leaf problems on houseplant

The leaves on my houseplant are becoming dry and brittle.  Is it overwatering, underwatering or something else? Can anyone help?

If they are in a window-then it is scorch from the sun's rays-either that a too dry atmosphere

Where are they positioned and which plants?

Most of our houseplants come from the jungle where they are in shade most of the time.  Even our summer sun through glass is too strong for them.  Move them away from the window and mist them.  Also you can put them in the bath or shower and wash them - gently.  They will love it!

Another way of making the atmosphere more moist is to get a large plant pot base, as large as you can fit, and fill it with pebbles that are kept constantly damp. Then sit your plant, in its base, on top- the evaporating moisture will give it an atmosphere that it will enjoy.

Thanks guys that sounds about right, will move it away from the window and give it a shower!

Which plant is it, by the way? Some, such as African violets and streptocarpus, don't like being misted.