well i was sceptical of these conversions but i ve now personally experienced three in customers homes. all three were unusable as day rooms during autumn/ winter but having all three since xmas i have to say the transformation is marked.
two have had the glass in the roof removed and replaced with a sandwich of plasterboard/ insulation and composite roof tiles. it looks very good inside and out. these are now usable warm rooms in the worst of the weather.
the third was insulation sandwiched between plastic its appearance looks cheap but seems to work as well as the other.
the first solution is something id definately reccomend to a connie owner who gets no use from it oct/march