Should You Add Insulation Behind a Medicine Cabinet?

Should You Add Insulation Behind a Medicine Cabinet? (Yes, If…..)

Medicine cabinets provide a conducive storage environment for your medications.

Some of them are equipped with temperature regulation mechanisms to keep the contents at the right temperature at all times.

But because some homeowners prefer to install them in such musty environments as bathrooms and other places where temperature fluctuations can be an issue, you might wonder whether it would be a great idea to insulate them.

So, Should You Add Insulation Behind A Medicine Cabinet?

Yes, but it depends. If the conditions in the room aren’t extreme enough, you probably shouldn’t worry much. If you think the conditions are cool, you should shelf your insulation ideas as well. Actually cool is highly desirable in medicine cabinets.

Some manufacturers even make products that are purposely designed to maintain a cool environment for medications, and they are very expensive. These products help keep your medicines and cosmetics unspoiled for longer than the uncooled alternatives.

However, if you feel the wall and room environment is too musty and cold and this could pose a threat to your medications, you can go ahead with your insulation plans.

You May Add Insulation In These Scenarios:

1. It Is Exposed to Erratic Temperatures

If your cabinet is installed in a bathroom or any other room whose walls directly expose it to adverse temperatures and moisture, you should definitely add insulation.

Closed-cell foam insulation is the perfect option (more on this later)

2. It Is Outside Rather Than Recessed

Whether or not insulation would be viable will depend on the kind of wall and even the type of cabinet.

First off, you should be aware of the two main types of medicine cabinets (according to the style of mounting):

  • recessed
  • surface cabinets.

Surface-mount cabinets are installed to jut into your room i.e. they extend out, beyond, or over the wall line.

On another hand, recessed cabinets are installed to appear like they were built into the wall – a big part of these cabinets is inside the wall. To install them this way, you will need to do extensive planning to avoid walls with plumbing or outside walls.

If the cabinet is recessed, there is absolutely no point in adding insulation because it is partially installed in the wall.

This style of installation ensures that the wall protects it from moisture and cold air emanating from behind.

In fact, individuals planning to install their medicine cabinets in their bathrooms are often advised to install recessed cabinets (not surface) for that particular reason.

Even if you were to insulate it, you’d still have a hard time accessing the rear end of the unit because it would be buried into the wall.


It isn’t entirely impossible to add an insulator to this kind of unit; neither is it completely discouraged.

However, the labor and resources involved in the whole process normally aren’t worth it.

Still, if you can make this decision beforehand (like, adding an insulation material before you install the cabinet), then that would be perfectly okay.

Related: Should You Add Insulation Around a Circuit Breaker Box?

3. The Type of Wall – Exterior vs. Interior

We all know that an average homeowner’s choice of a medicine cabinet often depends on their type of wall (exterior vs. interior wall).

For example, it is strongly recommended that you don’t install a recessed cabinet on exterior walls, especially the 2×4 walls found on old homes.

It is very hard to get sufficient insulation – if any – at the rear of the cabinet to prevent the backside from being too cool compared to the remainder of the walls on your bathroom space.

Cooler walls translate to more condensation.

The moist air circulating through the bathroom will end up on the cabinet, condense on the cool surface, and create ideal conditions for mold growth.

This picture is a good example of this condition.

In such a case the right thing to do would be to relocate or install your cabinet on one of your interior walls.

Is Your Wall Already Insulated?

The second thing to consider is the insulation state of your home – are your walls insulated?

If yes, what kind of insulation material was used?

What is the R-value of the material?

You may stumble upon the insulation material as you dig in the wall to install your cabinet.

If you know everything about your home and you know it is insulated, there’s no point in trying to add another layer of insulation in your cabinet.

If You Are Thinking Open Cell Foam, Then Yes

There aren’t many insulators out there perfect for a cabinet like open-cell foam.

Ask any expert and the first material they’ll suggest is an open-cell foam kit.


There are 3 reasons for that:

1. Applied Pressure

Because closed-cell foams are denser, meaning they can apply a lot of pressure in tightly enclosed areas like between your cabinet and the wall and cabinet.

Such immense pressure could easily buckle the panels. The open-cell foam alternative is a bit more forgiving in that aspect.

2. Air Boundary

Open cell foam insulator will form an air boundary as perfectly as your average closed-cell foam except that the former comes with a thermal advantage as a result of its density.

3. Expansion

Open-cell foam material expands more than its closed-cell counterparts, so you will be free to complete the job with few holes drilled into the cabinets.

Six Precautions To Take If You Proceed to Insulate Your Medicine Cabinets

Some insulation materials are foamy chemicals, while others are made of fibers.

If you don’t take the necessary cautions, you could irritate your skin or eyes or get it wrong.

Also, prolonged exposure to such insulators as fiberglass can inflame your skin. Take these cautions:

1. Let a Professional Contractor Do It

Since insulation jobs can be tricky, you’d rather hire a qualified professional to do it than attempt it all by yourself. Hire a person with experience in cabinet insulation.

The best thing about insulation professionals is that they have worked on medicine cabinets like yours, and they will devote their time and energy to the job at hand.

Additionally, insulation contractors know which situations make your medicine cabinet competent for insulation and which don’t.

2. If You Choose The DIY Route, Wear Appropriate Clothing

Let’s say you have deep DIY skills enough to do the job all by yourself – no problem with that. However, remember to wear the right gear.

Under the gear, wear long-sleeved and long-legged clothes that can offer protection from eye and skin irritation.

If fiberglass or any other irritating insulation material lands on your skin, avoid rubbing or scratching your skin. Instead, get some cold clean water and wash your skin.

You can also choose to wear safety goggles for extra eye protection.

3. No Drinking or Eating

Avoid eating anything or taking any drinks during the installation process.

When insulating your medicine cabinets, you are likely to be exposed to debris and pathogens that can even get in your nose or stomach and cause an upset.

4. Keep Insulation Sparse

If you concentrate too much insulation material in one place, you are going to fill every tiny hole available and make the surface a pool thermal conductor.

For that reason, you should keep your insulation layer about 1” deep.

Also, avoid over-applying your insulation foam since it can end up stressing some parts of the cabinet.

5. Leave No Gaps

It just doesn’t make sense to leave gaps anywhere during insulator application.

Avoid gaps at all costs. By leaving about 5 percent of the area un-insulated, you stand to lose about 30 percent of the prospective benefits.

Check your cabinet and identify the presence of holes if any.

Additionally, avoid using loose or grainy insulation materials as they can leave spaces that could easily trap air in the compartment, thereby making the entire project ineffective.

6. Check R-Value

This is important – find out the R-value (and even the thermal resistance) of your preferred insulation material.

You should be aware that an insulation material with a high R-value is likely to be more effective at the job behind and under and behind the cabinet.

Summary

So, should you add insulation behind a medicine cabinet? Yes, but it depends.

If the conditions in the room aren’t extreme enough, you probably shouldn’t worry much.

If your cabinet is installed in a bathroom or any other room whose walls directly expose it to adverse temperatures and moisture, you should definitely add insulation.

If the cabinet is recessed, there is absolutely no point in adding insulation because it is partially installed in the wall.

This style of installation ensures that the wall protects it from moisture and cold air emanating from behind.

In fact, individuals planning to install their medicine cabinets in their bathrooms are often advised to install recessed cabinets for that particular reason.

The second thing to consider is the insulation state of your home – are your walls insulated?

If yes, what kind of insulation material was used? What is the R-value of the material?

You may stumble upon the insulation material as you dig in the wall to install your cabinet.

If you know everything about your home and you know it is insulated, there’s no point in trying to add another layer of insulation in your cabinet.

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