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Two white apartment facades the smaller one in the foreground, has a wild garden growing on the terrace

Why do apartment buildings need flat roofs?

Have you ever looked at the shape of apartment buildings and noticed that the roofs are almost always flat? Why do almost all of them have flat roofs? You’d think that it would trap a bunch of stuff like debris, rain, leaves, snow, and more up there. But, as you’ll find out, they’re designed in a way that prevents things like rain from building up. There’s also several other good reasons apartment complexes primarily have flat roofs. 

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Did you know "flat" roofs aren't actually flat?

Let’s just get this one out of the way. “Flat” roofs are mostly flat… but have a slight slope to allow the rain to slide off. And, a small slope is still a slope, so it’s enough to help direct the rain off the roof. So, while there’s several different types of flat roofing and names to call each, they all fall under the umbrella of “flat”. It’s short, sweet, and to the point.

Flat roof of the building and views of other buildings and trees

1 - More Cost effective

Companies building commercial complexes like apartments are more likely to be mindful of expenditures, and will want the most effective structure for the most cost effective price. Enter the flat roof. It’s cheaper than a traditional sloped roof in almost every respect. Here’s how:

Flat roofs still have to have UV and water protection material added on, but it’s significantly less than a traditional sloped roof. Which is why some building owners like to utilize the flat roof space as a place to grow tons of greenery, and transform it into what’s called a “living roof”. This not only handles some of the water, it also offers some UV protection. It also just looks nice and really livens up what becomes too often a bleak concrete landscape.

2 - Less Maintenance

One of the most simple ways a flat roof means less maintenance is that it’s just plain easier to access it. A sloped roof requires appropriate planning and safety precautions, which means higher risk of on-the-job injuries, and more labor. Because flat roofs are so much easier and safer to access, repairs might only take a few hours with minimal material and minimal labor. This then ties back into the cost factor.

Bituminous membrane waterproofing system details and installation on flat rooftop.

3 - More Usable space

The final reason, and probably the most obvious – you can put stuff on it! This is perfect for apartment complexes who need the extra real estate to install HVAC units. They might also use it for utility closets or other types of storage units. This is much more useful and cost effective than a traditional attic space, which tends to get used much less.

In conclusion...

It makes much more sense for a commercial complex of buildings like apartments to choose a flat roof. They’re more mindful of cost, more practical and useful, and require less maintenance. You really can’t go wrong!

If you’re needing a flat roof built as part of an apartment complex – we specialize in flat roofs for apartment complexes! Just give us a call or drop by our office.