Grow Room Insulation: The 5 Best Ways to Insulate and Heat Your Grow Room

Grow Room Insulation

When it comes to growing marijuana, growers need to be aware of the fact that one of the things that is very important to the process of growing weed is heat. While air and water are important aspects, heat also has a major role to play. By heat we do not mean hot temperatures, but temperatures that are warm enough for the proper survival of a plant. Over the course of this article, we shall be taking a detailed look at all the aspects of grow room insulation. How to insulate your grow room and how to heat it as well.

We shall also be taking a look at some of the best grow room heaters, as well as techniques to ensure that the room remains warm. However, before all that, we shall first look at why heat is important for the growth of marijuana plant, followed by understanding what insulation means. We then look at the methods of insulation and heating up the room, and then a quick look at the best grow room heaters in 2020 before we conclude!

Why is Heat Important for Growing Marijuana?

Before anything else, it is critical to understand that by heat, we mean warmth. Warm environments are good for the growth of plants – but it should not be too hot else it might get counterproductive! Warm environments are good for the plants at various stages, but most importantly during the germination phase. When the plant is still in the seed phase and you start off with the process of germination by soaking the seeds in a wet towel, you need to ensure that the temperature around the seed is warm – this is the ideal condition for the seed to germinate and then grow into a seedling. This is also why lights hang close to the seed during the process of germination and eventually start moving away as it grows.

Warm environments ensure a better chance for your seed germinating. In addition to that, warmth has a number of other benefits, which include the plant getting a better environment to grow in because heat ensures that all the chemical compounds are released in time which are important for processes such as photosynthesis as well as for the generation of chlorophyll and other important enzymes and pigments which the plant needs for a healthy growth. In addition to all this, when the plant begins to mature, the growth of the shoot also improves when your plant is growing in a warm and insulated area.

In addition to all this, growers who are growing plants in regions which are very cold need warmth and additional sources of heating just to ensure that the plants are not affected by the extreme cold temperatures that surround the grow room! Over the course of this article we shall be looking at both these aspects in detail and talking about grow room insulation at length.

Understanding Insulation

Insulation is not the actual act of heating the room, but the means by which you keep the warmth preserved. Insulation is important because keeping the heating source on at all times would mean that plants would suffer from the excess heat. However, growing plants in a warm setup makes sure that while the temperatures are not getting too hot, they are ideal for growth. An insulated setup promotes growth of the shoot and the production of compounds, etc. as well as adds to the humidity which is very important for any grow room! Grow room insulation is an important aspect of growing plants and sometimes growers tend to overlook this. Let us take a quick look at the five best ways to insulate your grow room:

5 Best Ways to Insulate Your Grow Room

As you have read and observed by now, insulation is very important for growing plants in a grow room. As important as it is to heat a room, it is also important to make sure that the room has been designed in a way that it actually retains the heat. There is no point in heating the room if it has poor retention as this will only be a temporary relief and you will be spending a high cost on heating your room as well! Here are 5 best ways to insulate your grow room, doing which will make sure that the heat that you provide to the room will be retained inside it!

1. Regular Insulation Process

Get hold of a good contractor who would do the job for you! A good professional would know exactly what kind of material would be needed to insulate your room. They will examine the existing materials used to construct the grow room and will then recommend you with the best options that you have when it comes to insulating the room. These are professionals who would scrape through existing layers and then make sure your room remains well protected against the winters as well as warm at all times.

2. Seal Your Grow Room

Sealing the grow room is one of the best ways in which you can make sure that the insulation improves. The more the space for air to go out, the lesser insulated your room is. Make it as airtight as possible – this can be done by making sure that there are no gaps between doors and the floor and that the windows shut properly. Make sure that there is no surface which goes unchecked. Use thick sealing material to make sure that your room remains insulated.

3. Thick Walls

The thicker your walls are, the better the chances of your room being well insulated are. Rooms which have thin walls are the worst for growing plants as thin walls don’t really retain heat. Same is the case with wooden rooms, sheds and attics which have very thin walls or are made of non-standard materials which are not suitable for a good insulation. Hence, growers are advised to grow marijuana in rooms which have a thick wall.

4. Grow in a Basement

If you are setting up a grow room, it is best advised to set it up in a basement from the point of view of insulation. This is because earth is the best insulator and can retain a lot of heat, providing you an almost-natural insulation! However, you might have other problems if you choose to grow in a basement such as the lack of light and ventilation, but when it comes to retaining warmth, this is one of the best grow room insulation tricks that many growers use!

5. Use Thick Curtains

Last but not the least, one of the biggest problems that growers face when it comes to insulation is that of glass. Glass windows tend to cool up pretty quickly and don’t retain heat that well. Using thick curtains is one of the best ways to make sure that you are countering this effect. Now that we are talking about windows, also make sure that your windows are well insulated and that there are no cracks or gaps which are allowing the heat to escape.

Recommended: Best Grow Tents for Growing Marijuana Indoors

How to Heat Your Grow Room?

