The next topic on the cards for my series of posts on the impacts of magic on worldbuilding is one which follows closely on from food on the basic essentials list: Shelter.
You've filled your belly, and now in your magical world you're looking for a place to rest, to get out of the sun, the wind, the rain, the cold. To keep the monsters out.
Construction of an adequate shelter will have a large impact on your ability to be not eaten, not sunburned, not frozen. Literally, to not die of exposure.
Where would the classic tale of The Three Little Pigs be with the introduction of magic? The first little pig is a cautionary warning against taking the easy route, and is summarily eaten for choosing a building material which was in plentiful supply and simple to work with. It just wasn't any use at keeping the local smooth-tongued wolf out. Yet a quick spell could have transformed that house of spun straw into close-knitted Kevlar.
Unless transport is cheap and easy, buildings are generally constructed from material which is locally available. Wood, stone, brick, mud and dung. A little glass, if you've reached that point, but it's rare that we see any attempt to build with other materials, even in worlds of magic. Ice occasionally shows up as an option, and the sylvan races like to tailor their trees to include living quarters, but other than the occasional mad wizard building their towers out of solid ruby, it's exceptionally rare to see any non-standard materials used in construction.
If you've awarded your world a truly galumptious amount of magic, what's to prevent you from building your house out of giant rose petals which retain their texture, but have the strength of titanium? A must-have for the truly ostentatious mage (or faerie queen).
A more likely use of magic is in the method of construction. One of the reasons the pyramids are a wonder of the world is the sheer difficulty of transporting stone of that size and weight – even today it would take quite some doing, let alone when your primary transport is wooden rollers and slaves. Levitation would certainly increase your ability to produce towering monuments.
Beyond assisting standard construction methodology, magic can add a lot of variety to your home building options. Straightforward conjuration. Growing your buildings from seeds. Taking the Mickey Mouse route and having your broom do all the hard work. Or enchanting giant arachnids to spin tents with the tensile strength of spider web.
When you mix magic with both construction methods and building materials, you can produce buildings which would make a structural engineer sweat bullets. Gravity-defying spires. Bridges that cross mile-wide expanses without caring for little matters like pylons. Huts on chicken legs which permit a nomadic lifestyle with all the luxuries of home.
It's relatively rare to see extravagantly soaring buildings in fantasy literature, even when there's an excess of magic. The one exception is the floating city, which pops up quite regularly – but oddly enough is usually furnished with relatively ordinary buildings.
It's rare that a world is awarded sufficient magic to make magically-constructed buildings common. But monuments and palaces would certainly benefit from the best which magic could do. If you've given your mages enough pep to send half a mountain whizzing through the air, or produced an irritable little man to demonstrate the method of transforming straw into gold, then consider turning that magical ingenuity to the mundane but ever-so-important question of something to keep the rain off.