Conservatory at Carrow House

Summary

Conservatory built in 1895 by Boulton and Paul of Norwich.

Reasons for Designation

The conservatory, built in 1895 by Boulton and Paul of Norwich, is listed at Grade II* for the following principal reasons:

Architectural interest:

* it is a particularly fine example of the period, designed by one of the most important manufacturers of such buildings and indeed of buildings constructed in parts;
* it was illustrated in Boulton and Paul’s catalogue, demonstrating that this important firm regarded it as a very significant production;
* it is richly detailed using ornate patterns in different materials including ironwork, stained glass and tesserae;
* it is very well preserved, retaining its decorative detailing along with the ventilation and heating equipment.

Group value:

* it has strong group value with other designated assets on the site, particularly with the adjoining Grade II listed Carrow House and garden features, the Grade I listed Carrow Abbey, and the scheduled Carrow Priory which, along with the lodge, gardener’s cottage and former cart shed; the nearby sunken garden; and the pet cemetery, all of which are Grade II listed, contribute significantly to its architectural and historic context.

History

The historical development of the Carrow Works site in Norwich, until 2020 the former home of Colman’s, one of the world’s oldest condiment milling producers, dates back to 1146 when King Stephen granted land in Carhowe (Carrow) to the nuns of the Church of St Mary and St John for the founding of a Benedictine priory (scheduled and listed Grade I). After the Dissolution most of the priory fell into ruin with the exception of the prioress’s house which came to be known as Carrow Abbey. The priory estate passed through various hands, being acquired by Philip Martineau), an eminent Norwich surgeon, in 1811. In 1850, land immediately to the north of the Carrow Abbey estate was purchased by the successful mustard, flour and starch milling business of J and J Colman Ltd from the Norfolk Railway Company.

During the late C19 J and J Colman Ltd systematically acquired adjoining parcels of land on which to expand, including the purchase of the Carrow estate from the Martineau family in 1878. By 1926, the premises had expanded to cover some 50 acres and had a frontage of nearly a mile along the River Wensum. While mustard, flour, starch and laundry blue were still the main products produced at Carrow, Colman’s had started producing "Patent" barley, "Patent" groats and "Waverley" oats in 1925 following the acquisition of rival mustard maker and cereal producer Keen Robinson in 1903. In 1938 Colman’s merged with Reckitt and Sons Ltd, a firm producing household products such as polish and bleach, to form Reckitt and Colman Ltd. In 1995, the mustard and condiment side of Reckitt and Colman Ltd was sold to Unilever, while Robinson’s was acquired by Britvic. In 2017, Britvic announced it would close its Carrow Works factory in 2019, prompting Unilever to review its own future on the site, which led to a decision to cease production in 2020.

On the domestic side, along with developing the factory complex, Jeremiah James Colman also extensively rebuilt a mid-C19 villa on the site between 1860 and 1861, turning it into the family home known as Carrow House. From the elevated site he could also oversee his expanding milling business to the north-east. Correspondence in the Unilever Archive dated 1861 suggests that the prominent Norwich-based architect Edward Boardman and the local ironmonger Barnard, Bishop and Barnards were involved in the building works. In 1895 an extension and conservatory were added to the south end of the house. The conservatory was built by Boulton and Paul Ltd, a Norwich-based manufacturing company that had originated as an ironmonger's shop in 1797. During the C19 it became an iron-founders, a wire netting manufacturer, and also constructed prefabricated wooden buildings, notably producing the huts for Scott's Antarctic expedition. During the Second World War the firm was a major producer of prefabricated buildings, wire netting and wooden sub-assemblies of aircraft. The conservatory at Carrow House is illustrated in their catalogue with the title 'Erected at Carrow, Norwich'.

Details

Conservatory built in 1895 by Boulton and Paul of Norwich.

MATERIALS: hard wood and cast iron.

PLAN: the conservatory adjoins the south-west corner of Carrow House which is situated on a sloping site falling steeply to the north-east.

EXTERIOR: the large timber-framed conservatory has a long rectangular plan of nine bays with canted ends, resting on a brick plinth pierced by ornate iron ventilation grilles. The curved roof has a moulded cornice and a continuous lantern surmounted by decorative iron cresting and at each end by an iron finial and weathervane. The bays are divided by wooden mullions with decorative shaping at the top and bottom. Each bay has three fixed vertical panes divided by wooden glazing bars, and above a keyed semi-circular window with tiny leaded lights bordered by a band of red stained glass. The lantern has the same leaded lights and red border. At the short south end of the conservatory is a double-leaf door with lower wooden panels and a glazed upper panel with a semi-circular window above. On the long east side there is another double-leaf door at the right end, and the middle three bays project forward under an elaborate ogee gable head. This is surmounted by a triangular pediment and filled with three panels of Art Nouveau stained glass.

INTERIOR: the conservatory has an aisled wooden structure, each bay divided by a truss supported by aisle posts, with spandrels containing ornate ironwork in the form of cinquefoils and scrolls, and drop finials. Around the inside edge is a slightly raised platform, laid fairly roughly in red brick, which may originally have been beds that were later filled in. The main area of the floor is a large oval mosaic laid in white, bronze and black tesserae, surrounded by a scalloped iron grille with a border of bronze and black. At the south end of the conservatory is a similarly bordered circle, now filled in, which may originally have been either a bed or perhaps a pond. The heating and ventilation apparatus are in situ, consisting of hot water pipes and lever mechanisms attached to the aisle posts for opening the windows along the ventilation ridge.

Sources

Other
Bayne, AD, A Comprehensive History of Norwich (1869), pp84, 605-9
Colman H, Jeremiah James Colman: A Memoir (1905)
Cotswold Archaeology: East Norwich Development, Norwich, Norfolk: Built Heritage Appraisal (2021)
Iceni Projects, Carrow Works, Norwich: Baseline Heritage Assessment on behalf of Fuel Properties (Norwich) Ltd (2021)

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