In this new, exclusive series from Advanced Nutrients we show you to build your own indoor hydroponic garden so you can start enjoying the benefits of growing!
How To Build Your Own Grow Room Series:
Part 1 — Choosing your space & planning
Part 2 — Calculating lighting and insulation needs
Part 3 — Dialing in your temperature & humidity
Part 4 – Accurately calculating heat, plus safety & sanitation tips (you are here!)
In part one we covered how to choose the perfect spot for your grow room, including many factors that you needed to keep in mind to set you up for success.
In part two, we went over calculating the lighting you need and insulating your grow room.
Part three covered the ideal environmental conditions you’re looking for and the importance of proper ventilation in your grow room and the two major ways growers achieve this.
Today, we’re going to going to get into the nitty gritty of how to calculate how much heat will be in your grow room using some important math equations.
Don’t worry, you can easily follow along!
Why It’s Critical To Fight Heat In Your Grow Room
By far, one of the most common problems in grow rooms everywhere is the temperature can easily get too high.
This is (mostly) because of the high-intensity lighting and other industrial equipment that is commonly used with indoor hydroponics grow rooms. These tools put out heat. Lots of it!
This can lead to all kinds of problems that can affect your high-value plants negatively.
The bottom line is that you have to be extra careful to fight excess heat in your grow room.
And the best way to do that is to plan ahead. To do that, we’re going to walk-through the simple math that allows you to figure out how much heat you’ll be generating in your particular grow room.
This will allow you to know if you cooling plan is going to work or if you need to make some changes like increase the amount of fans and/or A/C units.
How To Accurately Calculate How Much Heat Will Be In Your Grow Room …
Expert grower Eljay breaks this down for us to make it super simple …
What’s important to understand is there are several other items in the grow room that put off heat as well such as Ballasts, air pumps, CO2 Burners, dehumidifiers and the room itself. And you can also add most anything else that runs off gas or electricity. However the lights are always the biggest culprits.
It is always a good idea to be conservative with your air cooling measurement and allow for a little extra air conditioning to stand up to warm days and auxiliary equipment in the grow room.
Let’s look at other devices that cause heat in the grow room. At this point we have a lot to consider. Doing this heat calculation is basically six steps:
- Natural Room Heat
- Light Heat
- Air Cooling Reduction
- CO2 burner
Let’s go through each one, step-by-step …
#1: Natural Room Heat
Suggesting Cooling BTU’s Before Adding Equipment
Room Dimensions (Square Feet)
Recommended A/C BTU
|5’ x 5’ (25 sq. ft.)||2,500|
|5’ x 10’ (50 sq. ft.)||3,100|
|10’ x 10’ (100 sq. ft.)||4,200|
|10’ x 15’ (150 sq. ft.)||5,300|
|10’ x 20’ (200 sq. ft.)||6,500|
|10’ x 25’ (250 sq. ft.)||7,500|
|15’ x 20’ (300 sq. ft.)||8,700|
|15’ x 25’ (375 sq. ft.)||10,400|
|20’ x 20’ (400 sq. ft.)||11,000|
|20’ x 25’ (500 sq. ft.)||13,100|
|20’ x 30’ (600 sq. ft.)||15,400|
|30’ x 30’ (900 sq. ft.)||22,000|
Now we add our natural room heat from the chart above. Pick the one closest to your sq. footage, mine will be the “100 sq. ft. 4200 BTU”
6 “1000 watt HPS bulb lights” x 4000 BTU “Bulb Heat” = 24,000 BTU
#3: Air Cooling Lights Reduction
Subtract the 40% Heat Reduction for air cooling the lights, brings it down to = 14,400 BTU “24,000 BTU – 40% = 14,400 remaining BTU”
14,400 BTU “remaining light heat” and add the 4,200 BTU “Natural Room Heat” = 16,600 BTU
If we used ballasts we would be looking at an additional 2500 BTU per Digital ballast and 3500 BTU per Magnetic Ballast. We would be adding these to give us a good calculation.
Dehumidifiers commonly add about the same heat as the low side of HPS bulbs at around 3.5 BTU per watt. The dehumidifier I am using is about 600 watts. So that would be 2,100 BTU.