The best way in which you can heat your grow room is by buying a heater and setting it up. There are a number of benefits of this – especially if you are living in a cold place. There are some other options as well, which include using high heat emitting light sources or moving light sources closer to plants, but we believe those to be counterproductive and using a small space heater is just the perfect and the best solution. Here are the best grow room heaters that you can use to ensure your plants are getting sufficient heat:

Best Grow Room Heaters in 2020

1. Best Portable Heater for Grow Room: Vornado MVH Vortex Heater with 3 Heat Settings

Vornado MVH Vortex Heater with 3 Heat Settings, Adjustable Thermostat, Tip-Over Protection, Auto Safety Shut-Off System, Black
  • HEAT DIFFERENTLY - Gently heat all in the air in a small to medium-sized room through vortex air circulation without using intense heat, similar to how a forced...
  • HEAT SAFELY - Advanced safety features include a cool-touch exterior, tip-over protection, and automatic safety shut-off system for worry-free use.

When looking for the best grow room heaters, make sure you check out this one from Vornado! This one costs just under $60 (the next one is half of this!) and performs quite well. The heater is very uniquely shaped and provides the growers with a good heating experience. It comes with a cool-touch exterior meaning it won’t burn you if you touch it while the heating process is on, and you can easily move it around. There are three heat settings ranging from 750W to 1500W allowing the growers to adjust to the temperatures that they deem suitable.

Talking about adjusting the temperatures, there’s a built-in thermostat as well, which makes sure that the growers get a comfortable heating experience. Another advantage for growers buying this from the US is that this is compliant to all the voltage requirements of the US and will be a perfect fit for your grow room. It is designed in a way that it can circulate heat all over your grow room. This grow room heater also comes with built-in safety features that make sure there is no operating risk as well!


  • Large number of safety measures
  • Portable, easy to move around
  • Circulates warm air in entire room
  • Comes with thermostat
  • Good design


  • Some users find it a little weak for big rooms

Check Price & Reviews on Amazon

2. Best Cheap Heater for Grow Room: Lasko Ceramic Portable Space Heater

Lasko Ceramic Portable Space Heater with Adjustable Thermostat - Features Widespread Oscillation to Distribute Warm Air, Silver 5409
  • Ideal for tabletop or floor use with easy to use top-mounted controls
  • Adjustable thermostat

For those growers who are looking for a heater for their grow room but do not want to spend a lot of money on buying one, this is a great option for you. This is also a good grow tent heater for those growers who grow their marijuana in a big grow tent. This is a portable heater from Lasco and it costs just $30. It has a great design, and also comes with important features such as an adjustable thermostat which allows you to ensure your room does not overheat. The heater is easy to pick up, carry and move around the room as it comes with a handle on top. This is indeed one of the best grow room heaters.

There are three settings – the first being a fan-only mode, the second and the third being ‘low heat’ and ‘high heat’ modes. You don’t need to ‘set up’ this heater. Simply plug it and start using it – making it a good option for beginners. Another great feature about this heater is that it is very silent in terms of operation. There are some which make quite the noise! This one, however, doesn’t really make the annoying sound!


  • Does not make much noise
  • Thermostat allows you to set just the right temperature for your needs
  • Easy to move around
  • Simple to use
  • Not expensive


  • Some users have reported that the lifespan isn’t long enough

Check Price & Reviews on Amazon

Recommended: Best Grow Tent Ventilation Kits

Frequently Asked Questions About Grow Room Heaters and Grow Room Insulation

1. What is the Ideal Temperature to Grow Plants?

The ideal temperature depends from plant to plant. However when you talk about the marijuana plant, it grows well when the temperatures are around 68-77F (20-25C). Growers who grow their weed in these temperatures have seen the maximum yields and flowers. Growers who go too hot or too cold tend to suffer as their plants might get damaged. However, this is not a hard and fast rule and you can go to 15C/32C and that won’t be counterproductive either. However, this is the best possible range for growing weed.

2. Is Insulation Expensive?

Yes, if you get it done professionally, insulation can be quite an expensive affair. A professional setup would see you hiring a contractor who would charge you for the material, the labour, and for his services. All of this would require tearing down certain portions of your existing interiors and installing additional layers so that they can retain heat. This is a complex and tedious process which can take quite some time to get done with. However, if you decide to do it yourself, you can save quite a bit of money but you need to know exactly what you are doing.

3. Is Grow Room Insulation Compulsory?

No it is not compulsory to insulate your grow room in order to grow marijuana plants. However, it is best advised to do it because insulating your grow room will protect your plants against cold waves. The shoots grow better when the grow room is insulated and the plants also find these warm climates comforting.

4. What Happens if you Overheat the Grow Room?

Overheating the grow room might lead to a number of problems – first off, the source of heat might get too hot (light or heater) and might get damaged. In the worst case scenario, the heat source might even catch fire! In addition to that, overheating the grow room might mean that your plants face the brunt of it and end up getting burnt out. The edges of the leaves are the first to feel this and they start turning dark and curl. This also impacts the chemical composition of the plants negatively.

5. How to Cool the Grow Room if it gets too hot?

Using an air conditioner is the best way to ensure that your grow room does not get too hot and that your plants are all safe from any possible heat-related damage. Insulation and heating are good but only in certain situations and for a certain degree of heat.

RecommendedBest Multi-Chamber Grow Tents for Growing Marijuana Indoors


We hope that this article on grow room insulation and grow room heaters helped you understand the concepts of heating and insulation in a better manner and helped you gain a better insight into how you can ensure that your grow room remains insulated. There are a number of things that need to be taken care of and we hope that you will use this knowledge to ensure that your grow room is well protected against cold weather. If there are any other insulation-related questions that you might have, or if there is something that we have missed in our coverage, inform us in the comments below or drop us an e-mail!

Happy Growing! 🙂



Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.