Exterior walls and attics must be insulated, as we all know. But do interior walls need insulation? Interior wall insulation is the process of insulating the inside face of external walls. Many people believe that insulating interior walls is unnecessary, yet they can aid energy efficiency and soundproofing.
Moreover, not only it can help smoothen heat transfer between rooms, but it also helps with moisture control inside the room.
Yes, of course insulating the interior walls will bring some benefits eventually. But the real question is, do you need insulation in interior walls?
Well, to help you decide, let’s see the pros and cons of insulating interior walls.
Do Interior Walls Need Insulation: Pros and Cons
- Pros: Energy Saving
Insulation in the external walls and roof is well established to save energy by lowering reliance on conventional heating or cooling. However, insulating interior walls can indeed give a significant efficiency to energy savings. With interior wall insulation, you can create climatic zones within a room for more efficient cooling and heating inside your house.

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Internal wall insulation will prevent heat or cool air from transferring into or out of the occupied room. You just need to close the unoccupied room’s door. This is significantly more efficient than trying to cool or heat the entire house artificially. It is an excellent approach to better energy efficiency.
- Pros: Sound Proofing
If you require a more tranquil living environment, then interior wall insulation is needed. Sound transfer from room to room is reduced by insulating inner walls. It can act as a sound barrier, containing inside noises while muzzling undesirable outside noise better than just insulating external walls.
- Cons: Add Cost
Insulation in interior walls indeed needs an extra cost. The additional cost varies depending on the material you use for insulating interior walls. Generally, the interior wall insulation will cost in the range of $40 and $50 per m2, but it might cost more than $100 per m2 when a wall is already installed, including materials and installation.
- Cons: Minimize your room size
Another disadvantage in insulating the interior wall is it could take up more space in your room. The material used will eventually thicken your walls. Insulation boards can add up to 10cm to the thickness of your wall.
Best Insulation for Interior Walls
What is the most appropriate insulation for the interior wall will depend on the application, so you need to know better what you require.
If you need insulation that doesn’t take up too much space, use a rigid foam board or consider mineral wool, which is effective yet less bulky. However, be aware that this kind of insulation material might stretch your budget as it is relatively more expensive.
If you want more breathable insulation, you can choose natural materials such as wood fiber, sheep’s wool, or mineral wool. These options are also considered more eco-friendly and fire retardant, releasing fewer harmful substances.
Read also: What Is R-13 Insulation Used For?
When considering insulation for interior walls, it’s crucial to understand the specific needs of your space and the benefits each type of insulation can offer. Whether it’s for energy efficiency, soundproofing, or moisture control, the right insulation can make a significant difference in the comfort and functionality of your home.
So, the answer to ‘do interior walls need insulation’ is dependent on your requirements, budgetary constraints, and local building codes. To ensure compliance, it’s important to check these building codes when insulating existing interior walls.