BUILDING MATERIALS.

Auckland Star, Volume LX, Issue 258, 31 October 1929, Page 8

BUILDING MATERIALS.

MUCH YET UNLEARNED

RESISTANCE TO WEATHER

"How little do we know about building, after all," said a well-known architect, gazing- at the green side of the Wellington Town Hall, and then going on to remark that it was time Wellington had a new one. Referring to the manner in which successive generations grope for tlie imperishable in building, the architect, looking up at a green lichened wall, remarked that builders and others concerned were finding out a good deal about cement, and just how resistant it was to the effects of weather over a long term of years. "Do you sec that green all over the building? ,, he said. "That is vegetation. Up higher, and on the ledges out of the sun, you will find it much thicker. If; holds the moisture f6r a long time. Cement-faced buildings can only hold out so long before that moisture gets through. You may have noticed that many cement-faced" buildings of twenty or thirty years of age are being painted. People have imagined that their owners have too much money and are saving a bit of income tax.. Nonsense! They are doing it because they have been advised, and very wisely advised, to do so. Paint preserves cement and brickwork, as it does wood, by closing up* the pores, and so preventing that capillary action which eventually means dampness inside as well as outside the building. "How little do we building after all," he continued. "Only ten or twelve years ago there was quite a passion -for breese concrete structure mostly floors. Now our technical papers tell us that the sulphur content left in the coke used in the 'breese , is having a deleterious effect on the steel reinforcement; so what with the inroads of damp and the chemical effects of the materials we are still guessing to some extent. I .no one safeguard against damp penetration seems to be the hollow wall, which at all events, prevents dampness reaching the inside wall." °