If the boat is already inside but in a cold space, it is worth making a “tent” from heavy duty plastic sheeting. Especially if you make this in two layers to make some rudimentary double glazing you then have a space that is easy to heat, and easier to keep dust free. You must be able to ventilate to get rid of any water vapour.
This is also useful when do major gluing or resin work.
I used to race against a crew that stored their boat (a First Class 8) in a greenhouse. The boat was always bone dry and light.