Flat roofs are common choices for commercial roofs and modern homes because of their neat, space-saving look. But many people think that flat roofs are completely flat, which isn’t true. Flat roofs actually need a slight slope. This small slope helps water drain away easily, stopping water from causing damage. Without it, roofs could develop leaks, structural issues, and age faster.
If you own property in Port Moody, where rain is common, it’s important to understand how flat roofing in Port Moody works. Knowing this helps you keep your roof strong and long-lasting. In this article, we’ll explain clearly why flat roofs need a slope. We’ll also discuss the best roofing materials like Torch-on roofing, TPO roofing, and EPDM roofing, and share helpful maintenance tips to protect your roof and your investment.
1. Flat Roofs Are Not Completely Flat
A common misunderstanding is that flat roofs are perfectly level. In fact, they’re built with a small slope—usually around ¼ inch per foot—to let water drain off easily (National Roofing Contractors Association, NRCA). Unlike steep roofs, which naturally help water run off, flat roofs depend on this slight angle to guide water toward drains.
If a flat roof were completely level, water would collect in low areas. This is called ponding, and it often leads to leaks and puts stress on the building structure. That’s why correct design and proper installation are so important, whether for commercial roofs or homes.
2. Why Flat Roofs Need a Slope for Drainage
Good drainage is one of the most important things for keeping a flat roof in good shape. If water has nowhere to go, it can sit on the roof and cause problems like:
- Leaks – Over time, standing water can seep through the roof, especially if it’s old or not well-maintained.
- Structural Damage – The weight of pooled water can put stress on the roof and weaken it.
- Mold and Algae Growth – Too much moisture creates the perfect spot for mold, which can spread inside the building.
To prevent these issues, roofers design flat roofs with proper drainage systems, such as:
- Internal drains – Common in big commercial roofs to move water off the roof.
- Gutters and downspouts – These help direct rainwater away from the building.
- Scuppers – Small openings on the roof edge that let water drain out.
A slight slope makes sure water flows toward these drainage points instead of sitting on the roof. If you’re looking for better ways to keep water off your roof, check out these 7 Effective Ways to Drain Water from Flat Roofing Systems.
3. Best Materials for Flat Roofing: TPO, EPDM, and Torch-On Roofing
Choosing the right material is key to making sure your flat roofs last a long time. Here are three popular and reliable materials:
TPO Roofing
- TPO roofing is made from a mix of rubber and plastic, making it strong against UV rays and heat.
- It has welded seams that create a strong, waterproof seal, lowering the chance of leaks.
- This type is great for commercial roofs because it saves energy and lasts many years.
EPDM Roofing
- EPDM roofing is made from synthetic rubber. It’s flexible and handles big temperature swings well.
- According to Wikipedia, if installed and cared for properly, EPDM roofing can last up to 50 years. This makes it a strong choice for both commercial roofs and homes with flat roofs.
Torch-On Roofing
- Torch-on roofing is very popular for flat roofing in Port Moody. It uses heat to apply asphalt membranes securely to the roof.
- It’s well-known for excellent waterproofing, making it ideal for rainy climates.
- Torch-on roofing is highly durable and resists damage well.
Each of these materials works best when used on flat roofs with the right slope, ensuring water drains properly and protects your property.
4. Common Problems With Poorly Sloped Flat Roofs
If a flat roofs doesn’t have the right slope, it can lead to several issues, including:
- Water pooling – When water sits too long, it puts extra pressure on the roof’s surface.
- Faster wear and tear – Sun exposure and trapped debris can break down roofing materials more quickly.
- Cracks and bubbles – Moisture that gets trapped under the surface can cause blisters and cracks.
- Higher repair costs – Poor drainage often leads to frequent fixes and a shorter roof lifespan.
In Port Moody, where heavy rain is common, making sure your flat roofing has the right slope from the start is key to avoiding these costly problems.
5. How to Keep Flat Roofs in Good Shape for Years
Regular maintenance is the best way to make flat roofs last longer. Here are some simple but important steps to keep your roof in great condition:
- Do regular checks – Look for pooling water, cracks, or any damage at least twice a year.
- Keep drains and gutters clear – Remove leaves and debris so water can flow properly.
- Reapply sealants when needed – Adding protective coatings helps strengthen the waterproof layer.
- Get professional inspections – A roofing expert can spot and fix small problems before they turn into big, expensive repairs.
Taking care of your flat roofing helps prevent water damage and keeps your roof strong for years to come.
Conclusion
Flat roofs might look simple, but they need to be built the right way to last. If they don’t have a slight slope, water can collect, leading to leaks, damage, and expensive repairs. Whether for commercial roofs or homes, having that small slope makes a huge difference in keeping your roof dry and in good shape.
The type of roofing material you use also matters. Options like TPO roofing, EPDM roofing, and Torch-on roofing are built to handle Port Moody’s rainy weather. But even the best materials won’t last forever without regular care. Cleaning your roof, checking for damage, and fixing small issues early can prevent bigger problems later.
If you’re thinking about flat roofing in Port Moody, it’s best to get advice from a professional. A skilled roofer can help you pick the right materials, install the roof properly, and give you tips on how to make it last. Taking care of your roof now means fewer worries and repairs in the future—so why not talk to an expert today?