How To Build a Grow Room in a Basement – Step By Step!

This is a guide to help you learn how to build a grow room in a basement, enabling you to grow any time of the year.

The grow room is the most important part of the cannabis growing process; it’s the place where the plant grows and develops. It should be a very well-ventilated area, with good airflow and humidity control. A grow room can be located anywhere as long as the conditions are right for the plant to grow sufficiently; this includes temperature, humidity, light, ventilation, etc.

A grow room can be located in a garage or basement; however, some growers prefer to build their own grow room, because they have more control over the environment, and they are more likely to achieve the results that they want.

This article will show you how to build a grow room in a basement; but first, we will discuss the different options available when choosing a location for your to grow room. One option is to build a grow room in your basement, this would be a good option if you don’t have access to a greenhouse or a heated indoor grow space. You can also build your grow room in a garage or a spare room in your house.

Read more about How Long Does It Take For Roots To Grow Out? 

How to Build a Grow Room in a Basement

If you want to build a grow room, it is important to start by collecting the materials you need. The materials include:

A grow room needs a foundation that is strong enough to hold the weight of the walls and roof. A solid concrete slab is recommended.  The size of your room should be big enough to hold all the equipment and the plants.

If you are going to use an existing room, make sure it has a good ventilation system, a temperature control system, and a lighting system. Make sure you can reach all the parts of the room easily.

Some other equipment you’ll need to get started are: sufficient lighting and electricity, and separate areas if you plan to grow year-round.

Steps To Build a Grow Room:

Step 1: Construct a structure, such as a wooden frame covered with chicken wire or other material.

Step 2: Cover the structure with layers of paper and insulation, such as polystyrene, polyurethane foam, fiberglass, or mineral wool.

Step 3: Fill the structure with growing medium, such as sphagnum peat moss, perlite, vermiculite, Rockwool, or coir.

Step 4: Place plants in the growing medium.

Step 5: Put on a light source, which should be adjustable to allow for growth cycles, that vary between 12 and 16 hours per day.

Step 6: Lightly water the plants, and place a small fan to circulate air. Monitor water levels. If necessary, add water using a drip irrigation system.

Step 7: Check the temperature of the grow room. It should be controlled at approximately 22 °C (72 °F). Place a thermometer inside the grow room to monitor the temperature.

Step 8: Check humidity levels. They should be maintained at 50% to 60%.

Step 9: Check ventilation levels, ensuring air is circulated through the grow room, and that there is no condensation.

Step 10: Once the plants are growing well, set up a watering system.

Step 11: Keep an eye out for pests and diseases.

Step 12: Once the plants have been growing for a few weeks, harvest them and store them in a freezer for future use. Remove the plants from the grow room when they are ready to be moved to another location or to be harvested.

grow room

Tips to Make Your Grow Room Work Best

Grow rooms will work best when they are well-designed and optimized. Here are some tips that can help you with this process:


When planning your grow room, consider the size of the plants and how many you plan to grow. You can start with a small grow room and expand it later. Either way, you’ll need to consider where you want to place your grow room in your house. This should take into account the size of your house and the amount of space you have available.


The most important element of a grow room is the light it receives. Plants grown in a dark room will not be as healthy or productive. Make sure that you provide enough light so that your plants do not struggle to grow. Grow lights should be placed in the middle of the room, at an angle of 45 degrees, so that the plants can receive the full spectrum of light they need. Grow lights are not a necessity, but they’re helpful (and expensive).


Your grow room must have the correct temperature for your plants. In colder months, you’ll need to use a heater. Keep in mind that you should not use heating systems that emit toxic fumes.


Another element of a growing room is humidity. The ideal level of humidity will vary depending on the plant. For instance, cannabis plants require high levels of humidity. On the other hand, plants like orchids can thrive with low levels of humidity. Make sure that you keep the humidity at a moderate level.


You need to have adequate air circulation in your grow room. This is essential for the health of your plants. Make sure that you have enough ventilation to keep your grow room cool. Also, make sure that you have enough ventilation to help circulate hot air from your heating system, in colder months.

Learn more about How To Control Temperature And Humidity In Grow Tent

Frequently Asked Questions

How Cold is Too Cold for a Grow Room?

65-75F is the ideal temperature; anything less than 60F during the day and your plants will struggle to thrive. Some plants require hotter temperatures, so always be sure to check depending on what you're growing.

How Do you Get Fresh Air in a Grow Room?

The easiest way is to open a window. Make sure that you can close it when the room gets too warm or too cold. If you have an exhaust fan, this is also helpful at keeping fresh air in the room - just be sure it's turned on!

How Often Should You Exchange the Air in Grow Room?

For a standard 6’ x 4’ x 3’ room, you should change the air every 1-2 weeks. The reason is that if you leave the room for more than 2 weeks, you will be pulling all the fresh air out of the room. If your grow room has an exhaust fan, make sure it is turned on so that it pulls air out of the room.

How Do I Make My Grow Room Warmer?

Make sure that there is enough ventilation and that your grow room does not get too cold. You can use an electric heater or a radiator to warm your room. You can also try using heat lamps, or LED lighting to help the temperature of the room.