Gun House and Magazine Stores, Orlock Coastal Battery, In the grounds of 25 Coastguard Lane, Orlock, Groomsport, Co Down BT19 6LR

The Department's description

Exterior description and setting

A single storey, flat-roofed concrete structure, rendered and painted, facing northwards, located in the garden of No. 25 Coastguard Lane, Orlock. Largely windowless, a modern partly glazed bay has been added to the seaward elevation, within what was once fully open north eastern bay. This Former gun house which was originally two buildings, has been enclosed and re-roofed to create guest accommodation for the adjacent residence.

The building's original
setting would have allowed uninterrupted views over Belfast Lough towards Kilroot and the Copeland Islands. This setting is as original to the north and north west, but lands to the rear/south have since been developed into large detached houses whose gardens now overlook the lough. To the north is a National Trust managed coastal path and foreshore over which this site now looks. Visible from the site is DHR 00330:003, a Coast Artillery Searchlight position.

Concrete footing/pad partly visible below the building to the perimeter where excavated to the N/NE.

The building has had excavation carried out recently to its immediate perimeter which reveal the depth of the concrete walls to be roughly 300-900mm below existing ground level. The mains sewer line runs somewhere to the N/NE of the building; manhole is evident approx 5 - 6m from the original face of the gun house.

The building is approached from the south, where the eastern elevation which faces the more recent house becomes the main elevation. This elevation would have originally shown two buildings which have now been covered as one by a timber framed and felted roof. Walls have been rendered and painted. There are three vents visible to the right of a door which spans what was the gap between the stores and the main building.

To the north elevation a later 20th C flat roofed addition has been added to enclose what was the opening for the gun. This addition is of no interest, being of recent construction with uPVC sliding double door to left, large uPVC picture window to right and decorative circular light to east.

Western elevation is plain, painted render.

Southern elevation is partly obscured by planting and is largely plain.

Walls: In-situ concrete, rendered and painted
Roof: Flat roof felted, set on original flat concrete panelled roof
Windows: Modern uPVC
RWPs: Modern uPVC

Historical information

This structure was built in 1940 as part of the wartime coastal defences for Belfast Lough.

Background - At the start of WWII, the WWI vintage coastal batteries at Kilroot and Grey Point forts were fully manned, and an ‘examination service’ (marine and coastal defences intended to examine and verify shipping coming in to port) was established at Belfast Lough. There had been some changes during the inter-war years, as defensive strongpoints were added to Grey Point, whose wall was made pentagonal. Grey Point also received two searchlight positions (known as Defence Electric Lights) and a new battery observations post. Changes continued to be made during the course of the war. Searchlights (re-designated Coast Defence Searchlights) were added to Kilroot, and concrete shelters for the Mk VII guns were added due to the increased vulnerability of coastal batteries to air attack. Four guns were insufficient to protect a major port like Belfast, however, and two new batteries were built during 1940; one at Larne, County Antrim and the other, here, at Orlock, County Down.

The Orlock battery was established in August 1940 with an initial emplacement of one 6-inch Mk VII gun, with an additional, second gun noted as having been 'mounted and in action' by the following November. Known as ‘C coast battery’, the installation (which was manned by the Auxiliary Territorial Service), took over ship examination duties from the battery at Grey Point in February 1941. The site had two gun houses along with two searchlight positions. The westerly gun house was subsequently converted to a dwelling house (present no.29 Coastguard Lane) and has been considerably enlarged over the years. That to the east (now in the grounds of no.25) was somewhat unusual in that it was originally two smaller, closely positioned but separate structures which were linked c.1950s. Overall, it has witnessed much less alteration, the most notable recent change being the addition of a projecting bay to the north side, with the building latterly used as a games room, now guest accomodation.

The Mk VII gun would have been mounted just forward of the open face of the concrete shelter (the shelter was to protect the crew not the gun) to maximise the arc of fire of the gun. This area has been built over with the construction of the north-facing bay, so it is not possible at this time to assess if there are any remains of the original mounting/holdfasts.