600 “watts” x 3.5 “BTU” = 2,100 BTU
Then we would add that to our existing subtotal and get:
16,600 plus 2,100 = 18,700 BTU
#6: CO2 Burner
In the example video above, Eljay uses a Hydro Innovations Hydrogen Pro CO2 Burner. They have a great calculator on their website that will tell you how long your burner should run. His burner should run approx 5 minutes an hour, and run at 1000 BTU per 5 minutes.
Now we add this 1000 BTU to our existing subtotal of 18,700 BTU, and we end up with a total: 19,700 BTU
This 19,700 BTU is the whole load against our 22,000 BTU of cooling. Meaning we have 11% over what I need and should run great. But you’ll find out when you test it!
So just to recap. We add our components one at a time:
|Natural Room Heat||4,200|
|Air Cooling Reduction||Subtract 40%, in this case 9,600, leaving 14,400|
|Ballasts||None in Room|
Cooling installed: 22,000 BTU
And there you have it!
That’s the simplest way to calculate all the heat that your grow room will be generating.
Remember, one of the primary benefits of controlling your environment like this is how it helps to fight pests.
But there are also many steps you can take when you’re in the planning stage of your grow room that you should think about to ensure that you’re doing your best to keep things clean and sanitary.
Here’s our top five list …
5 Sanitation and Safety Tips For Your Grow Room
By taking some simple steps to keep your grow room clean, you’ll reduce the risk of getting pests and disease which will help you get and maintain higher yields.
What’s more: a messy grow room is an accident waiting to happen. Remember the saying, “A place for everything, and everything in its place”.
Lastly, you’re investing a lot of time and money into your grow room and the equipment inside–take care of it!
With that in mind, here are some sanitation and safety tips:
1. Clean up dead plant matter! When you’re inspecting your plants, look for fallen leaves on the ground, inside plant containers or within your hydroponic system.
By removing fallen leaves you’re also removing a breeding ground for pests and disease. The same holds true for soil or root matter. Don’t store soil or root masses in or around your grow room because dead plant matter is extremely attractive to a variety of pests but especially fungus. Many gardeners with root rot problems don’t ever associate their problem with dirty grow rooms.
2. Clean your intake filter! You definitely want an intake filter because they help keep unwanted dirt, dust and bugs from ever entering your grow room.
Clean the filter once a month to restore maximum air flow and inspect for bugs. Early detection on an intake filter can give a gardener a jumpstart on treatment programs.
3. Clean bulbs and glass! Remove grow light bulbs and glass from reflectors and clean them about once a month. Even with an intake filter, bulbs and reflectors develop a thin layer of dust capable of compromising their performance in your hydroponics grow room.
Cleaning the bulbs and glass in your grow room can help you maintain the maximum light output at all times. It is a good rule of thumb to also wipe down any reflective material on your walls or ceiling.
4. Clean up spills, excess water or plant runoff. Many times indoor gardening can leave you with a wet floor. Invest in a wet/dry vacuum to suck up any spillage or run off. Leaving moisture on the floor raises humidity levels and increases your risk of mold or rot.
5. Clean and maintain your growing equipment. Every two months it is a good time to inspect and clean all the hardware in your grow room. An air compressor jet of air blown onto and into an HID ballast can clean out dirt and dust, prolonging its life and efficiency. (If you don’t have an air compressor, the compressed air sold to clean computers will work as well.)
Air conditioners, dehumidifiers, heaters, CO2 emitters, atmospheric controllers, light timers and fans should all be inspected and cleaned on a regular basis.
Like most things in your garden, it helps to take notes on a calendar to remember when and what you did.
Wrapping It All Up …
At this point, we’ve been through the entire series on how to build your own grow room for beginners. Using the information in our multi-part guide you should have no problem getting your first grow room setup.
After that, you’ll start “learning by doing” and you’ll develop your own tips, techniques and strategies to achieve all the goals of proper hydroponics growing.
We can’t wait to see what you do with this information!
Until next time, please share this article with your friends or anyone you think it can help. Post it to social networks too. Tag your friends. And if you use the information in any of these guides please tag us on social media with the hashtag #AdvancedNutrients.