Concrete floors have quite some reputation for being so darn cold.
I can somehow deal with those in the summer. But it becomes unbearable when those freezing winter nights hit. On top of that, moisture loss through the roof in winter; let alone the lack of comfort.
But you know what- a wisely picked insulation for the concrete can put ends to all of these problems!
But buying the best insulation over concrete floor isn’t easy. Having said that, there are a handful of choices, all providing the ‘BEST’ insulation of your dream (marketing gimmick).
To cut the clutter, we’ve hand-picked 5 of the most dependable insulation mediums for your concrete floor, followed by a buying guide for honing up the purchase.
Seems promising? Let’s dive right in-
Comparison of Our 5 Best Insulation Over Concrete Floor
1. SmartSHIELD – 3mm 48″x50Ft Reflective Insulation roll – Our Top Pick
- EXTREMELY EFFECTIVE - reflect 97% of radiant energy, perfect...
- VAPOR BARRIER - Unaffected by humidity and moisture, can be used...
- SUPREME QUALITY - 3mm closed cell polyethylene FOAM (not a cheap...
- SOUND BARRIER - excellent soundproofing material.
- FIRE RATE - Fire rate Class 1 / Class A, NON TOXIC - will not...
The SmartSHIELD 3mm insulation roll from Insulation Market Place LLC managed to secure first place with its unique features.
While most foam insulation provides only a vapor barrier, this one kicked it up a notch. Along with complete protection from moisture and humidity, it allows fantastic soundproofing.
Other than that, it’s a tremendous radiant barrier. By reflecting 97% of sunlight, you can expect it to hold the heat for longer.
This effective heat retention becomes possible, thanks to the superior quality of the material. It comes with 3-mm closed-cell polyethylene foam with the aluminum wrapping on both sides.
However, I’m a suspicious man. So, I checked if it was really polythene foam or not. It’s not like air bubbles are bad in insulations, but it’s just for reassurance. Turns out, the manufacturer was telling the truth.
Overall, I’d say this you can rest assured installing this thin floor insulation on concrete floors. Speaking of thin floor insulation, don’t mistake lightweight foam as weak.
Even though it’s easy to cut and install, you’ll have a tough time tearing (yeah, I tried to tear it myself)
I can vouch for this insulation roll from garage floors to living room floors for many different purposes. That being said, if you’ve any further confusion, check out the product yourself in case we’ve missed any points.
- The pre-installed vapor barrier keeps out moisture and humidity
- Works a soundproofing material too
- Comes with pure aluminum on both sides
- Easy installation thanks to the lightweight build
- The recommended tape doesn’t go well with the insulation
2. US Energy Products 48 in X 10 Ft Double Bubble Reflective Foil Insulation
Next up, there’s a 48 in X 10 Ft insulation roll from US Energy Products. While it might not have soundproofing capabilities like the SmartShield- 3mm, but it gets the job done.
With its 2 layers of Polyethylene air bubbles, the durability game is quite strong. You can say there are 4 layers. 2 layers of air bubbles and another 2 layers of the aluminum film.
And it goes without saying that the 2 external aluminum layers are metalized polyester films. The best part is you don’t need any extra glue or tape to install. Simply nail it to the surface, and it’ll be good to go.
- Maintains heat with 2 layers of Polyethylene air bubbles
- Simple installation doesn’t require any protective gear
- Doesn’t need to glue to attach to the surface
- Emits only 3% of the heat
- Not quite flexible
3. Reflectix BP48010 Double Pack Insulation – Best Budget Pick
I’ve always faced one issue with insulation foams. People come to me and say, why’d you suggest this insulation roll? It’s not for insulating over concrete floors.
Well, allow me to clear out all the confusion. Whether it’s about insulation under concrete garage floor or a cooler (yeah, you saw that right), a good insulation roll will always get the job done.
If it holds the heat in your concrete floors, then it’d obviously be useful for other purposes, right? The Reflectix BP48010 Double Pack Insulation is that kind of insulation roll.
It’s an amazing foam insulation that’ll give you the best bang for the buck. I’m not saying it’s the cheapest one on this list. But when it’s about value for money, this one’s the champ.
Let’s say you want to turn your garage into a living space, but you don’t want to spend much on the insulation. My suggestion is, get a couple of these insulators to hold the heat.
With spending less money on these, you can actually focus on other essential items such as furniture or lights.
- Brings down the temperature by at least 10-degrees
- The double pack insulation holds heat efficiently
- Easy to cut
- The installation is a breeze
- The aluminum coating wears off after rough usage
4. US Energy Products 48″ x 100′ White Double Bubble Reflective Foil Insulation
- 48" x 100' White Double Bubble Reflective Foil Insulation Thermal...
This insulation from US Energy Products is a bit different from the other products till now. Have you noticed the white side of this insulation foam?
When it’s about laying insulation on concrete floor, this white part is ideal for that. It sits on the concrete floor without any movement. However, you’d have to make the necessary preparations (we’ll talk about it later) for that to happen.
The bottom line is it’s a great double bubble insulation roll that’ll hold on to the floor heat at all times.
- R8 thermal barrier reflects heat effectively
- Keeps out mold and mildew
- Non-toxic; no need to wear protective equipment while handling
- A bit pricey
5. US Energy Products 400sqft (48″ x 100′) Double Bubble Reflective Foil Insulation – Best Premium Pick
- Two layers of polyethylene industrialized air bubbles bonded...
- Non-toxic, non-carcinogenic, fiber-free, safe to handle and does...
- Not affected by moisture or humidity. Inhibits condensation
- Saves energy by reducing the stress on heating and cooling...
- Made in USA / Meets all International and USA Fire Codes /...
