Semi-d garage insulation

Hi all,

I'm new here so sorry if this question has already been asked.

With regard to a 45 year old semi-d with garage. The garage has a flat roof and was converted into a kitchen which is beyond freezing in the winter.

What would be the best way to spend around €800, including the €500 grant, to make the kitchen warm?

It has a storage heater and a radiator from the oil central heating, but it's like an ice-box, despite this.

Thanks.

Which €500 grant are you referring to? There are a number of [broken link removed] grants available, but improvements have to be applied to the whole house, and not limited to single walls/rooms or sections of ceiling.

Without knowing more detail about the current construction, it's very hard to say. There's likely no insulation under the floor, in the walls or ceiling.