With Building Boom Comes Downside Scarce materials and busy subs are making for late completion dates Contractors in some parts of the country are beginning to discover the downside of the recent building boom. Along with rising consumer confidence, reasonable interest rates, and record building activity have come shortages, delays, and increased prices for basic building necessities. In Houston, for example, one of the liveliest construction zones in the country, concrete is in short supply. "Some of our members are on concrete allocations," says Max Hoyt, executive vice president of the 1,300-member Greater Houston Builders Association. Concrete is being shipped first to volume users, including large home builders and industrial contractors building highways and a new baseball stadium.