UNIQUE ACHIEVEMENT

Rotorua Morning Post, Volume 1, Issue 11, 4 September 1931, Page 3

UNIQUE ACHIEVEMENT

CONSTRUCTION OF WARD BATHS WINS TRIUMPH OVER NATURAL DIFFICULTIES L GAS AND CHEMICALS CREATED ■ COUNTLESS CQMPLICATIONS Although it has not yet heen officially opened with all the pomp; •and panoply of hunting and speech-rnaking (perhaps a happy release), the new Ward Bath building in the Rotorua Government Gardens, is now an established institution. But it is more than that. It is, in fact, a quite unique achievement, not only as one of the most modern and best equipped hath buildings in the Southern Hemisphere, but in the triumph; which it represents over what are perhaps the most difficult building eonditions in the world.

Men have ereeted buildings in many strange places but never in one stranger than this. Built on the pumice bottom of the lake bed above boiling springs and mud pools impregnated with powerful gases and chemical elements, the ordinary ideas and appliances of building construction had to be jettisoned to meet eonditions which made their application an impossibility. Under the action of the acids and gases "rising from the foundations nails and screws rotted in the space of days, metal fittings shining and burnished one day, became blaclc and unsightly the next, paint which would meet all ordinary requirements, became hard and discoloured, and stout timber which would stand any test under normal eonditions, rotted like flax fibre. But as though these were not sufficient perplexities for the man who directed the construction, the gas emanations rising from the soil made work on the job, under certain weather eonditions, hazardous in the extreme and fraught always with the danger of the unexpected. Triumph of Construction In the completion of the work, with a minimum of waste and in a record time, was a triumph of building construction in which man's technical knowledge and ingenuity was pitted against some of the most insidious and difficult forces of nature. Before even a start could be made upon the erection of the new baths, the old baths building on the same site had to be dismantled — in itself a work of considerable difficulty. | Timbers and foundations were found to be rotted under the powerful influence of acid gases while the peculiar construction of the ground in which the foundations were laid, further complicated the work. Despite this, however, the old building was completely dismantled in under three months and in Mareh of last year, a beginning was made upon the erection of the new strueture. Instructions had been issued that the building was to be ready for the tourist season, yet in spite of the unique difficulties with which they had to contend, the men in charge of the job carried out their instructions and had the building ready for use by the public early in December of last year. The only portion of the construction uncompleted by that time was the fittings in the Priest Baths, which had to be specially ordered from abroad and had not arrived when the remainder of the work was completed. Tough Heart Rimu The difficulties of the work were largely increased by the fact that only the toughest of heart Rimu timber could be used — wood into which it is impossible to drive a nail with a hammer, but which has to be bored and pinned. Careful investigation had sbown that this incredibly tough wood was the only timber which wiuld withstand the acid action; totara generally considered a sound building material, rotted^ into shreds like flax fibre under the insidious ravages of the gases. The drainage system also, usually moderately straightforward construction, had to be specially built to meet the thermal eonditions. Every foot of drain had to be made accessible for cleaning in order to remove the silica deposit — sufficient, unless regularly extracted, to fill a 4in pipe in 12 months. Corrosion Difficulty. Where nails and screws were used, they had to be specially galvanised to prevent corrosion, while scores of tests had to be. made before metal fittings were found which would withstand the eonditions. In one case, a patent brand of steel fitting, guaranteed acid proof, and stamped to that effect was tested. At the end of 10 days, the whole of the fitting had been eaten away with the exception of the Stamp which guaranteed the product against corrosion. „Whether the stamp itself lasted very much longer is not reeorded. All floors in the building had to he specially construeted. Nails could not be used and the timber had to be pinned with wooden pegs, and caulked after the style of a ship's deck at the joints. Specially Treated All timber used* on the job had to be specially treated with bitumen paint in order to prevent the acid from destroying the eellulose tissue and causing the wood to rot. In addition, ventilation channels between the walls had to be construeted in order to carry away as far as possible, the gas fumes which collect and rise from the acid impregnated soil, all work which considerably complicated the construction. The roof, over the rear portion of the baths where the acid action is strongest, was subjected to severe acid tests and it was found that the only material suitable for the work was a patent product consisting of iron, coated on both sides with abestos, and with the edges treated with bitumen. Hundreds of Tests The paint and varnish problem was one of endless perplexities and hundreds of searching tests had to be carried out to determine the suitability of the brands submitted. With very few exceptions, they were found to be quite unable to withstand the acid

