How to Insulate a Basement

Do you want to convert your basement into a garage, a DIY workshop, a laundry room or even a bedroom? But, it’s common for basements to be cooler and wetter. Being below ground, they are affected by leaks in most cases. In the same way, dampness by capillarity is also quite frequent. Whatever the origin, dampness causes problems on the foundations and structures and health problems for those who inhabit there. Don’t worry! You can fix it with insulation. This article will teach you some simple steps about how to insulate a basement.

Apart from the thermal performance, one of the indispensable benefits of basement insulation is the money saved from the energy costs. But, before you get started, there are a number of things to check.

Discover the checklist for successful basement insulation below!

Precautions to Take When Insulating a Basement

Suppose you plan to build a basement and make it a living room. In that case, it is advisable to call on a professional to carry out a soil study to determine its nature and ensure that a finished basement is possible.

If you plan to fit out an existing basement under renovation, it is essential to make sure that your home’s foundation is in good repair. Thus, check that there is no sign of moisture or structural problem and that the concrete is not cracked or crumbling. It is essential to correct the problem since it could greatly impact your safety and your health.

The goal of a basement remodeling project is to improve the place. Therefore, you must first correct the problem. If you start renovation anyway, be aware that it may not be helpful.

  • When you are sure about the good condition of your foundation, you can choose your insulation, which is essential for your basement to be healthy. Choose the right insulation solution for your underground basement. The key to implementing depends on the use you plan to make of the basement.
  • Suppose you want to create an unheated utility room (garage, laundry room, DIY workshop, etc.). In that case, the insulation installed on the basement ceiling will limit the thermal bridge between the heated house and the basement. You can attach glass wool insulation panels to the ceiling with an aluminum finish for a cleaner look.
  • If you want to create a heated living room (bedroom, games room, office, etc.), it is better to provide insulation for all the walls of the basement (walls, floor, floor) for maximum thermal comfort and acoustic. It ensures the continuity of the insulation between the walls.

Extending your ventilation system to rooms in the basement is all the more important if you are setting up a living room in the basement. Ventilation is essential to evacuate the exhaust gases that would enter the room and thus affect the health of the occupants.

Therefore, it is essential to provide, for example, a window for the living rooms in your basement. There must be at least one opening to the open air. In addition, this will naturally ventilate your room.

Once you’ve checked the feasibility of your basement, you can start with the insulation process, and for that, you need the following things.

What You’ll Need

Expanded polystyrene panels

Hammer drill

How to Insulate a Basement

To install insulation in your basement, you can do work inside or outside. Most of the time, it is easier to proceed indoors since the procedure is less expensive. Indeed, the foundation walls being partly in the ground require excavation during insulation from the outside. It is also less disturbing to insulate the walls inside, and it is, above all, more effective in increasing comfort and reducing heat loss.

Expanded polystyrene panels are considered effective materials when it comes to insulating foundations over the entire surface of the walls. Moreover, there are insulators on the market that are simple to install and applied directly to the concrete wall.

The expanded polystyrene insulation panels are available in different formats and thicknesses. They facilitate the insulation installation since these rigid panels may also have wood furring integrated at 16 inches. So you don’t have to calculate and cut wooden slats; everything is already in place! Plus, you don’t have to worry about which layers to adhere to during installation because they are simple and little in number.

To insulate the interior foundation walls of your basement, the layers to be respected are as follows:

  • the concrete wall,
  • the insulation board with the integrated wood furring,
  • the gypsum board,
  • And finally, the wall covering (tapestry, painting, etc.).

To fix the insulation, all you have to do is drill three holes through each fillet of wood into the concrete and screw in with screws or concrete nails. You’ll save time, and your new basement will be ready faster! You won’t even need to apply glue.


An effective practice is to place plaster (drywall) on the interior walls of the basement. It works very well to fill the gap between the plate and the wall with polystyrene panels to reinforce the thermal insulation. It is ESSENTIAL to place a polyethylene sheet behind the plasterboard. In this way, it is possible to prevent the condensation of water vapor inside the insulating chamber.

Expanded Polystyrene, a “Green” Choice

In addition to being effective insulating materials, expanded polystyrene panels are made of 100% recyclable material. They are composed of 98% air and 2% material, so they are not toxic. Also called Styrofoam, this insulation can make your home healthier because it is resistant to water and moisture, which will prevent mold from growing.

Some Important Tips

  • The method discussed above is the least expensive but is only advisable in basements with visible signs of water infiltration. You should not use this method if you have a history of water, even in small amounts.
  • It is also common for basements to have low ceilings. Keep this factor in mind because insulation from the ceiling will lower the height even more, and you may not want to have an awkward space for yourself.
  • Finally, it is also possible that by insulating the basement ceiling and the walls, the space is always cooler than the rest of the construction. If that’s your intention, go ahead, but don’t forget to keep that in mind.

Our Final Thoughts

Now you know how to insulate a basement with insulating panels fitted with integrated wood furring. It makes the work easier and reduces execution time. You will therefore be able to benefit more quickly from the comfort of your new healthy space in addition to making interesting savings on your electricity bill!