Solar Powered Roof Pump: Everything You Need To Know About

Have the thought of installing a solar-powered roof pump crossed your mind? Please don’t let it go down the drain.

The sun is a free natural source of energy and tapping into it means lots of saving. Solar roof pumping refers to the use of solar energy to power a pump than using it to remove water that accumulates on roofs.

To choose a good solar-powered roof pump, you must factor in some considerations such as size, pumping rate, performance, functionality, durability, cost, etc.

With the right solar roof pump, you don’t need to go through the nail-biting and expensive task of installing in-roof drains. If you have a flat roof, the ponding water problem will also be a thing of the past.

We’ve done thorough research and compiled all the crucial information you need to know about solar-powered roof pumps.

You can be assured that this is the information resource you need to know what solar-powered roof pump to buy and how to get started with this brilliant project.

What is a Solar-Powered Roof Pump and How Does it Work?

A solar-powered roof pump is a technologically advanced device that harnesses the sun's energy and uses it to pump ponding water off roofs.

Usually, the pumping system comprises of three main components:

  • A solar panel,
  • A battery,
  • The pump.

The solar panel collects the solar energy and converts it to the energy that runs the pump on demand or stored in the battery for backup. The battery will, in most units, have a digital chip for precise charging.

The pump is a high-tech device that removes water when it accumulates to a certain level on your roof. Some solar roof pumps will come with the siphon feature that removes the water even when the battery is out of power.

A garden hose or PVC is attached to the pump to carry the ponding water off the roof.

The primary goal of solar-powered roof pumps is to offer a cost-effective solution for ponding water on roofs.

The pumps are a perfect alternative for the expensive in-roof drain installation, roof renovations/repairs.

Common causes of ponding water on roofs include:

  • Malfunctioning roof water diverters
  • Blocked roof drain filter, and
  • Sagging/clogged overflow drains or downpipes.

Regardless of the cause of water accumulating on your roof, a solar roof pump is the best solution for the water.

How do Solar-Powered Roof Pumps Compare to Conventional Roof Pumps?

FactorSolar-Powered Roof PumpsConventional Roof Pumps
Source of powerSun’s energyFossils fuels or electricity
Fuel costNo fuel costHigh fuel costs
InstallationSimpleCan be complicated if several connections are needed
Good with basic frequent inspectionsRequires more focused maintenance
Upfront costPotentially highModerate
Cost-effectivenessVery cost-effective in the long run  High cost due to the pricey fuels
Pumping capacityRelatively lower, especially when there’s no sunHigh when power or fuels are supplied uninterruptedly
ReliabilityReliable when coupled up with a backup batteryAnnoying fuel supply limitations

How to Choose the Best Solar-Powered Roof Pump?

If you want to pick the best solar-powered roof pumps, you need to evaluate your needs and then check if the pump you’re looking to buy conforms to those needs.

Here’re some questions you can ask yourself to get started:

  • How deep is my roof structure?
  • What’s the surface area of my roof?
  • If storms so harsh in my area?
  • Is ponding a common problem for my roof?
  • What’s my budget?

On finding answers to these questions, here are the crucial specs you should be targeting and the recommendation for each.

PerformanceThis is how well a solar roof pump works to pump ponding weatherA 20-watt solar pump is enough to sort out ponding water on a standard roof. Cold weather protection adds to the performance
Pumping rateThe pumping rate is the amount of water the unit can pump per unit time.

The pump rate is expressed in Gallons Per Minute (GPM) for solar roof pump and is calculated as follows:

GPM= Gallons of water pumped/ hours taken × 1 hour ×60
If you need a solar pump to remove 900 gallons of water from a roof in 5 hours, then its GPM should be

900/ 5hours × 1 hour ×60 = 3GPM
Backup batteries
A backup battery provides power to run the pump when there’s insufficient energy direct from the solar panel.Go for units with a backup battery if you need to pump water continuously, even during cold weather.
Charging time

If you have a battery, you can charge it when there’s sufficient sun. The charging time is directly proportional to the capacity of the battery that you have.Choose a solar roof pumping unit whose solar panel can charge a 12V battery is not more than 8 hours.

Size and weightThe size and weight of the solar roof pumping system depend on the dimension of individual components.Lightweight but functional pumps are preferred to the heavier varieties since this makes installation, maintenance, and storage effortless.
Suction depthThis is the maximum water level at which the solar roof pump will operate.Most solar roof clearance pumps will handle at least 1 foot, so anything below this is not recommendable. If you can find a pump that works for your specific flat roof depth, the better.
Extra featuresThese are accessories that improve the experience of using a solar roof pump.Target a solar roof pump with a good number of additional features such as LED lighting and automatic control, as long as the overall cost is sensible for its main role.

How Much Does Solar-Powered Roof Pump Cost?

Cost is a crucial consideration when it comes to choosing a good solar-powered roof pump. Even if you find a pump that meets the above criteria, it’ll still trickle down to what you can afford.

Many retail solar-powered roofs pump retail at $500-$1000 depending on the features it comes with.

For the best deal, compare several solar roof pumps and settle for the one that’s reasonably priced.

