DIY Clean Air Flow-Hood

Efficient, cheap & fiberglass-FREE flow-hood buildup  – 3 kinds to pick from

86:62 mins.

38:46 mins.

 4 Quizzes



The Flow-hood Basics

There are some things that you’ll have to know before starting to build a clean air flow-hood. This section explains you how to match a blower to a filter size, what kind of blowers and filters you should pick and why, and teaches you how to check your newly build flow-hood’s efficiency. 

Also get you a picture about the commercial flow-hoods out there and compares them.

Step-by-Step Details
DIY 2 Flow-hoods

This part shows you via movies and presentation how to build a low-cost card-board flow-hood (cost = $70-$100).

The second part of this section shows you how to build a low-cost ply-wood flow-hood (cost = $150-$185).

Both, are great for fungus tissue transfers, spawn production or other mycological applications, microbiology, electronics, plant tissue, robotics, etc.

DIY Recycled Clean Air Flow-hood

This part will give you instructions on how to build a recycled clean air flow-hood. 

This is a flow-hood type that requires a bit more investments (over $250) but it’s a great addition to a lab. 

You’ll also learn about the structure of this kind of flow-hood its air current dynamics, and how to calculate it’s air flow rate.

Take a Closer Look

In 2010 I built my first flow-hood because I didn’t have 500 bucks to buy one. So, I built a partially recycled clean air flow-hood (see the picture below). This was an efficient flow-hood and I used it for a while. The only downside of it was the filter which was a fiberglass made filter. -these are standard HEPA filters usually used by the industry. Practically every flow-hood that you see has a fiberglass filter.

Recycled clean air flow-hood
Clean air flow-hood made out of plywood

In 2013 I built my second flow-hood that I used for about a year. This was a simple, cheap flow-hood that I was very proud of, once again the only downside of it was the filter glass. So, what’s the deal with fiberglass? Well..some people care some don’t care about.. their own health. One day by mistake I checked one of the cultures under the microscope and I saw some sharp fragments spread all over the microscope slide, then I took a sample from inside the flow-hood that I was using and suddenly I realized that the HEPA filter was spreading these fiberglass particles all over. I got them everywhere on my hands, cloths, door handles etc. They were always shiny against the light -you can see this when handling Petri plates and then, if you check your palms against sunlight you’ll see tiny sparkles. I was eating with those hands and I was breathing the air that came out of these flow-hoods. So, next I decided to build a third flow-hood which should have no fiberglass in it -which I did.

The third flow-hood that I’ve built (see top of the page) in 2015 was made out of a cardboard box and is a really low-tech equipment but efficient and has no fiberglass in it. Instead of a HEPA I used conventional home clean air filters. The way I design them it works and that’s what matters!

Clean air workbench made of hardwood material
Next I built a forth flow-hood using hardwood as building material, another efficient and cheap valuable clean air workstation that does the job and I don’t have to worry about hazardous fiberglass particles anymore. So, if you need reliable step-by-step instructions on how to build one of these babies this is the right course for you. It is information rich and comes with video recordings of the building process and also assistance -just in case that you have questions and need some help getting this project done.


  • Loaded with fiberglass
  • Expensive
  • Heavy/light
  • Require shipping expenses
  • If horizontal -blow fiberglass particles towards user
  • Not customizable


  • Fiberglass FREE
  • Cheap
  • Light/heavy (as you design them)
  • Do not require shipping expenses
  • vertical -doesn't blow clean air towards user
  • Fully customizable


  • When building your own you can customize the equipment according to your needs. It's pretty much like making your own food and not relying on what's given to you at a restaurant. Growing mushrooms is not about high-tech equipment -they don't need fancy stuff, and in some cases what you'll build may even outperform the high-tech, that's why I'm always glad to see creative farmers out there
  • You'll need this to make quality mushroom spawn, fungus tissue transfer, prepare media, clone mushrooms and many more
  • It's fiberglass-FREE, so you won't get those particles all over your around you anymore.
  • It's easy to build, and very cheap. Most flow-hoods cost from $500 up to several thousands. Besides that the shipping cost would get a hole in your pocket especially if you want to purchase a big one. Instead with about $250 investment you could get the same results.
  • Most spawn companies out there have limited strain availability as spawn (ready to ship). If what they have doesn't match your location you might get low yields or no mushroom fruitbodies. By making your own your free to play around and test different strains and pick the best ones you like;



Flow-hood types

Filters & blower pick

Airflow calculus

Flow-hood efficiency


Fan-Filter unit buildup

Magic box buildup


Fan-Filter unit buildup

Magic box buildup


Structure and air current dynamics

Airflow rate calculus

Instructions on how to build it


Structure and air current dynamics

Airflow rate calculus

Instructions on how to build it


Check this awesome video sent by Allan one of my serious students who succeeded to build his own flowhood and prepare his own mushroom spawn and he’s about to set up his farm to grow mushrooms. A great feedback, thank you Allan! 

Allan, Barbados

“I just wanted to show you what we cooked up. Thanks for the course, it really helped a lot.

Yeah she took a lot of effort, very stoked with the outcome (and the 3m filters doing what they are supposed to).”

Byron, South Africa


If you have any questions here you’ll get some answers


Take a look on what the next class has to offer you


Make sure to check terms and conditions before you purchase this

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