ᐅ Internal insulation

We live in an older house with a beautiful brick facade. Since the walls are not insulated, which is noticeable not only on the heating oil bill, we want to insulate the exterior walls. Are interior insulation solutions straightforward to implement, and what should we be aware of?

Hello Herti,

Interior insulation is not without challenges; you must especially ensure that no warm air gets between the interior insulation and the exterior wall. Otherwise, the warm indoor air will condense at this transition area between insulation and wall, which over time leads to moisture problems.

However, there are some interior insulation systems designed to address this issue; if you search online, you will find a few practical systems.
For DIY projects, an interior insulation made of mineral wool insulation installed between wood or lightweight metal studs fixed to the exterior wall is suitable. Above this, a continuous vapor barrier must be installed without gaps, followed on the interior side by drywall or gypsum fiberboards, clay boards, or similar materials.

Interior insulation must be professionally installed to avoid major problems. I would recommend hiring a specialized company for this to minimize any risks.

We also had this done afterwards in my parents' house, and the oil bill was much lower the following winter. A stud wall was constructed with mineral wool insulation on the inside, followed by drywall.

People with DIY skills can install this kind of internal insulation themselves. Lightweight metal studs can be assembled quickly, and mineral wool insulation is available at any hardware store. Gypsum plasterboards can also be found there. It doesn’t get any easier than that.

It’s not that simple, and we experienced moisture issues. I couldn’t explain it, but mold even started to develop. We then had the stud wall removed and rebuilt. So far, everything has been fine.