Insulate the roof#
Insulate the roof
Roof insulation is the most important type. For a warm room in the loft, use rigid insulation boards between and over the roof rafters. You could lay rolls of insulation on the loft floor. Make sure you meet the modern standard, 27 cm thick, follow advice to ensure adequate ventilation, and consider putting rigid insulation on the loft hatch. If your roof can’t be insulated, you may be able to install a false ceiling and insulate above that.