February_1968 — Page 17

in future at both the design and assembly stages. There was also a number of joints in floor slabs that leaked when flats were washed down; but they were easily repaired, and here, again, it is thought that the wet joint may have been disturbed during the setting process.

In all other respects the building is giving perfectly satisfactory service.

Contract

The purpose of the scheme was not necessarily to reduce the building cost, although this would be the long term objective, but to treat it as an experiment to produce a block of flats using a non-traditional method at the same cost as a similar block built in the traditional method.

The nature of the offer from the contractor was somewhat unorthodox, and it necessitated adopting new contractual procedures. A set of special conditions was drawn up by Langdon & Every to supplement the Housing Authority's standard form of contract, the Authority bearing the cost of this work.

In December 1966, Goodman Corp. (E. & B.) Ltd. in association with Taisei Construction Co. of Japan, formed new new firm by the name of Hong Kong Tilt-up Corp. Ltd. and the contract was awarded to the newly formed company with Goodman Corp. (E. & B.) Ltd. indemnifying the Housing Authority for any claim or loss and guarantee- ing due performance of the contract.

The special conditions included, inter alia, the following items which were not covered by the Authority's standard Conditions of Contract:

1. "Actual Cost" comprised the

2.

3.

net expenditure directly in- curred by the contractor in respect of labour and materials ordered in connection with the works, the net cost of the use of all the mechanical and non-mechanical plant on the works based on the schedule of plant hire rate agreed with the contractor, and lump sum fixed fee.

a

"Guarantee Maximum Cost" was derived from a bill of provisional quantities based on a similar block previously constructed, and was broken down into five heads Preliminaries, Foundations, Superstructure, Drainlayer, and External works. "Adjusted Maximum Cost" meant the sum derived by adding to or subtracting from the Guaranteed Maximum Cost the value of all variations ordered under the contract and by adding the amount, if any, of the "Fluctuations in Wage Rates" agreement. The contract also provided a payment to the contractor by way of advance a mobilization fee equal to one-half of the value of the heavy plant required up to a maximum of

Far East Architect & Builder February, 1968

January 1967. Finished building almost ready for occupation

HK$300,000 when the plant was delivered and in working order on site. This fee was deducted in equal instalments from the monthly certi- ficates as the work progressed, to the intent that at the completion of the works or prior to removal of the plant the mobilization fee would have been repaid to the Authority.

A clause was also included on "Fluctuations in Wage Rates" to com- pensate the contractor if the labour cost should increase by more than 20 per cent. from those in June 1964 when the work was originally intend- ed to be carried out.

In order to assess the actual cost accurately, it was also agreed that the contractor's working accounts on the project should be made available for checking by the quantity surveyors all through the contract.

Conclusion

素

high dado panel; it is the best way to treat the problem with traditional construction. But with precast work it would have been better to fill the whole opening with a concrete panel, with a hole in for the window. The balcony fronts reproduce the vertical slots of the traditional form, and this complicated the casting.

In other words, if we had to start all over again, and with the knowledge we now have, we could effectively, as architects, make a worthwhile con- tribution towards the economy of the project in the earliest design stages.

One object of the exercise, of course, was to find out if system building could be carried out effec- tively under local conditions; what modifications would be required, if any, to the techniques developed else- where; and how a building so con- structed would withstand local weather conditions. Above all; could it save money?

With the expiry of the six months maintenance period in August 1967, the experimental aspect of the exer- cise came to an end.

a The Housing Authority now has an extra block of 224 dwelling units to extend its Fuk Loi Estate. To all intents and purposes this block is no different from the other four 'L'-shaped seven-storey blocks on the estate and this is perhaps the first lesson.

The structural designers went to a great deal of trouble to reproduce exactly the traditionally built blocks and this was quite unnecessary. We wanted 224 flats to house 1,344 peo- ple, half the flats in 7-person size and half of 5-person capacity. In the traditional buildings these are arranged one of each size on either side of a central corridor, but the prefabricated scheme could have placed all 7-person flats in one "leg" and all 5-person in the other and thus achieved greater standardisation.

Each flat has a window filling the space, full room width, above a 3 ft.

As to the first, there is no doubt that the Hong Kong building indus- try, normally very conservative industry in any country and generally highly resistant to change, can take to systemisation very well. The labour employed by Goodman and Taisei was recruited as for any normal building job; it was not specially selected. The workers learned quickly and produced good results and, apart from the piecework aspect mentioned earlier, no union or cartel problems arose.

One fatal accident occurred whilst the panels were being fixed, and with such large elements being hoisted around a fairly congested area, it is perhaps pertinent to suggest that a greater than usual awareness of site safety is required on such schemes.

No modifications of any conse- quence to the established Japanese methods were called for, but two points may be worthy of mention. There are two basic production

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