Short answer. Scuppers in Dallas are openings through a parapet wall that let water off a flat roof into a conductor head, a box that funnels it into a downspout. We size scuppers and downspouts to the roof area, seal them into the wall and roof membrane, and add overflow scuppers as a backup if the main drain clogs.
How flat roofs drain
A flat or low-slope roof inside a parapet has to get water out through the wall or down through interior drains. Scuppers are the through-wall route: a lined opening at the low point of the roof, with a conductor head on the outside wall to catch the water and feed a downspout.
When a scupper is too small, clogged or badly sealed, water ponds on the roof and finds its way into the building. That is why we look at the roof slope and membrane, not just the metal, and why clogged scuppers are part of our commercial cleaning visits.
Scupper, roof drain or edge gutter?
| Scupper and conductor head | Interior roof drain | Edge gutter | |
|---|---|---|---|
| Used on | Flat roofs with parapets | Flat roofs without edge access | Sloped roofs and some low-slope edges |
| Water leaves | Through the wall | Down through the building | Over the eave into a trough |
| Easy to inspect | Yes, from outside | Needs roof access | Yes |
| Backup | Overflow scupper | Overflow drain or scupper | Larger outlets |
What drives the cost of scupper work
We have no sourced price range for scuppers, so these are the factors that set yours.
- 1New opening or replacement
Cutting a new wall opening takes far more work.
- 2Material
Copper heads cost more than aluminum.
- 3Size
Larger roof areas need larger scuppers and downspouts.
- 4Membrane work
Sealing into the roof membrane, often with your roofer.
- 5Access
Lift or roof access on taller buildings.
Through-wall scuppers
The scupper itself is a lined metal opening through the parapet at the roof's low point. It has to tie into the roofing membrane so water cannot get around it into the wall. We size the opening to the roof area it drains and fit it with flanges that the roofer can seal into the membrane.
Conductor heads
A conductor head is the collector box on the outside wall that catches water leaving the scupper and drops it into the downspout. It slows the flow so the downspout does not choke, and it can be a plain box or a decorative one on older buildings. We match the head and downspout size to the scupper.
Overflow scuppers
If the main scupper or an interior drain clogs, water keeps rising on the roof. An overflow scupper set slightly higher gives it a way out before it backs up under flashing or over the parapet. Many codes expect secondary drainage on flat roofs, and it is the cheapest insurance a flat roof can have.
Sizing to the roof
The roof area each scupper drains decides its size and the size of the downspout below it. Undersized parts are a common reason flat roofs pond in heavy Dallas rain. We measure the drainage area before choosing parts rather than copying the old ones.
Scupper parts formed in Dallas
Dallas suppliers stock seamless gutter coil in aluminum, copper and Galvalume, so conductor heads and downspouts can be made to match the building rather than ordered in one stock finish. That matters on older commercial and parapet-roofed buildings, where a copper head can match original trim and a plain aluminum box would look out of place. We match the metal to the building before ordering anything.
How long scupper work takes
Replacing a conductor head and downspout is often a few hours. A new through-wall scupper takes longer because the wall is opened and the membrane must be sealed around it, usually with the roofer, so plan on a day or more per opening. We give the timeline after seeing the roof.
How scupper work goes
Look at the roof
Slope, low points, membrane and existing drains.
Size the parts
Scupper, head and downspout matched to the drainage area.
Open and set
Opening lined and flanged for the membrane.
Seal
Membrane sealed around the scupper with the roofer.
Head and downspout
Collector box and downspout hung and tested.
Scupper and conductor head questions
An opening through a parapet wall that lets water off a flat roof.
The collector box under a scupper that funnels water into the downspout.
Often a clogged or undersized scupper, or a low spot that does not reach it.
On most flat roofs it is a smart backup in case the main drain clogs.
Yes. Scuppers must be sealed into the membrane, so we coordinate.
Yes, as part of commercial gutter cleaning.