A nice vacation cottage should be something very enjoyable, not something that is a drain on your bank account. One of the major issues you might have to deal with if you've just purchased a nice vacation cottage is high energy bills. These can end up making you hesitant about heading to the cottage for vacations. And that's the last thing you want. It will result in you keeping the place shut down for most of the year, and only enjoying it a few times during the spring or early fall. However, there are some things you can do that will make the cottage something you can enjoy year round (including the super hot summer months, and cold winter months).
Add New Wall and Attic Insulation
During the summer you are going to be cooling your cottage with an air conditioner, especially when it is super humid and hot. If the walls and attics are not properly insulated, then the cool air can leak out and you'll be spending way to much money on air conditioning. The solution is to make sure that the cottage has proper insulation. The walls might have not been properly insulated if it was an old country cottage that was not used as a year round house. So bring in a contractor and have them open up the walls and add new insulation. Also have the contractors head up to the attic and replace the old insulation with new insulation that is more energy efficient. This would also be a good time to replace that old, open blown fiberglass insulation (which is not healthy to breathe in) with newer foam insulation.
Seal Up Around Any Window Air Conditioning Units
If you are using window air conditioner units, which is common in small cottages, then you need to make sure the windows are sealed up properly. You don't want any of that cold air to leak through the gaps between the AC unit and the windows. So, if the stock frame and siders that came with the air conditioner don't make a good enough seal, then you need to buy some foam insulating panels or some polyethylene closed cell caulking, and seal in the gaps. This can cut down on the amount of cool air that leaks out through the window.
Get New Energy Efficient Windows
One of the big spots to tackle are energy inefficient windows. The old cottage might still have the old windows from many years ago. These windows are likely to be in bad shape, and also not double panned or sealed up properly. So, rather than spend time re-caulking and wasting time on them you should just bring in a contractor who has experience dealing with window replacement jobs. They can tear out the old windows, clean up the entire frame and make sure that the wood is not rotted or in bad shape. Then they can install new weather proof capping (which protects the wood frame that holds the window) and finally install the new energy efficient windows. These will often be double panned to prevent heat transfer. So, during the winter, the heat from your wood burning stove or radiator, won't leak out, and during the summer the cool air from your air conditioner won't leak out through the windows.