If you’re buying from an online store, you should delegate some amount for shipping.

Solar-Powered Roof Pump Installation

The installation of a solar roof pump is pretty straightforward.

Here’s the simple procedure:

  • The pump is set in the deepest spot of the ponding area.
  • The solar panel is installed in a place where there’s plenty of sunlight
  • An electrical connection from the solar panel to the pump is made (If charging is needed, the connection is made to the battery)
  • PVC piping is connected and runs 5-6 feet below the roofline, ready to pump water off the roof.

Who should install the solar roof pump?

To install the roof pump properly, you may need to work with a roofing contractor and licensed plumber.

However, most solar roof pumps sellers will offer installations services and/or guidance on fixing when you need the pump and removal when it’s time to store it.

What is the Lifespan of a Solar-Powered Roof Pump?

For this mechanical equipment, you should expect around 15-20 years of service. This, however, depends on the following:

The quality of the unit: Install premium solar roof pumps as they’ll serve you for long

How the installation was done: The pumping unit needs to be installed properly to serve you for long

Care and maintenance have given: A properly maintained solar roof pump will clock its expected lifespan. Check out our recommendations for this below.

Maintaining Your Solar-Powered Roof Pump

Grinding weather conditions can hit hard on any mechanical equipment installed outdoors. Impressively, most solar-powered roof pumps available in the market are sturdy enough to withstand even the harshest weather conditions.

However, it’s crucial to inspect your solar roof pump after every storm. During the inspection, you need to ensure that:

  • The solar roof pump is positioned properly
  • All the components of the solar pump are intact
  • The drains lines are fine

When the weather is favorable, you can remove the solar roof pump and store it properly until the next rainy season.

Benefits & Drawbacks of Solar-Powered Roof Pumps


Wondering why it’s so crucial to install solar roof pumps? Let’s have a look at their benefits:

Prevents collapse of the roof structure

Ponding water weighs around 5lbs. per foot (depth), per square foot of a roof’s surface. A 10’ by10’ roof surface at 1’’ deep (100 square feet) would carry 1000lbs of live weight of ponding water.

With this additional weight, not forgetting the weight of the debris such as mud and algae attracted by the water, roof structure failure/collapse can occur anytime. A solar roof pump eliminates all this trouble.

Eliminates health risks

Ponding water, if left unattended on the roof, may facilitate the growth of algae. This, in addition to droppings from roof-dwelling animals, may cause a host of health problems. The major health risk is the reduction of the quality of air in your building.


A solar roof pump is always available to remove ponding water on your roof, even when there’s a power outage. Some work even when the battery loses charge as a siphoning system to continuously remove the pond water.


From reducing your energy bills to eliminating costly maintenance/ need for roof structure renovation in case of damage, solar-powered pumps stand out to be the most cost-effective solution for ponding water solutions.

Easy to install and maintain

As seen above, a solar roof pump can be installed in under 15 minutes by a qualified solar technician. Even better, little to no maintenance is required for these units.


Here are the disadvantages of solar roof pumps that you should know before making a purchasing decision:

Not a primary way to drain your roof

Solar roof pumps are just a backup to remove ponding water when there’s a problem with the drainage.

This simply means that installing the unit does not exempt you from ensuring that your roof drainage system is working all the time.

Limited to certain roof depths

Most solar roof pumps will have a limitation for the roof depth they can pump the water from.

Even so, you can always invest in several solar pumps to provide power that matches your pumping needs.

Low versatility

Generally, automatic solar pumps may only work for ponding water on roofs. In this regard, you may still need to invest in a utility pump if you have other pumping needs in your establishment.

Do solar-powered roof pumps work on cloudy/ rainy days?

Solar-powered roof pumps come with a battery that stores energy to be used when the weather is harsh.

Most solar pumps will work for a given period in the rainy depending on the capacity of the backup battery and the power stored when the sun was up and shining.

The siphoning function adds to the functionality of a pump during cloudy and rainy days, so it’s something you need to consider when buying your pump.

Are they chargeable from the plug or have backup power?

Most solar roof pumps will use power directly from the solar panel, but there’s an option of having a backup battery.

The battery can be charged when there’s plenty of sun, then used when the weather is relatively unfavorable.

Can I install a solar roof pump on my own?

Yes, if you follow the guidelines for the unit to the letter. In most cases, an inexperienced person will still make some mistakes and that’s why it’s recommended to work with licensed roofers.

Moreover, if you’re dealing with a hard-to-access roof, you better leave the work to professionals to reduce the associated work dangers.

Wrapping up

For flat roofs, ponding water is a real threat that comes tied with problems such as damaging leaks or, worst, collapse due to the weight of the ponding water. Considering this, a ponding roof is not something you would want to overlook.

For a long time, the solutions for ponding in roofs have been limited to the pricey re-decking, re-pitching, re-roofing, or installation of in-roof drains.

However, with a good solar-powered roof pump, you can now remove ponding water from your residential or commercial property’s roof cost-effectively and conveniently.

No hard and fixed rule dictates what solar-powered roof pump should be installed for a particular property.

So, just assess your needs following the tips and strategies discussed here and you’ll have a solar roof pumping system that you can rely on.