Different roof shapes can change the look of your home, as well as give you different layout options for a room that is built into the roof. There are typically three main roof shapes that are used for different effects on house: gable, hip, and shed. Sometimes flat roofs are used to give a modern or urban look, though flat roofs may not always be allowed in residential neighborhoods, especially those with HOA restrictions or within zoning areas that have architectural guidelines required by the planning department. There are also some more speciality roof types like gambrel, mansard, or barrel that correspond to specific design styles, but for this post, I’m concentrating on the main types that area most commonly used.
To illustrate the different roof shapes, I’ll use my house as an example. I have a gable for the roof over the main body of my house and over my garage, though they are clipped or hipped at the end. My front porch has a hip roof.
Gable Roofs
This is what my house would look like with all gables. I actually wouldn’t mind if the main and garage roofs were plain gables instead of clipped. It looks nice and clean. However, I think the front porch looks a little odd as a gable because it has to have such a shallow slope to clear the windows. I think the hip roof for the porch was probably chosen for this reason.
Hip Roofs
Here a version of my house with all hip roofs. There’s not too much difference on the main body of the house. However the roof over the garage has to be raised to still have a bonus roof above (unless a dormer is added, which I looked at below). Without the bonus room built into the roof, it appears as a bigger house because of the added wall space when the roof is raised.
Shed Roofs
I tried putting shed roofs all over my house, and it turned out very different! Shed roofs are typically used for small additions attached to the main house (like sheds, thus the name). It works for the front porch, but in order for the second story and bonus room to still be there, I ended up with a third story! Because shed roofs don’t come back down after reaching a peak in the middle, they cause quite a height difference between the two walls supporting them.
Flat Roofs
My house with all flat roofs was the most dramatic change of them all in my opinion. I don’t know if I like it on a traditional two story house. But it would be nice on a house that wasn’t very wide (like a row home). It would be cool to have a roof deck, though.
Dormers
Earlier I mentioned dormers as a way to not raise the roof but still have enough space that can be built into the roof for a room. I made all hip roofs but kept the garage roof at the same height. At the end I added dormers with different roof shapes (gable, hip, shed).
Remnant Architecture 
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