Planning to Build a Flat Concrete Roof

A flat roof
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When you’re planning to build a flat concrete roof, there are a number of things you need to consider. Although a flat concrete roof can be wonderful for a house, it’s not suitable for every home. It’s more ideal in areas that experience hurricanes because they can withstand extreme winds, unlike wooden roofs.

Planning a flat concrete roof isn’t something to be undertaken lightly. It’s a very major undertaking and one that will require employing a contractor who has experience in the field. You should do your planning in coordination with an architect or engineer as well as your contractor.


One important factor you need to take into account when you’re planning a flat concrete roof is the cost. In general, it’s going to cost you two to four times the amount of a wooden roof. Although it lasts a lot longer, the initial investment is very high so you need to be sure you can afford it.

There are ways to do the job more cheaply but these will not be acceptable to most building codes. The planning needs to be carefully laid out in order to receive a building permit. The cost of this needs to be figured into your budget.


A flat concrete roof is going to weigh a great deal so before you begin to imagine putting one on your home, you have to be sure that your house can support it. If you own a wood-frame home, for example, you’re going to need a lot of structural adjustments in order to support a flat concrete roof and the cost might be prohibitive.

You can use extra interior supports, but what works best is a new construction that’s entirely concrete and has been designed to support this kind of roof. Without the correct support, there’s a high likelihood of the roof collapsing and taking the rest of the structure with it.


There are two ways to make a framework for a flat concrete roof. You can either use removable concrete forms or forms that are made of concrete and insulate the house.

The flat concrete roof itself can be up to 7 inches thick although the greater the thickness, the more the concrete will need be poured in increasing numbers of layers, with each one needing to dry before the next is poured. The roof needs to be thick in order to provide insulation and proper protection.

The roof itself will need a lot of reinforcement in order to be strong across its entire length and breadth and this is supplied by steel bars that create a skeleton. The concrete acts as the muscles and flesh on top of it. Expect the construction of a concrete roof to take a lot longer than a traditional roof since there are many more stages involved.


When planning a flat concrete roof, you should also decide on what finish you want on it. There are a number of possibilities, ranging from bare concrete to tiles or even shingles.