Contracts for construction of all types rose 14 per cent nationally in February to $7.5 billion, a 14 per cent increase over the same month the previous year, the F. W. Dodge Division of McGraw-Hill Information Systems reported.

While residential construction showed the largest gain -- it totaled $3.4 billin, up 34 per cent -- federal public works spending was a key factor in shoring up sagging industrial building down 12 per cent, according to the construction information firm.

Construction contracts in the Washington area totaled $58.5 in February, 24 per cent higher than a year earlier, Dodge reported.

The construction market reporting firm said residential construction contracts were up 42 per cent, from $37.3 million to $53 million, while non-residential building was down 8 per cent, from $21.2 million to $19.5 million.

For the first two months, residential construction contracts arrived at here were 57 per cent higher in dollar value, the firm said.

Nationally, the first $2 billion in grants to communities under the Local Public Works Act of 1976 helped bring nonbuilding construction up by 4 per cent over February 1976, though the first two months of this year still lagged 12 per cent behind last year. Highway projects were nearly double their 1976 February value, and sewer and water contracting rose by 30 per cent. Electric power projects, on the other hand, were cut back sharply.

"It is expected that as the economy's recovery strengthens over the balance of 1977 and into 1978, rising industrial and commercial building will gradually displace the present need for this form of stimulation. In the meantime, however, these special public works funds are effectively filling a void," the Dodge firm's chief economist said.