Kiosk No. 3 (K3)

Due to the high cost of purchase and maintenance of the Kiosk No. 2, the Post Office was asked to look into a cheaper alternative which was visually acceptable (most considered the Kiosk No. 1 to be an ugly structure) to the Municipal Councils.

In 1929 the Kiosk No. 3 (K3) was introduced, again designed by Sir Giles Gilbert Scott (his fee was £52.10.0).  This kiosk was intended for sites of special architectural importance, scenic localities and for general outdoor use in rural and urban areas.  Only a few were installed in London.

The initial tender was for 1800.  600 were from The Croft Granite Co, 600 from the Norwest Construction Co. and 600 from D. G. Sommerville.  The cost of each Kiosk, based on a purchase of 250, was approximately £22.13.4.

In August 1930 it was decided to adopt the Kiosk No. 3 as standard for rural areas once the stock of Kiosk No. 1's had been exhausted.  The unit cost at this point had dropped to £13.00.  In six years the Post Office had installed in the region of 12,000 K3 kiosks nationwide.

The actual design was very similar to the Kiosk No. 2, but was made largely from concrete instead of cast iron.  The Kiosk No. 2 was to be used only in Metropolitan areas due to it's initial cost.  Only the window frames were painted red, with the rest of the kiosk being painted a stony grey colour.

This was the first Kiosk to use Aluminous Cement.  Aluminous cement was used only because it was found that it was impossible for Portland Cement to give a suitable finish or adhesion qualities.  Even though the price of cement was higher, the fact that kiosks could be produced at three times the rate made it cost effective.  Because concrete was a rather poor material for telephone box construction this was the last standard telephone box to employ its use and all subsequent kiosks were made in cast iron.

Coloured inside and outside treated with two coats of cream Snowcem (the colour was described as Clipsham Stone (see picture above) or Light Portland Stone) or one coat of stipple paint to window frame and its exterior surround painted in Red 539.

There were two variants, the Kiosk No.3 Mark 1 (Mark 234) and the Kiosk No.3 Mark 2.  It was found that the roof transom (the section containing the 'telephone' signs) was difficult to manufacturer due to the delicacy of the unit.   To give strength to the corners, the transom unit was discarded and the sides raised.  The 'telephone' sign was reduced in length by 5.25 inches to allow a corner section of adequate strength.  This then became the Mark 2 and was introduced circa 1934.

The 'Telephone' signs are opal glass.

Both kiosks types consist of seven separate concrete sections with the Mark 1 having a Columbian Pine door.

Dimensions - 8ft 7.5ins x x3ft 2ins x 3ft 2ins.

Superseded by the Kiosk No. 6.

Uses Hinges, Brass No. 2  (6" x 3") on the door.

Drawing No's - 8769, 9252, 60470, 60472, 60473, 60474, 60475, 60476, 60477, 60478 and 60479.
Drawing - Concrete Panels (Mark 2) - 60471

Diagram - EC1237.

The above is taken partly from BT archives

For more information and K3 Installation click here

Pictures of the last Kiosk No. 3 in Rhynd, Scotland


Rodney Marshall comments

The earlier references to Stone, indicating a sort of grey colour, are misleading.  The 1971 Non Technical Maintenance Manual R1 states Snowcem Cream and is the colour everyone goes for as it obviously looks nice.

The answer is in a drawing 'Diagram E.C. 1347' of the earliest version the Mk234 where it states Clipsham Stone as the colour.  Clipsham Stone is a light cream limestone building stone quarried in Rutland and Lincolnshire to this day.

It is interesting to note that Sir Gilbert Scott chose a non-standard colour and even the Post Office had problems in describing the colour.  In 1928 the official line was that "the colour lies between Portland Stone and Clipsham quarry stone".




Each kiosk to be made in seven separate reinforced concrete sections, i.e.
sill, floor slab, two side panels, back panel, transom panel and roof; and a wood door, all of which to be strictly in accordance with the drawings. The floor slab, sides and back to be varied in construction in accordance with the requirements quoted in the form of tender, and to meet the conditions shown in Diagram No. E.C. 1337.

The concrete to be composed of aluminous cement and aggregate in the following proportions:-
- 100 lb.
Fine aggregate
- 1
¾ cubic feet
aggregate - 3 cubic feet

The cement to comply with British Standard Specification No. 12 in respect of fineness, tensile strength and soundness.

The fine aggregate to consist of evenly graded, clean, sharp washed sand 1/8 inch down, not more than 5% of which will pass a 100 mesh sieve.

The coarse aggregate to consist of washed granite chippings or other approved stone evenly graded 3/8 inch to 1/8 inch.

The aggregate to be free from ligneous, alkaline, organic, clayey, earthy or soft materials.

Samples of both fine and coarse aggregates to be submitted for approval before commencing manufacture.

The water to be clean, arid free from organic matter, acids or strong alkalis.

The ingredients to be well mixed in a dry state prior to being wet mixed.

The concrete to be thoroughly mixed and worked up to as slightly wet, even constituency throughout.

Concrete which has commenced to set before being put into the moulds not to be used.  All moulds to be carefully filled; the exposed surfaces to be covered immediately with saturated sacking which shall remain in place and be maintained in a wet condition for a period of 24 hours.

Metal, or metal lined moulds, to be used throughout. The moulds to be thoroughly rigid in all respects, to be cleaned and greased with mould oil before the concrete is placed in them to prevent the concrete from adhering.

