Simply measure from the inside of the brick at the bottom to the inside of the brick at the top and write down that measurement.
Simply measure from the inside of the brick at the right hand side to the inside of the brick at the left hand side and write down that measurement.
Having problems from the sun shining through our front windows and heating the house we called Pelican Roller Shutters. Andy recommended we install shutters because of the thermal insulation properties they supplied. We were pleasantly surprised at the amount of heat they actually cut out.
We were having problems getting our children to sleep due to noisy neighbours. After Andy from Pelican Roller Shutters installed shutters on the windows we have now have no problems whatsoever.