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✓ Use of own staff
✓ 3-month guarantee
✓ Fixed rate, no hourly rate
Call us at 085 303 9999
✓ Fixed price
✓ No call-out fees
✓ 3-month warranty

Drain flies, also known as moth flies or filter flies, are small insects often found in and around homes. These tiny but persistent insects can be a major nuisance in both households and businesses. They often indicate underlying issues with your drainage or sewage system. Read on to discover how you can get rid of drain flies for good!
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A drain fly is a type of mosquito. It is also known by other names, such as moth fly or filter fly. They belong to the Psychodidae family and are known for their hairy wings and moth-like appearance. Adult flies are typically 1.5 to 5 millimeters in size and have a grey or light brown color. They are often seen in damp and dark environments, such as bathrooms, kitchens, and basements.
Drain flies are primarily attracted to damp and decaying organic materials. They thrive in wet and contaminated environments where organic waste accumulates. This can include:
The most common breeding grounds for drain flies are sewer pipes and drains that are clogged or partially clogged. Additionally, a broken sewer pipe, which causes undetected leaks, can also provide an ideal environment for these flies to develop.
In poorly maintained septic systems, drain flies can multiply rapidly.
Food scraps and other organic material in clogged sinks can attract drain flies.
Leaks or high humidity levels in basements and crawl spaces provide an ideal environment for drain flies to breed.
Leaks or high humidity levels in basements and crawl spaces provide an ideal environment for drain flies to breed.
To determine if you have a drain fly problem, there are several signs to look out for. Firstly, you'll often see small, moth-like flies around drains, sinks, showers, and bathtubs. Additionally, a strong, unpleasant odor coming from drains and sewers can indicate the presence of organic material that attracts drain flies. You might also find small larvae or pupae near damp areas, such as under sinks or in shower drains. If you regularly experience slow-draining water, this could point to a partial blockage where drain flies lay their eggs. By recognizing these signs early, you can quickly take action to combat a potential infestation.

When the cause of drain flies is known, such as a break or a blockage, we can proceed directly with repairs. If the source is unclear, we use our smoke detection service. For a fixed price, we blow non-toxic smoke through your sewage system to identify all possible cracks and openings where flies might be coming from. This thorough inspection ensures that no problem is overlooked, making your sewage system fully functional again.
Our rates are fixed and transparent. This means there are no additional costs, no matter how long the job takes. You won't face any unexpected surprises.
Local blockages
Toilet, shower, sink, drain, basin, washing machine
Unclogging the main line
Unclogging using high pressure + camera inspection
Sewer inspection with camera
Checking for problems such as leaks or cracks
Smoke detection for sewer system
Tracing the cause of sewer odor
Smoke detection & camera inspection
Mapping the piping system using smoke detection and camera inspection
Combatting Drain Flies
Professional and thorough approach to the sewer fly problem
€165 incl. VAT
€296 incl. VAT
€180 incl. VAT
€180 incl. VAT
€220 incl. VAT
Price on request
✔ Fixed rate, no hourly fee
✔ 3 months warranty
✔ No call-out charges
✔ Fixed rate, no hourly fee
✔ 3 months warranty
✔ No call-out charges
For unusual working hours, surcharges apply. See here the working hours and the rates and surcharges that apply to the mentioned working hours:
On the following days, normal rates apply:
– weekdays from 08:00 to 18:00
On the following days, a 50% surcharge applies:
– weekdays from 18:00 to 00:00
– Saturday from 08:00 to 18:00
On the following days, a 100% surcharge applies:
– all days from 00:00 to 08:00
– Saturday from 18:00 to 00:00
– Sundays and public holidays
Recognizing drain flies is important for taking quick action. Here are some characteristics of these insects:

