In the UK it's common to have brick/stone houses - the house I was living in before moving to Finland was built in around 1890. Leaky and hard to heat in the w

In the UK it's common to have brick/stone houses - the house I was living in before moving to Finland was built in around 1890. Leaky and hard to heat in the winter, but great in the summer where the solid mass took forever to heat up. You could be indoors on a hot summer day and feel nice and cool, just due to the insulation from the stone/bricks. The only thing I'd do would be shut the blinds during the day, and keep the windows closed until evening-time.