action and had to be rejected. An interesting record of the labour entailed in this section of the work is ra. large scale plan which has been drawn up by Mr F. Barnicoat, the Public Works Department foreman, who supervised a large proportion of the construction. This plan has annotations showing the different paints tested with the resultsffihey yielded, and furnishes an illuminating sidelight upon the vokrme of 'work which had to be carried out before any material could be accepted. The majority of the paintihg had to be done with a spray gun, and ih some portions of the building successive coats of special paint had to be applied before it would retain its colour. This was partieularly thecase in the Priest Bath room, where» the acids in the air made it necessary ' to apply no less than eight coats of white paint before a proper finish could be obtained. It was found by experience that the ' painting of these bath blocks s could only be carried out on exceptionally fine days when the atmoSpheric pres-' sure was high and the wind was from • the north. Work under other eonditions than these, on very many days," was impossible owing to the prevalence of bad gases in the air and the amount of steam and condensation rising from the thermal springs. Marble Eaten Away ' . An exhibit which has been carefully' preserved by the works foreman is a block of solid chipped marble which after three days exposure to the acid I eonditions is practically eaten away. Ordinary lead, it is stated, would not last six months under these eonditions and copper less than a month. High auality bronze fittings were ordered, but when tested, were found to turn almost immediately green and black, like an old copper thrown out on the dust heap. The only safeguard against acid action on the fittings was found to be intensive chromium plating. Special Construction The only effeetive timber for use in the wall panelling was found to be a fine waterproof wall board which, gave a highly ornamental finish and has adequately withstood the eonditions. The first specifications stipulated that the walls should he lined with rubber sheeting but it was found that this would involve a very large outlay and that the pine waterproof timber could be used as effeetively at a tenth of the eost. The outer walls have been construeted of a special pulped timber composition, treated with sand, which". gives a concrete effect but withoUt crumbling under acid action. .J , Gas Fumes * h The most difficult portion of the work was thfe erection of the Radium. and Priest baths which, with their high chemical content, made eonditions extremely hard to combat. Sulphuric acid, carbonic acid, hydrogen. sulphide, and sodium and aliminiumsulphates are among the chemicals in' the Radium bath waters, while in the Priest baths are potassium chloride,. sodium chloride, sodium sulphatq,.. aliminium sulphate, ferrous sulphate/, calcium sulphate, and magnesium sul-; phate. Working in the pumice' bed from which the springs which supply thie ; baths have their outlets, the workmefi; were continually overcome by the acid gases which had the same effect upoil " them as tear gas. At first gas masks " were used, but it was found that the'ser were quite useless as the condensatiofi ' clouded the lenses and made it im-j " possible for the men to see. - > Air Pumps Used • -i The difficulty was finally partially solved by using powerful air pump's^ * which kept fresh air circulating and' - f orced out the gases. All precautiong " were taken to safeguard the men eni- * ployed in this work, but despite this, under, the influence of the fumes, s'ev?.. eral men collapsed. Another difficulty to be contended"' with was the continual influx of water from the springs and so great was its flow that three 30,000 gallon cap--acity pumps could not reduce the head of water. Finally, the cementing of the tiles for the Radium baths had to be carried out under water using a special preparation of molten sulphur as cement. Boiling Poql Discovered A fresh complication was encountered when the old Duchess bath was demolishecf and a boiling sulphur mud pool suddenly made its appearance in one corner. In order to cope with this development, special gas tiled drains had to be laid to carry away the fumes into the lake. The building itself is a handsome structure of classic design and one which reflects credit on both the architects and the Public Works Department, which was responsible for its erection. Spacious in everything, with lounges and rest rooms restfully and comfortably furnished, it shows' evidence of a discerning taste in its arrangement. The wall finishes have been well carried out and. an op.en fountain eourtyard with a promenade giving a splendid lake view is one, of its most pleasant features. As' it stands at present, it is one of New Zealand's finest public buildings, but when the inner history of its erection is written, it must also stand as a monument of determination and technical skill in buii'ding construcrAv tion. , ;;i . : -rr^.l(Lil v ^ i