Key Drainage Considerations for New Building Construction

Drainage is a critical part of building design. When you're constructing buildings, roads, bridges, or other structures, it might seem like water systems should be an afterthought. However, it's crucial to design and decide on a building's drainage system before ever breaking ground.

Here's why. Water can cause a lot of damage if you don't have a plan for it. In the case of rain or significant flooding, water will pool. If water doesn't have anywhere to go, you're looking at potential foundation issues, erosion, sinkholes, and more.

Sure, those are worst-case scenarios. However, even a little water damage can cause mold, discoloration, cracking, and more – and no one wants that. That's why it's crucial to address a building's drainage options from the beginning.

How Drainage Works

As you'd expect, different types of drains work differently. However, all drains serve the same general purpose. Whether they're installed in a building or on a bridge, a drain's purpose is to remove excess surface water and allow it to flow to somewhere it won't cause damage. 

Often, drains will direct to beaches, creeks, rivers, or other water outlets to avoid damage to commercial property, homes, and land. However, that's not always the case. Sometimes, they simply slow down the water absorption rate so that the land has time to adjust without causing damage.

Different Drainage Options

There's no shortage of drainage options on the market. The right drainage system often depends on the building's needs. For instance, a food packaging warehouse is going to have more extensive drainage needs than an office.

The right one for your construction project depends on numerous factors, but here are the five most popular types of drainage systems.

• 1. Trench Drains – There are several types of drainage systems, but the most popular type is the grated trench drain system. Grated trench drain systems use a system of trenches and grates to move water toward an underground pipe. That pipe is usually sent to a water outlet or other accepted area for excess water.
• 2. Slot Drains – Slot drains work a lot like grated trench drains, except they don't need the grate. They have a slimmer design, so they generally go into the floor or ground without the need for a covering. Slot drains are a popular design for sanitary drains, which are commonly found in food preparation warehouses or other buildings that require top-tier sanitation. Slot drains and sanitary drains are usually made from stainless steel to avoid corrosion and bacteria build-up.
• 3. HDPE Drains – HDPE stands for high-density polyethylene drains. These drains are prefabricated systems. They work like trench drains, but you don't have to build them yourself. Instead, you simply put them in the ground and design around them.
• 4. French Drains – French drainage systems are for residential projects to redirect water away from landscaping and homes. These systems use a series of pipes to move water runoff away from the property and towards the sewage, swale, or cistern.
• 5. Swale Drainage System – Swale drainage systems are nothing more than a shallow ditch lined with grass (or other vegetation) to prevent puddling and flooding. Swale systems are used more for landscaping than for construction, but they're worth mentioning.

There are even more specific drainage system types within each of these primary drainage types. Ultimately, the right drainage system for your project depends on the project at large.

However, one thing remains clear. All these options need to be investigated and considered before beginning construction. We must have all of these options because just because one option works for a particular project doesn't mean it's a fit for another.

How to Decide Which Drainage Type is Right for Your Project?

How do you determine which drainage type is right for your project? In short, you'll want to do some engineering analysis. Take a look at the land's ability to naturally drain water and investigate the area's average annual rainfall. It's also important to consider other things like the building's purpose, the amount of traffic the drainage system will have to accommodate, and the altitude where the drainage system is going.

You'll also need to investigate the availability of water outlets and where other properties are sending their excess water.

After considering all these factors, you should be able to identify the right drainage type for your project. Just be sure to do it at the beginning of the design process instead of the end. Otherwise, you could be in for a lot of headaches down the road.

About the author - Skylar Ross is a contributor to the Innovative Materials blog. He is a content writer for the construction and home improvement industries with an interest in landscaping, outdoor remodeling, and interior design. Skylar is focused on educating homeowners, contractors, and architects on innovative materials and methods of construction that increase property value, improve sustainability, and create a warm and welcoming ambiance. You can reach him by email at innovativeflooringmaterials@gmail.com.