In this new, exclusive series from Advanced Nutrients we’re going to 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 (you are here!)
Part 3 — Organizing your grow room and calculating environmental needs
Part 4 — Accurately calculating heat, plus safety & sanitation tips
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.
Plus, we showed you how to diagram out exactly how much space you need depending on how many plants you want to grow. Check it out here first, then let’s get started today with using those diagrams to calculate our lighting & insulation needs!
Why Is Insulation So Important For Your Grow Room?
Insulating your grow room is key and the main reason why is because you want complete control over your environment.
That means you don’t want any air leaking out, or coming in, unless you are controlling it.
What’s more: you want to be able to precisely control how much heat, humidity and other environmental factors are present in the room.
To do all of this, you’ll need to properly insulate your grow room.
Best Practices: How To Insulate Your Grow Room 101
In the video below, expert grower Eljay shows you how to seal up your room and hang panda film along with what tools you will need to complete this job.

Step #1: Seal Everything:
Now it is time to seal everything possible.
We do this with tape and dry wall mud, caulking, weather seal and foam gap sealer.
We not only seal our vents but also all creases or leaks in the room. We don’t want to allow too many air holes or gaps under the Panda Film we are about to roll out.
We are trying to tightly air seal this room after all.
Step #2: Panda Film.
Panda Film is a waterproof, light reflective, hard wearing film for lining the walls and floors of greenhouses and grow rooms.
Once we have sealed the room it’s time to hang our panda film. Panda film is not only going to further air seal the room – trapping the air inside to store C02 and smells, but will also provide a 90% reflective material for light bounce to further light our plants.
IMPORTANT TIP: If you have drywall underneath the Panda Film you are rolling out, then make sure to mark your studs on the floor with a sharpie pen. Once the Panda Film is up you won’t be able to use stud finders with any accuracy. By marking the ground, it will make it easier to mount fans and other wall mounted devices later.
Once you have sealed the room and hung panda film, you will now have a relatively controlled environment.
How To Calculate Your Lighting Needs
In the video below, Eljay explains the importance of how to calculate your lighting needs and how to do it:

Once we know our canopy area (like we figured out in part 1 of this series) in the room we can calculate our lighting needs.
A great way of calculating how much light you need is “wattage per foot”. The goal is to achieve a desired wattage per foot across your canopy. Target for this is 50 to 75 W per foot.
The important thing to remember about these target numbers is that you want to fall somewhere is the center of this range. Going to 75 watts a ft. might cause light burn on some flavors of plants, and you may need to lift or dim the lights.
The first thing we need to do is figure out the square footage of your growing area. Your growing area is the area designated for plant growth. Most grow rooms will have walkways and utility areas. These areas don’t count when it comes to calculating lighting. We’re trying to light the plants after all, and not the walkways.
To get the square footage of your canopy, we start by multiplying the length times the width of this area. In this example we will be using a 10 x 13 room with an 8 x 10 canopy. Remember that the canopy area is all that we care about for this exercise. We will then multiply the length of 10 feet times the width of 8 feet to end up with 80 sq ft. This is the square footage of the canopy area in this room.
Now if you want say 65W per square foot, we would then multiply 80 feet times 65 Watts to and up with the number 5200. This is the amount of total wattage in lighting that it would take to meet a target of 65 W per foot.
Here’s the fun part it’s completely at your discretion how you set up your 5200 Watts. You could do five 1000 watt lights equaling 5000 W, or you could do 9 x 600 W lights equaling 5400 Watts and both would be acceptable. We just want to end up close to our target number.
Once we know how much light we are going to need it will give us an idea as to the heat that’s going be generated, how big of a fan we’re going to need, and how complex of a ventilation system we’re going to need. (All these factors will vary according to the type and size of grow room that you are constructing and are somewhat beyond the scope of this article, but it’s important to note these factors).
Remember: Safety First When Working With Electricity!
When it comes to electricity, you want to be very safe because you could easily kill or harm yourself or even if there is no problem immediately–it could lead to an electrical fire in the future.
Here are some things to think about …
If you are doing any wiring, you will need to meet local safety regulations. Don’t skimp on these just because you want to save time or money. They’re for your safety!
Make sure that the amount of power used is adjusted to a range your connection can support. In other words, you don’t want to overload your electrical system running all your lights.
Don’t use a lot of shorter cables connected to each other to form one long line. Instead, you want to use one long direct cable. This minimizes the risk of electrical problems and is much safer.
If you’re doing any electrical work, then you should strongly consider hiring an electrician to help you to make sure everything is done safely and correctly.
Ideally, your grow room should make it safe to have both water and electricity present without any risks. Because they’re both necessary for the things your plants need (water and light). Again, this goes back to choosing the proper space in part one of this series — but if you can set it up in a way that both are nearby, it will be a lot easier for you.
Congratulations! Now You’re Ready To Control Your Environment …
In the next installment of this series we will cover:
- How to calculate how much heat you’re going to be producing
- Other environmental factors absolutely VITAL for happy crops!
- What you need to know about air quality and ventilation, fans, A/C and more!
Until next time, please share this article with your friends or anyone you think it can help. Post it to social networks too. And good luck with figuring out your lighting needs!