Stone Walls

[Rambler]

Hello,

I have a small house, the external walls are stone approx. 2 feet thick, which are plastered internally without insulation. There's no obvious sign of damp. I've always found the house cold and have just had gas central heating installed but find it takes ages to heat the house up and even then it only gets warm to a point.
Is this down to a lack of insulation, if so whats my best approach to improve this.

Thanks...