Hi Woodchopper, a week is'nt very long for grass seed to germinate, 2-3 weeks would be more normal at this time of the year but largely affected by the current tempreture and weather, so if you dont get any rain,keep up the watering.
When it does come through, dont be in too much of a hurry to start mowing, allow the fine blades to thicken up and get established and then set the mower on a high setting, just enough to cut the very tips, the grass should soon get much thicker after this Good Luck Tbird+