Position of radiators in a 1810 but house with poor circulation of air prone to condensation

Hi Evelyn, Radiators can go on either internal or external walls – years back they were mostly put under windows to help push warm air around the room, but nowadays position isn’t as important as making sure the heat output is right for the room size. If the rad is too small, you’ll always struggle with cold spots and condensation. The trickle vents in the sash windows will help with fresh air coming in, but they’re not really enough on their own if the circulation in the house is poor. You’ll want the right size radiators, and possibly to look at improving airflow with extraction (like in kitchens/bathrooms) to get on top of the condensation.