How to Build a Grow Room on a Budget
Ready to set up a grow room? It doesn’t have to cost the earth.
For most people after a cheap indoor grow setup, there are three main steps involved:
- Choosing your lighting
- Picking a tent
- Controlling your climate
The easiest & cheapest thing to do is to get a grow tent kit.
- Easier - skip the sizing up (lights, tent & extraction are included)
- Spend less- it's cheaper buying a kit than it would be to buy everything on its own
- No mistakes - we've hand picked everything in these kits to give you great results
Our cheapest grow kits cost less than £70.
If a kit's not for you, you can still get a cheap indoor grow setup and buy everything individually:
1. Choose your Grow Tent (or Kit)
The size and shape of your grow tent needs to:
- Fit into your available space
- Suit the size and intensity of your grow lights
As a rule, here’s how much space you need for each grow light:
|250W light||0.75m x 0.75m||200cm|
|400W light||1m x 1m||200cm|
|600W light||1.2m x 1.2m||200cm|
|750W light||1.2m x 1.2m||200cm - 215cm|
|1000W light||1.5m x 1.5m||215cm - 240cm|
If using fluorescent propagation lights, you only need a small propagation tent, because the light intensity is so low.
When sizing up your tent, make there’s enough space for ducting at the top and sides of your tent.
|Money Saving Hint:|
Pick a tent that’s going to last. It may be more to buy, but if it lasts longer, it costs less overall.
2. Choosing your Grow Lights
There are lots of lights to choose from. For their main grow, most people use an HID light or LED light.
Most of the time you'll be using a CFL light for propagation, then switching to an HID lights for your main grow.
LED grow lights
LED grow lights are are cool and cheap to run. Lots of growers switch to them in summer.
Even when trying to save money, don't go for a cheap LED light. They don't emit a good enough spectrum or penetrate far enough into the canopy layer. It's worth spending extra on a decent LED light.
The ones we sell (GN Telos) emit at least 2.1μmol per W - that'll give some of our best HPS lights a run for their money.
Best LED: Telos LED
CFL (compact fluorescent lamps)
HID (High Intensity Discharge) lights
These emit mostly red and blue light from the 'PAR range' - the light plants need for growth.
The one you want is a dual spectrum HPS light - they emit blue and red light, for veg & flowering
Budget HID: BAY6 Lighting System (choice of reflectors)
Supplemental grow lights
These lights are used alongside your main HID lights to improve yield taste, aroma, appearance & quality.
- 315W CDM (Ceramic Discharge Metal Halide)
- 270W LEP (Light Emitting Plasma)
With the right reflector, in the right area, you can use 315W CDM as a standalone light.
Budget Supplemental: Maxibright CDM Lighting System
You've basically got two choices of ballast - magnetic or digital.
Magnetic ballasts: Are cheaper to buy and get the job done.
Digital ballasts: Cost less overall (cheaper to run, last longer, prolong lamp life)
Your light coverage is determined by your reflector (if using HID) lights. So the shape of your reflector needs to match the shape of the growing area.
The easiest way to get it right is to split your grow tent into sections, then position a reflector in the centre of each section.
|Money Saving Hint:|
If building a cheap indoor grow set up, consider running your grow lights at night . You'll spend less on electricity because night time tariffs are lower.
It’s also cooler at night, so fans or air con systems don’t have to work as hard during summer.
3. Set Up your Climate Control System
There are two ways to do it. You can exchange air or create a closed loop room. Most people looking for a cheap indoor grow set up will exchange air.
This is where you extract stale, hot, humid, CO2 depleted air and replace it with cooler, less humid, CO2 rich air. You also need to remove any odours before extracting air.
- Extractor fan
- Intake fan / intake vents
- Carbon filter
- Fan speed controller (optional)
The easiest thing to do is buy an extraction kit and expand on it if you need to.
It's tempting to opt for a cheap extractor fan or kit (AC), but you actually save more money overall using a higher end EC fan or kit. They cost so much less to run that your fan pays for itself and then some.
Budget Kit: Eco Extraction Kit
To work out how many cubic metres of air your fan needs to extract an hour:
Multiply your tent's L x W x H.
The answer is how much space is covered by your grow lights.
In a XL BAY6 Tent:
1.2m x 1.2m x 2m = 2.88m3
Multiply this by 60
That'll tell you how much air to extract every hour.
2.88m3 x 60 = 172.8m3
If you’re only extracting a small amount of air, you can get away with drawing air in through vents. Otherwise, pick an intake that draws in 20% less air.
|Money Saving Hint:|
To cut costs, swap your RVK fan for an EC fan To read more, hop over to EC vs. AC fans.
To Create a Closed Loop System:
For complete climate control, you’ll want a closed loop set up. Hardly any air enters, hardly any air leaves. Instead of exchanging air, you constantly treat the air with a climate control system.
Hardly any air enters, hardly any air leaves. Instead of exchanging air, you constantly treat the air with a climate control system.
The cheapest climate control system for you depends on how you pay the bills. If you're on a water meter, you're better off with an air-cooled unit. If you have a fixed rate for your water, a water cooled system could be the answer.
Best Air Cooled:
Don’t forget that you will need to add CO2 and dehumidify the air in a closed loop set up.
On a budget, you will probably want to grow in pots using media. Check out our artile on picking a growing system.