Vertical and scupper drains form a complete flat roof drainage system. These drains let ponding water on a flat roof drain off before it causes damage. The correct type of vertical drain depends on the flat roofing membrane, the type of drain insert, and whether the deck accommodates a lot of foot traffic.

(NOTE: Scupper drains are part of any appropriate drainage system for flat roofs, but they’re outside this article’s scope. Scupper drains direct water runoff laterally, through a parapet wall or curb, rather than downward like vertical drains. Read our article about scupper drains here).

Vertical Drains for Flat Roofs

Vertical drains (sometimes called interior drains) have three recognizable features:

  1. Its flange facilitates sealing and fixing onto the flat roof surface.
  2. It connects to the DWV (drain-waste-vent) system below the deck.
  3. It has a strainer, preferably made of die-cast metal. The strainer prevents debris, leaves, and wildlife from clogging the drain and causing standing water to pool.

Menzies Metal Products offers a variety of copper and aluminum vertical drains to suit any desired look, including our two mainstays: the Clamp-Tite Spun Copper Drain and the Clamp-Tite Spun Aluminum Drain.

Clamp-Tite Spun Copper Drain by Menzies. Clamp-Tite Spun Aluminum Drain by Menzies. Flat roof drains are also sometimes called interior drains.

Most Menzies Metal Products flat roof drains also come in a TPO Direct Weld™ variety for TPO roofs.

For Flat Roofs With Existing Shallow Bowl Drains

Some re-roofing and roof replacement projects may force you to work with existing flat roof drainage systems that are not ideal. For instance, some drains may have shallow bowls that won’t accommodate the two standard vertical drains above. In such cases, we recommend the following Menzies Metal Product vertical drains to fix the problem:

Clamp-Tite Spun Copper Drain Small Bowl by Menzies, meant to be used on existing vertical drains with shallow bowls.
Clamp-Tite Spun Aluminum Drain Small Bowl by Menzies, the aluminum alternative.

Menzies strongly recommends including Menzies Metal’s Blue Drain Seal™ at the hub for the drains mentioned above. The Blue Seal prevents any water backup from seeping into the building structure and causing damage. We’ll discuss more about it later in this article.

For Projects Requiring Mechanical Connections

The installation process for the flat roof drains we have covered so far is to insert them into a standard DWV pipe and fix them with the Blue Drain Seal™ at the hub. However, if the project requires a mechanical connection to the DWV pipe, our Clamp-Tite Spun Copper Drain without hub is the way to go.

Clamp-Tite Spun Copper Drain No Hub by Menzies, which accommodates mechanical connections to drainage systems.

To Replace Existing Drains in Re-Roofing Applications

In case you work with an existing flat roof drainage system, you may find some old drains empty into an insert pipe with a smaller diameter than the rest of the DWV system. In such cases, use the Commercial Undersize Aluminum Drain.

Commercial Undersize Aluminum Drain by Menzies, with a smaller-diameter pipe for use as an insert drain in a re-roof application. Not compatible with Menzies’ Blue Drain Seal™.

Budget Friendly Options

Other flat roof drainage projects may need to be done on a tight budget. At Menzies Metal Products, we’ve got you covered with more economical options to choose from: The Commercial Spun Copper Drain and the Spun Aluminum Value Drain.

Commercial Spun Copper Drain by Menzies. It’s similar to standard vertical drains but without the clamping ring to secure the drain to the membrane more firmly.
Spun Aluminum Value Drain by Menzies.

For Roof Overhangs

Menzies Metals also has two vertical drains for overhangs, which can drain water from a flat roof without the need for strainers:

Econo Copper Drain by Menzies is for use on overhangs.
Econo Aluminum Drain by Menzies.

Vertical Drains for Areas With Foot Traffic

When a flat roof accommodates a lot of foot traffic (like commercial buildings and roof decks with an outdoor living space), the drain openings must have strainers that run flush with the roof’s surface to prevent accidents. Menzies Metals has four standard products to provide proper drainage for such areas:

Spun Copper Deck Drain by Menzies, flush for pedestrian areas.
Clamp-Tite Aluminum Flat Top Drain With Bowl by Menzies for foot traffic areas on concrete substrate.

Koala Deck Drain by Menzies.
Koala Drain PVC by Menzies.

Pedestrian Area Drains Requiring Mechanical Connections

If your pedestrian area drains require mechanical connections below the deck, Menzies Metals also has you covered with the following products:

The attachment drain coupler is sold separately.


Koala Deck Drain No Hub PVC by Menzies. Attachment drain coupler is sold separately.

Koala Deck Drain No Hub by Menzies, made of aluminum. Attachment drain coupler sold separately.

For Concrete Core Drills

Sometimes, a flat concrete roof may require new drains cored through the concrete. As the new drain hole will have no bowls, we recommend using the Clamp-Tite Aluminum Flat Top Drain No Bowl.

Clamp-Tite Aluminum Flat Top Drain No Bowl by Menzies, for areas with foot traffic. Its flat-bottom, no-bowl construction is meant to accommodate cored holes through concrete.

Blue Drain Seal™ by Menzies Metal

For flat roof drainage systems with vertical drains whose stems will go into drain inserts, we suggest using Menzies’ Blue Drain Seals™ to secure each connection with the DWV system.

Blue Drain Seal™ by Menzies prevents water back-up damage when using drain inserts.

Without Menzies Metal’s Blue Drain Seal™, water back-up (in cases of a clogged drain) can seep into the surrounding structure and cause damage.

Without Menzies’ Blue Drain Seal™, water can back up and cause damage.

With Menzies Metal’s Blue Drain Seal™ properly installed, the surrounding structure will stay dry even in the event of a clogged drain.

Menzies’ Blue Drain Seal™ creates a water-tight seal between the insert drain and the vertical drain pipe, preventing water back-up.

Installing Menzies’ Blue Drain Seal™ will require our special 24” screwdriver, free when purchased with six or more Blue Drain Seals™.

 

Other Vertical Drain Accessories

When undersized drains need to connect to larger-diameter DWV pipes, we recommend using the Undersize Drain Coupler by Menzies Metals to ensure a proper seal and connection with the pipe system.

Undersize Drain Coupler by Menzies. Used to connect undersized drains to standard DWV plumbing pipes.

Menzies also has you covered with those damaged strainers on your inner drains.

When strainers become damaged or deteriorate for any reason, Menzies Metal also offers high-quality Replacement Die Cast Strainers, which fit a variety of drains under the Menzies brand.

Replacement Die Cast Strainer by Menzies. Fits all of Menzies’ strainer-style vertical drains.

Trust Menzies Metal Products for All Your Vertical Drain Needs

Menzies Metal Products has been a trusted name in proper flat roof drainage solutions since 1978. Whether your flat roof is membrane, TPO, or concrete, we have the right drain products and roofing professionals to ensure proper drainage and keep it in peak condition.

Check out our extensive catalog for detailed information on all our products for your vertical drain needs and other flat roof drainage system requirements