The battery at Orlock was one of five in Northern Ireland during WWII. Two pre-existing sites at Grey point and Kilroot, and three emergency batteries constructed after the outbreak of war in 1939: Orlock, Larne and Magilligan. All save the battery at Magilligan were fitted with protective concrete gun shelters. The shelters at Larne and Kilroot were demolished post-war, leaving only those at Grey Point and Orlock extant. The western gun house at Orlock has been incorporated into a private dwelling, leaving this site as one of only three largely intact coast artillery gun houses in Northern Ireland.

References - Primary sources
1 PRONI CAB3D/10 War diary, Fixed defences (Belfast Lough) - Aug 1939-Dec 1944
2 National Archives TNA WO 192/324. Battery commanders standing orders - 19 June 1944
3 PRONI CAB80/50 Report by the Defence of Bases Committee re. the 'dismantling of coast artillery guns' - 21 September 1945 [This document mentions the presence of the '2 x 6-inch naval guns' at Orlock.]
4 OS map 1962-64

Secondary sources
5 Clements, Bill, ‘Defending the north: the fortifications of Ulster 1796-1956 (Newtownards, 2003), pp.86-87, 90, 116-17
6 Carr, Peter, 'Portavo - An Irish townland and its peoples Part Two', (White Row Press, Dundonald, 2005), pp.594, 685 [Carr remarks that 'The battery is chiefly and not very kindly remembered for letting off practice rounds at 2am in the morning, thus waking up the whole neighbourhood. These guns "had some thump off them". When they went off, windows shook two miles away in Ballyfotherley. (Harry Humphreys, pers comm. 2004.]
7 O’Neill, James, ‘A review of the Defence Heritage Record for DfC: Historic Monuments Division’ (April 2018), pp.61-63

Criteria for listing: architectural interest

B. Proportion
D. Plan Form
E. Spatial Organisation
F. Structural System
H-. Alterations detracting from building
I. Quality and survival of Interior
J. Setting
K. Group value

Criteria for listing: historic interest

Y. Social, Cultural or Economic Importance
Z. Rarity
W. Northern Ireland/International Interest

Evaluation

This structure was built in 1940 as part of the wartime coastal defences for Belfast Lough. Roughly square in plan, the single storey buildings are now conjoined by a single felt roof. The building faces roughly north towards the lough, and is located in the front garden of No. 25 Coastguard Lane, Orlock; it has in recent times been converted into guest accommodation.

The Orlock battery was established in August 1940 with an initial emplacement of one 6-inch Mk VII gun, with a second added by January 1941. Known as ‘C coast battery’, the installation took over ship examination duties from the battery at Grey Point in February 1941. The site had two gun houses along with two searchlight positions. The westerly gun house was subsequently converted to a dwelling house (present no.29 Coastguard Lane) and has been considerably enlarged over the years. The building to the east (now in the grounds of no.25) is somewhat unusual in that it was originally two smaller, closely positioned but separate structures which were linked c.1950s. Overall, it has witnessed much less alteration, the most notable recent change being the addition of a projecting bay to the north side, with the building latterly used as guest accommodation.

The Mk VII gun would have been mounted just forward of the open face of the concrete shelter (the shelter was to protect the crew not the gun) to maximise the arc of fire of the gun. This area has been built over with the construction of the north-facing bay, so it is not possible at this time to assess if there are any remains of the original mounting/holdfasts.

The battery at Orlock was one of five in Northern Ireland during WWII. Two pre-existing sites at Grey point and Kilroot, and three emergency batteries constructed after the outbreak of war in 1939: Orlock, Larne and Magilligan. All save the battery at Magilligan were fitted with protective concrete gun shelters. The shelters at Larne and Kilroot were demolished post-war, leaving only those at Grey Point and Orlock extant. The western gun house at Orlock has been incorporated into a private dwelling, leaving this site as one of only three largely intact coast artillery gun houses in Northern Ireland.

Despite reversible additions to the interior, the gun house and stores' largely original materials, form, structure and plan form can be seen and its significance as a simple military defence structure understood. Open views of the coast and lough remain, unchanged, and are evidence of its important defensive position and largely intact setting. The building has group value with the Searchlight building (DHR00330:001) just beyond; together these two rare upstanding buildings form a group of special architectural and historic interest, whose relationship to the lough give this location significance in terms of a collective understanding of defence heritage structures still in situ in Northern Ireland.

General comments

This building is on the Defence Heritage Record - DHR00330:002.