. He acted as supervising architect for the Acland homestead at Mount Peel station (1865), and was also favoured, in 1867, with the first of several major commissions for Robert Heaton Rhodes; this was possibly Rhodes's Christchurch town house Elmwood, which burnt down and was replaced by Strouts in 1882.
On 30 April 1861, at the Church of St Michael and All Angels in Christchurch, Strouts married Charlotte Rosa Lock Sparshott. In April 1868 the couple returned to England with their young family, and in July the following year Strouts was elected an associate of the Royal Institute of British Architects. They returned, on 20 November 1869, to Christchurch, where Strouts was to pursue an eventful, if erratic, career as an architect.
In June 1871 he was appointed supervising architect for William FitzJohn Crisp's masterpiece in timber, the magnificent new Anglican pro-cathedral Church of St Michael and All Angels, which opened in May 1872. When W. B. Armson fell ill in 1873 Strouts took over the Canterbury Club commission. He was engaged in 1884 to supervise construction of the homestead which had been designed in London by Robert ('Bungalow') Briggs for Sir John Hall's Riccarton farm, Riseholme.
Strouts was notable as an architect in his own right, both prolific – tender notices for over 100 contracts were published over his name – and versatile. In 1877 he won the competition for a model farm homestead at Lincoln with a distinctive Anglo-Dutch design inspired by Rothamsted manor in Hertfordshire, England. Now known as Ivey Hall, Strouts's building survives refurbished as the library of Lincoln University. The former Lyttelton Harbour Board building (1880) is high-Victorian Venetian Gothic in style, while the Rhodes Convalescent Home in Cashmere (1885–87), with its half-hipped gables and mullioned windows, is plainer and more severe in manner. In its design Otahuna (1895), the impressive timber residence on the Rhodes estate near Taitapu, derives from English arts and crafts and American Queen Anne sources. Of brick construction with decorative work in terracotta, the Hyman Marks wing at Christchurch Hospital was also highly eclectic.
In 1901 Strouts carried out what was probably his last notable work: substantial additions to those he had previously undertaken in 1890 at Strowan, G. G. Stead's mansion (now part of St Andrew's College) on Papanui Road. It remains an impressive demonstration of his ability to translate into timber construction those medieval and Gothic forms with which he had been familiar in England.
Strouts carried out further architectural work at the Rhodes Convalescent Home in 1901 and 1903, by which time his career was almost at an end. He appears to have retired from practice in 1905 and his membership of the Royal Institute of British Architects lapsed five years later. He died at Christchurch on 18 December 1919, and was survived by his wife and five of their children. Charlotte Strouts died in 1933.
Strouts played a significant role in raising the professional status of architecture in colonial Christchurch. As a signatory to the architectural fraternity's 'Memorial' published in the Lyttelton Times in 1864, he supported Benjamin Mountfort's bid for appointment as supervising architect to the cathedral. He joined Armson, Mountfort and Alexander Lean in 1871 or 1872 in forming the Canterbury Association of Architects. They published a scale of charges adapted from the Royal Institute of British Architects' formulations, and in 1876 a court case, Strouts v. Saunders, established an architect's right to retain plans for buildings whose construction was not carried out.
Strouts was also active in the community. He served as honorary secretary of the Canterbury Yeomanry Cavalry Volunteers and attained the rank of captain, and was for many years from its inception honorary secretary to the Rhodes Convalescent Home.