The first step in combating drain flies is thorough cleaning. Ensure that all potential breeding grounds are cleaned and disinfected:
Use a drain cleaner to remove grease, dirt, and organic material from the drains. This will eliminate the larvae's breeding grounds. Next, improve ventilation in damp areas like bathrooms and basements to reduce humidity. Regularly clean under appliances such as refrigerators and dishwashers where moisture can accumulate.
Various types of traps can help reduce adult drain flies. Place sticky traps near damp areas and drains to catch the adult flies. You can also fill a bowl with a mixture of water, vinegar, and a few drops of dish soap. This will attract and drown the flies.
Smoke detection is an effective method for quickly and accurately identifying problems in the sewage system. Smoke detection in the sewer works by using special equipment that injects non-toxic smoke into the entire sewage system. The smoke spreads throughout the sewer network. Any leaks, holes, or poorly connected joints in the system become visible as the smoke escapes from those points. Rioolbeheer Nederland's technicians follow the smoke and inspect the areas where it emerges. In most cases, the technicians can resolve the issue immediately. After the inspection, a report is prepared documenting the findings. This report helps in planning any necessary repairs and improving the sewage system.
In some cases, chemical pesticides may be necessary to combat a severe infestation. Use insecticides specifically designed to kill drain flies. Follow the label instructions carefully to maximize effectiveness and ensure safety. There are also specific drain cleaners available that not only clean drains but also kill insects hiding within them.
Need help combating drain flies? RBNL is here for you. You can count on our fast and friendly service, 24 hours a day, 7 days a week. Our certified professionals will not leave until your sewage problem is completely resolved. Make an appointment by phone or via our website and let us take care of your problem worry-free.
Drain flies? No plumbing job is too big or too small. Contact us today!
Prevent future drain fly problems by taking some preventive measures after treatment. Ensure regular maintenance by keeping drains and sewers clean with drain cleaners. Additionally, control the humidity in your home by applying good ventilation and moisture control, making living conditions unfavorable for drain flies. Finally, repair leaky faucets, pipes, and other water sources to reduce damp environments and prevent future infestations.

Your home or work comfort is our priority!
While it is possible to take steps yourself to combat drain flies, calling in a specialist can often be the most effective and lasting solution. RBNL is your reliable partner for professional drain fly control. Our certified specialists have the knowledge and experience to quickly identify and eliminate the source of the infestation. Using advanced techniques and environmentally friendly methods, we ensure that your home is free from these annoying insects again.
Call us today or make an appointment online to solve your drain fly problem for good. We guarantee a professional and thorough approach, so you can enjoy a clean and hygienic home with peace of mind.
Drain flies are attracted to damp environments and organic matter, such as rotting food and waste, found in drains and sewers.
While drain flies themselves are not harmful to humans, they can transmit diseases and cause allergic reactions if present in large numbers.
If you see drain flies, thoroughly clean all drains and check for blockages. Using drain cleaners to remove organic material can also help.
No, drain flies do not bite. They are more of a nuisance than a direct danger.
If you are still bothered by drain flies despite cleaning and preventive measures, it is advisable to call a professional like RBNL for a thorough and effective solution.
The life cycle of a drain fly, from egg to adult insect, lasts approximately 1 to 3 weeks. Adult drain flies typically live for a few days to a week.
To prevent an infestation, it's important to keep drains and sewers clean, repair leaks, and minimize damp environments through good ventilation.
It is recommended to thoroughly clean your drains at least once a month to prevent the buildup of organic material that attracts drain flies.
Drain flies keep returning if there are still damp and organically rich environments where they can feed and reproduce. Ensure thorough cleaning and maintenance to prevent recurrence.

Rioolbeheer Nederland specializes in unclogging, cleaning, inspecting, and locating sewers, drains, and pipes. Your satisfaction is our goal. Customer satisfaction is of paramount importance to us.



Locations
Contact
Tel: 085 303 9999
Address:
Amsterdam Address:
Jacob van Lennepkade 151 H
1054 ZL Amsterdam
Utrecht Bilthoven Address:
PC Staalweg 60
3721 TJ Bilthoven
Email address: info@rbnl.nl
Chamber of Commerce: 87133989



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