Commercial roofing materials can be divided into two main categories: steep slope and low slope.
The first one includes watershedding types of roof coverings installed on slopes that exceed 14 degrees. On the other hand, low slope roofs include either weatherproof or waterproof types of membranes installed on slopes that are less or equal to 14 degrees (3:12).
Both systems come with a variety of coverings and components.
Steep Slope Roofs
Step slope roofing is further classified into six coverings. These are:
- Asphalt shingles
- Metal roof systems for steep slope applications
- Wood shakes and shingles
- Slate
- Clay and concrete tiles
- Synthetic
There are three parts to assembling a steep-slope roof:
- Roof deck – which is usually made of plywood, or some other wood-based material
- Underlayment – also known as ‘felt’ or ‘paper’, and it provides temporary protection until the covering is installed
- Roof covering – the external watershedding material
Low Slope Roofs
When it comes to low slope roofs, there are five different systems out there. These are:
- Metal panel roof systems for low slope applications
- Single-ply membranes, which are further separated into: thermoplastic (TPO and PVC) and thermoset (EPDM) membranes
- BUR, or built-up roof membranes
- Polymer-modified bitumen sheet membranes
- Spray polyurethane foam-based roof systems, or SPF
Low slope roof membranes, like their steep slope counterparts, also have three main components. These include:
- Weatherproofing layer(s) – this component keeps the water from entering the roof assembly
- Reinforcement – adds dimensional stability, strength and puncture resistance to the membrane
- Surfacing – protects the other two components from weather and sunlight, although some types also protect from hail, fire, solar reflectivity and so on.
Each of the two roofing systems (low and steep-slope) and their coverings come with a variety of advantages. To know more about them, contact us.
