How to use your shades
Your shades stop the sun's heat before it reaches the glass. The best position depends on how warm it is outside and where the sun is — here are the three positions to move between through a hot day.
Closed and fully shaded
The window is shut and the shade covers the whole window from the outside. It's held by the dowels on the inside of the window, top and bottom — so nothing is drilled or fixed. The fabric takes the sun's heat before it can reach the glass and warm the room.
When to use: most of the day during a sunny heatwave. Position it before the sun reaches the window — especially if you're heading out. It's the most secure position too, so it's the one to leave when the house is empty.
Bottom vented
Open the bottom sash a little and pull the shade through the top a little so the gap at the bottom is left clear. The shade stays held by the closed window at the top, the glass stays shaded, and cooler air from outside can flow in underneath.
When to use: when it's cooler outside than in but the sun is still on the window. Typical cases: east-facing windows catching the early sun before you're up, or west-facing windows in the evening when the room is warmer than the air outside but the sun is still strong.
N.B.If the window can be reached from outside, consider a window restrictor for peace of mind.
Vented top and bottom
A variation on the bottom vent: crack both the top and bottom sashes so air can move through freely. The shade hangs over the top of the top window sash and covers the middle of the window.
When to use: when you want as much airflow as possible. You'll block a little less sun than the other positions, but still cut the sun's radiation by more than half.
N.B.On a windy day you may need to secure the shade so it doesn't lift.