The steel joists will provide a strong foundation for the flat concrete roofing.
Concrete slab flat roof detail.
Concrete slab flat roofs.
When building a flat roof it is vital that a degree of falls is built into the construction to ensure rainwater run off.
Step 3 placing the steel joists.
The definition of a flat roof according to bs 6229 is having a pitch less than 10 o to the horizontal however some in the industry would consider up to 15 o as their definition of a flat roof.
The simplest way to construct a roof terrace is by utilising a concrete slab.
D 2 21 waterproofing between layers of thermal insulation d 2 22 flat roof with impermeable concrete slab and external insulation d 2 23 flat roof with impermeable concrete slab and internal.
A concrete slab flat roof is normally made up of a structural layer of concrete finished with a smooth screed onto which a water proof layer such as a membrane is laid.
The blocks come in several sizes but this guide will assume you are using a 16 3 4 inch wide concrete slab.
Oct 4 2017 flat concrete roof construction details detail drawings.
Slabs are constructed to provide flat surfaces usually horizontal in building floors roofs bridges and other types of structures the slab may be supported by walls or by reinforced concrete beams usually cast monolithically with the slab or by structural steel beams or by columns or by the ground.
A solid slab of concrete capping the top of your house.
Because typical concrete is porous it needs to be treated with an additive such as xypex which makes the concrete waterproof.
Even though a treated concrete slab is waterproof standing water on a roof terrace should be avoided and so all roof terrace slabs should.
According to the 1995 aci code all two way reinforced concrete slab systems including edge supported slabs flat slabs and flat plates are to be analyzed and designed according to one unified method such as direct design method and equivalent frame method.
For example the florida based company hurricane proof systems offers a 7 inch 18 centimeter slab of concrete in three layers.
Exact specifications vary but most concrete roofs are several inches thick.
Hollow core concrete slabs paroc air is a simple and safe solution for making dry flat roofs.
Others would treat even steeper pitches as flat roofs.
The basis for this simple but effective solution is natural air pressure.
As the width of the concrete slab is 16 3 4 inches place the steel joists at this distance.
What is a slab.
Paroc air keeps the roof structure dry without any mechanical systems.