5 Best Ways To Soundproof Your Indoor Grow Room

13 Dec 2021

Discretion is essential when growing Cannabis indoors, and keeping the odor under control is just one part of being a successful grower with a secret garden. Controlling the amount of noise that is generated from lights, fans, pumps, and exhaust fans can be a huge difference maker in keeping your neighbors at bay, unwanted attention as well as the ultimate peace of mind. In this article we explain the 5 best ways to silence your indoor grow room and a top tip for each.

1. Acoustic Ducting

Anytime we ever set up an indoor grow room, ducting is always in the short list along with intake fans, exhaust fans, and carbon filters. The standard aluminium ducting that normally comes in sizes from 100mm - 250mm in diameter can be bought in different lengths and doesn’t cost too much to buy. Acoustic ducting is an upgraded version of the standard aluminium model and will be lined or cased with insulation. This foam allows for the noise of the air passing through the tubing at high speeds to become dramatically reduced. 

Using acoustic ducting can be initially an expensive investment and should be used for both intake and outtake fans. The cost can be almost triple the price of the standard aluminum version, however the return on investment is quickly gained as the ducting will stand the test of time and now you can focus on how to silence the noise generated by the intake and outtake fans.

Top Tip: When handling the acoustic ducting, be careful and wear gloves, a mask and eye protection as the material inside can be very irritating to the skin, and should not be inhaled.

2. Connecting SIlencers

If you are new to growing Cannabis indoors, you may find the noise levels when your outtake fan is on 24 hours a day can be very loud. Another great way to reduce the output of the noise is to use silencers which can be connected to ducting or the ends of the exhaust fan. Silencers are around 2-3 feet in size and are designed to muffle the noise of the passing air. An indoor grow room that uses silencers will notice the noise levels are far quieter than without. Connecting multiple silencers will seriously reduce sound and are very easy to set up, connect, and will last a long time.

In order to get the most effective sound reduction, try using silencers connected to the ends of the exhaust fan and acoustic ducting together. You will be amazed at how much of a difference this makes and how the industrial bass whirring sound is now almost nonexistent.

Top Tip: Using 2 of the same-sized silencers and connecting one to each side of the RVK exhaust fan is the most effective way to use silencers. They may also be connected to standard ducting or acoustic ducting if more practical when growing Cannabis indoors.


An example of heatsink cooling
An example of heatsink cooling

3. Digital Fan Controllers

The recent rise of digital fan controllers changed the way that an indoor grow room could be set up, with total control in the hands of the grower. These outtake fans are designed to be used with a controller that allows the grower to reduce or increase the amount of air being blown out. The advantages of this are noise levels can be reduced without losing too much power and they are great to use with different tent sizes as the air being exhausted can be changed at will.

The only downside to a digital fan controller is the cost, and they can range from Є300-Є600 in some cases. Probably not ideal for the beginner grower, however for the more experienced person, investing in a digital fan controller is well worth it as it can give you the upper hand when it comes to instantly reducing that industrial-sounding whirring.

Top Tip: If you use silencers, acoustic ducting and a digital fan controller together, then the results will be excellent with little opportunity for the exhausted air to make any unwanted sounds. 

4. Heat Sink Lighting 

Grow lights are normally at the top of the list to buy when setting up an indoor grow room. 

Nowadays there are many different types of horticultural lighting that can be used to grow Cannabis, and the most recent are those which incorporate heat-sink technology. SANlight is a perfect example of how LED lights can be used when growing Cannabis without the need for internal cooling fans. 

The heat-sink design allows heat to be transferred away from the light and towards the upper part of the grow room and means a totally silent grow light. There is no need for a buzzing ballast that can get extremely hot, or is there the need for internal fans that become noisy and dusty over time. Furthermore, when one of these internal fans breaks down in some existing LED lights, the opportunity to repair and replace the fan instantly is almost impossible causing the grower to buy a new light which may be inconvenient. 

Top Tip: Heat sink lighting is becoming more popular when growing Cannabis and internal fans are now quite outdated and can be problematic over time. 



This grower uses a wooden acoustic box and a silencer.
This grower uses a wooden acoustic box and a silencer.

5. Acoustic Wooden Boxes

Basically a wooden box designed to house the RVK exhaust fan, that is lined with sound-proof material. Once the exhaust fan is sat inside, the ducting will emerge from each side of the wooden box. The principle behind this is to absorb the sound waves made by the loud exhaust fans, allowing an indoor grower to reduce the original noise output down by around 75% less. 

The only downside to using these heavy wooden acoustic boxes is that they will need to be sitting flat on the floor, or securely resting outside on the top of your grow tent. Combined with acoustic ducting and silencers, these wooden boxes work a treat and can turn your indoor grow room to the ultimate secret garden that is both smell proof and sound proof!

Top Tip: Hanging the wooden box inside your tent or from the ceiling of your indoor grow room can be hard work, take up vital space, and be impractical in the event of an emergency. 

What Else To Consider

  • Air Pumps: When growing Cannabis with hydroponics, air pumps can be noisy and vibrate through the floorboards. Use a foam cushion to sit the air pumps on to reduce the reverberation. Building a soundproof box the pump can sit is may be a good idea also. 
  • Mounted Fans: Think twice about installing your wall fans and clip on fans, especially if you live close to your next-door neighbors. The constant humming noise can drive a neighbor crazy and cause a knock on the door. Make sure the fans don’t vibrate and cannot be heard.
  • Rapport with Neighbors: It may not always be ideal in some cases, however keeping a good rapport can help you keep a low profile. It is also the neighbors who will approach you if they are suffering with noise created through the walls or floorboards.