Link to other question.
Do wood blinds block light.
Light gaps are especially problematic on blackout shades where complete darkness is desired.
Light blocking strips can cover gaps.
Wood blinds are made of different slat sizes which include 2 inch 1 inch 2 inch and 2 inch.
Their cell pockets trap heat and light between them besides lending you the privacy that you desire at all times during the day.
Besides their sleek and minimal appearance they are also excellent blockers of light and heat when they employ more than one sheet of fabric in their construction.
Although there are some blinds with fold flat slats that close tighter to block more light if you want to block a lot of light you re better off with shades.
Also you have to keep in mind that it is block out all light is an impossible thing to do no matter how effective your shutter are.
According to the window designers choosing the smaller slat sizes will lower this risk while creating tighter closure.
Light filtering blinds diffuse the harsh sunlight into soft rays room darkening blinds to block out most of the light and blackout treatments are built to obstruct all the light making any space dark.
Ways to prevent the excess light.
All blinds with slats will let in some light through the spaces between slats.
Keeping the blinds close block most of the light but sometimes blind slats can let a little amount of light to enter your home through the gaps between slats.
Window treatments come in various fabric options which include sheer light filtering room darkening and blackout materials and depending on your requirements you can choose the right one.
Well this is possible but your room has to have no doors or windows.