The materials, mixing appliances, moulds and anything used in connection with the work to be kept entirely free from Portland Cement throughout.

The sections to be clean sharp castings free from cracks, chipped edges, soft spots, camber, twist or other defects and to line up accurately when assembled.

All sections to be adequately reinforced against bending stresses. The reinforcement to be bent, neatly wired and accurately positioned according to Drawing No. 60472.  The single bar for the corner pillars to be wired to the metal sockets which form the screw holes.

The door to be made of first quality dry, straight grained Columbian pine, free from large or loose knots, shakes or other defects.

The door styles and rails to be mortised, tenoned and housed into each other and all joints to be well glued and wedged up tightly. The bottom rail of the door to be made of two pieces of timber grooved and tongued to give a close joint.

The following fittings, all supplied by the Department, to be fitted on the door by the contractor in the positions shown on the drawings.

1 x Handle, Pull.
2 x Straps, Restraining No. 2.
x Spring, door closing No. 3.
2 x
Hinges, Brass No. 2.
2 x Pairs brass end fittings.

The restraining straps to be fitted so that the strain is equally divided between them and to allow the door to open 75degrees.

The door and sashes to be back puttied, glazed with 26oz. sheet glass and beaded..  The glass to be thirds quality, free from seeds and other blemishes. The glass and. beading to be supplied by the contractor.

The door to be fitted right or left-handed, and to be free fitting in its frame.

The back panels to be fitted with Columbian pine battens as shown on the drawing.

All woodwork, including beading to be finished to size, all knots to be thoroughly treated with knotting and the whole to be painted with one coat of stone coloured paint.  In the case of the battens, the priming to be applied on all faces before they are fitted.

After priming, the woodwork of the door to be treated with one coat of stone colour paint.

In addition to the afore-mentioned door fittings, the following fittings and stores to be fitted by the contractor, will be supplied by the Department:-


1 x Steel door frame.
x Steel sign frames.
x Steel window sashes.

x Steel weathering bar.
x Steel plate for spring, door closing
To Drawing
60473 and Specification No. 537.

1 x Conduit Assembly to Drawing No. 60477.

21 x Iron Plugs, 24 Iron Sockets, 8 Conduit Clips and 20 Batten clips to Drawing No. 60476.


18 x No. 8 csk. 1.1/4 in. Window in door.
10 x No. 14 csk. 1.1/2 in. Hinges to door.
2 x No. 14 csk. 1.1/4 in. Spring door closing to door.
4 x No. 6 csk. 1.1/4 in. Handle, pull.
6 x No. 12 csk. 1.1/4 in. Strap, restraining to door.
36 x No. 8 round head 3/4 in Battens and conduit clips.
117 x No. 8 raised head 5/8 in. Sash beads.
3 x No. 14 csk. 1.1/2 in. Door frame to sill.
3 x 1/4 in. dia., B.S.W. csk. 1 in. Door frame to transom panel.

16 x 1/4 in. dia., B.S.W. rd.hd. 2 in. with washers.

Sides to back.
10 x 1/4 in. dia., B.S.W. csk.3/8 in. Hinges to frame.
4 x 1/4 in. dia., B.S.W. csk. 1/2 in. Spring door closing to plate.
3 x 1/4 in. dia., B.S.W. csk.1/2 in. Steel plate to door frame.
8 x 1/4 in. dia., B.S.W. csk. l/2 in. Strap restraining to door frame.
90 x 3/16 in. dia., B.S.W. raised head 1/2 in. Sash beads.
8 x M.S. 1/4 in. dia., B.S.W. csk. 2 in. each with hex. nut and washer. Door frame to sides.

Each kiosk to be marked with the stock list number, the contractor's approved code letter or letters, followed by the last two figures of the year of contract and with a mark number to be designated by the Department.

These markings (with the exception of the suffix letter shown on Diagram No. EC 1337 which is to be painted) to be stamped in 1/4 inch characters on the right hand batten 12 inches from the bottom, and to be in the relative position indicated by the following typical example, in which No. 3 represents the stock list number and 2 the mark Number:- No. 3. FH 35/2.


The kiosks will be inspected at the contractor's works by the Department's inspecting officer, and the contractor to provide the necessary labour, etc. and afford the inspecting officer all the facilities and assistance he may require for the purpose.

The inspecting officer to have free access to the contractor's works for the purpose of inspecting the materials and the process of manufacture in all its stages and have power to reject any materials or sections which appear to him to be of unsuitable description or of unsatisfactory quality.

Each kiosk, on completion of the sections as already set forth, to be erected on the contractor's premises, and screwed up sufficiently to satisfy the inspecting officer that the kiosk will be satisfactory on re-erection.  The window sashes to be glazed before inspection.


After approval by the inspecting officer, the kiosks to be taken down and packed in cases supplied by the Department, and then either stored by the contractor or put on the rail for delivery, as required, at his own expense.

The contractor to supply with each kiosk 14lb of Earle's mastic cement, A quality, grey, packed in an airtight lever-top tin.

Schedule of Drawings, Diagrams and Specifications referred to in this Specification.

April, 1935.



Kiosk No. 3 Mark 1 Exterior Kiosk No. 3 Mark 2 Exterior


Additional Pictures

All Mark 1


Kiosk No. 3 Mark 1 containing a Telephone No. 11 and Coin Collecting Box No. 7.





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