In discussing flat roof pros and cons, we’ve covered vital details like an overview of flat roofs, general pros and cons, and the types of flat roofs, including their advantages and disadvantages.
Additional points discussed include flat roof maintenance, selecting the best type, and consulting the pros. Read along as we discuss these and other relevant points.
Pros and Cons of Flat Roof
Flat roofs have been around for millennia and have served various sheltering functions. Their relevance remains to this day. So, are you looking to have a flat roof for your structure?
This guide on flat roof pros and cons will help. Anyone embarking on a roofing project must know the basics, which helps with decision-making.
Flat Roofs Overview
While the name may suggest a flat roof, flat roofs are low-slope.
These generally have a ten-degree tilt or less to help with easy drain off of water. Flat roofs should never be completely flat, which could lead to improper water drainage.
These roofs typically come with 10 to 20-year warranties with the likelihood of extending their lifespans by five years or longer with proper installation and maintenance.
Slope roofs, as they’re also called, are commonly used on commercial buildings. Suitable materials and care are necessary for these roofs to serve their designed purpose.
This calls for professional installation and scheduled maintenance. Let’s discuss flat roofs’ general pros and cons before looking at the different types.
Flat Roof Pros and Cons
As expected, flat roofs have their advantages and disadvantages. This knowledge helps you weigh your options while selecting what serves your needs best.
Flat roofs are considerably cheaper than pitch roofs and can be installed within a shorter timeframe than other roof types with less disruption.
If you wish to install HVAC systems, flat roofs offer a holding place for these units.
What more? The space created by flat roofs can be used for various purposes, such as a recreational or relaxation spot, a rooftop garden, solar panel installation, etc.
On the other hand, flat roofs aren’t as stylish as other roof types. You may also be faced with performance issues like water seepage or leaks.
These can be problematic and lead to steady deterioration of the property.
Types of Flat Roofs | Advantages and Disadvantages
Having identified the general pros and cons of flat roofs, it’s time to take a closer look at the types available and the pros and cons of each.
Typical flat roofs include built-up roofing (BUR), modified bitumen, EPDM, TPO, SPF, and PVC. Having identified these flat roof types, let’s discuss their pros and cons as follows;
i. Built-Up Roofing
This flat roof type is designed with multiple layers of waterproof materials shielding roofs from UV rains and high winds. Layers include a reflective top coat, cover board, rigid insulation, asphalt, and ply sheets.
The pros of built-up roofing include UV resistance, fire resistance, regulation of thermal temperature, durability, seamlessness, and ability to withstand foot traffic.
Built-up roofs are also easy to repair and cost-effective. On the flip side, this roof type has cons, including releasing hazardous fumes during installation and difficulty identifying leaky areas.
The installation process is labor-intensive and can potentially support mold growth upon moisture penetration.
ii. Modified Bitumen
Comparing the pros and cons of modified bitumen can help you decide whether it’s suitable for your roofing project.
This flat roof type offers several advantages, like being easy to install and repair, plus offering high reflectivity and can be easily recycled.
Modified bitumen can also be used for residential buildings. Plus, it comes in various colors and styles.
Modified bitumen roofs are fire and UV-resistant and are also flexible. The drawdowns of having this type of flat roof include a relatively short lifespan, ranging between one and two decades.
Modified bitumen roofs won’t last long on roofs with heavy foot traffic and may be damaged upon exposure to significant debris and hail.
iii. EPDM (Ethylene Propylene Diene Monomer)
EPDM roofs are another type of material that can serve your roofing needs. How well you enjoy its utility depends on its pros and cons.
Pros include easy installation, the ability to withstand significant wind uplift, the ability to serve anywhere from 2 to 3 decades or more (with maintenance), being relatively affordable, and having reflective surfaces.
EPDM roofs have some drawdowns that include swelling upon contact with oils or oily substances, not as aesthetically appealing as other roofing materials, and could expand and contract with temperature change.
Leaks may occur due to delamination caused by exposure to moisture.
iv. TPO (Thermoplastic Polyolefin)
Flat roofs made of TPO material are energy-efficient and UV-resistant. They have other benefits that include high reflectivity, are a cost-effective option, and can be recycled.
Additional benefits of TPO roofs include resistance to dirt and corrosion buildup, multiple color and material options, and ease of installation and maintenance.
Regarding the pros, thermoplastic polyolefin roofs have a short lifespan of between 1 and 2 decades, might start as time goes on due to the seams, and may crack when subjected to foot traffic.
The quality of these roofs will depend on the manufacturer. This means the quality of the material isn’t standardized.
v. SPF (Spray Polyurethane Foam)
Spray polyurethane foam is a type of roof where liquid-applied systems seal up the top.
This flat roof type has several advantages, including being suitable for application on a variety of materials and also being easy to apply and fix.
SPF roofs are energy efficient and require low maintenance.
On the flip side, spray polyurethane foam roofs have their drawdowns with examples like their inability to perform against harsh conditions like wind-borne debris.
vi. PVC (Polyvinyl Chloride)
You can choose the PVC roofing option upon weighing the pros and cons and finding such to serve your construction needs.
The advantages of this material include its low maintenance requirement and long lifespan. PVC roofs are easy to install, lightweight, and seamless. Their highly reflective nature improves insulation.
PVC roofing material has its drawdown that includes steady deterioration with continued exposure to the elements. This causes brittleness in the material, which may lead to breaks and leaks.
There’s also shrinkage that may lead to leaks.
Now you know the pros and cons of flat roofs. We’ve discussed the general advantages and disadvantages of flat roofs and have proceeded to discuss the different types.