US homebuilders' confidence in the housing market has risen modestly but remains at low levels for the third straight month, constrained by tight credit for home buyers and a shortage of workers and available land.

The National Association of Home Builders/Wells Fargo builder sentiment index, which measures confidence in the single-family home market, edged up to 47 in April from 46 in March, the homebuilders group reported on Tuesday. Readings below 50 mean builders view sales conditions as poor. The index had been above 50…