Finally, you’ve reached the final product on this list. I know you might be wondering why there are so many insulations from US Energy Products on this list.
It’s because they’re all different. It might seem they’re from the same manufacturer so there’s nothing significant about these. Well, the real story is a bit different.
This foam insulation is the most premium product by far. And as they say, good products will cost you some money. So, what’s so different about it?
Let me clear it out with an example. You know the number one issue users face with insulation under concrete floor slab?
They compress after some time. Obviously, there’s gonna be some kind of hard flooring above the insulation. And you can’t forget about the furniture and stuff.
That’s where the problem starts. While many insulations can survive even with a significant load, the insulation loses its effectiveness after some time.
But this one doesn’t have that problem. Put as much weight as you want, the insulation roll will still perform incredibly. And as we’ve already said, it won’t decompress any time soon.
- Lightweight but maintains industrialized strength
- Doesn’t have any fiber
- Lasts a long time
- Perfect for concrete floors as it doesn’t decompress
- The price might not be in everyone’s range
How to Choose the Best Insulation Over Concrete Floor?
Before you buy insulation for your concrete, you need to consider a few factors. In the long run, dealing with these issues beforehand will save both your time and money.
So, let’s see what’s in the bag-
Depth of Floor Slab
It’s not hard to figure out why the floor slab’s depth would play a significant role here. Choose thicker insulation and you’ll need to have a deep floor slab. But that gets a bit easier when you insulate over the concrete floors.
Although the more concerning factors are what’s above the slabs. What I’m trying to is you’ll need to see if something’s getting in the way of the insulation. Other than that, cleaning out the dirt and debris should be enough.
Material Under Concrete
The material under the concrete is a huge deal when it’s about the insulation’s U value. Let me paint you a picture.
Suppose you have clay as the material. Now clay having low thermal conductivity won’t allow the heat to escape. While rock or sand lets the heat out a lot faster.
The bottom line: depending on what type of material you have beneath, you need to make sure the insulation has the right U value.
Anything that’s beneath the floor needs to have some sort of load-bearing capacity. Although it widely varies depending on the type of building you have. For industrial buildings, it’s better to stick to the heavy-duty stuff.
On the contrary, you don’t have to deal with heavy-duty material for residential buildings. Lighter insulations should do just fine for these buildings. Especially when it’s about insulation over existing concrete floor.
Things get a bit complicated when you’re thinking about installing underfloor heating. It’s nothing serious but you do have to rethink the placement of the insulation.
You’ve got 2 options. You can put the insulation over the concrete slab or it can go under the slab. Regardless of what you choose to do, the heating has to be within a creed.
Why Should You Insulate Concrete Floors?
Many people still think insulating concrete floors is pointless. Well, it’s kind of like painting your basement walls, you need it for moisture protection.
Nonetheless, I’ve gathered 3 major reasons why it’s vital for you to insulate your floors.
Pour some water into a plastic container, the water won’t be going anywhere soon. But do the same on a concrete floor and you’ll find no traces of the water after a while.
So, what’s the matter?
Well, concrete floors might be reliable in durability. But that doesn’t mean they’re not porous. Whether you get a carpet or install laminate boards, the moisture will still find its way to get out.
That moisture will result in mold and mildew unless you take care of it ASAP. Speaking of mold, something came to my mind. Whatever you do, make sure don’t leave any void under your stairs.
Moving on. The easy way is to get some insulation. Get those installed and the moisture will stay there.
Apart from that, a lot of insulation comes with vapor barriers preinstalled. So, good news for the DIY guys.
No Heat Loss
If you’ve got no insulation in your building, you will LOSE a significant amount of heat. In fact, when we put it into numbers, you could lose around 30-35% of the total heat.
Imagine how much money you’d save on your heating bills if you took care of that. Forget money, you’d live much more comfortably with proper insulation.
Although newer buildings have to be built with proper insulation. But the problem is contractors tend to use R5 and R10 to do it. Long story short, try to get R20 insulation for your building.
The greater the R-value, the better the heat retention. However, you have to consider the material under the concrete too. Remember what we talked about a while ago?
If it’s sand or rock, go with the better insulation. And for clay, R20 insulation should be more than enough.
Putting in some insulation can change the overall temperature of your house. You can feel it when you go to a house with no insulation.
I don’t know if you’ve noticed but concrete floors feel cold even with hard flooring on top. With proper insulation, that cold feeling will be long gone.
Anyway, that’s been it. I honestly feel these are factors everyone cares about. If this isn’t enough to convince you, I’ll see if I can come up with anything new.
How to Insulate Over Concrete Floor in 6 Steps?
You already know why it’s necessary to insulate concrete floors. So, let’s get straight to how you can insulate a concrete floor-
Step 1: Prepare the Floor
Moisture, uneven surface, and dirt are the 3 things you’ll look out for when preparing a concrete floor for insulation. This also includes repairing any bad jobs.
Other than that, remember to have a smooth floor before you start the job.
Step 2: Measure Distance between the Floor and the Ceiling
Whatever you do you’ll have to ensure 7 feet and 6 inches gap between the floor and the ceiling. Unless you want trouble with building codes, it’s crucial you maintain it.
Step 3: Apply Asphalt on the Floor
First, apply a layer of asphalt primer. After it’s dried, you can put in asphalt mastic on the floor. A gallon should be enough for a 100-square feet area. So, figure out the amount you’ll need.
Now, give the asphalt some time to dry. Then, 6-mm polyethylene all over the concrete floor. It might sound a bit weird but you’ll have to walk over the polythene to ensure there aren’t any air bubbles.
As a bonus, this will also ensure better adhesion of the asphalt.
Step 4: Install 2-by-4 Sleepers
Put down 2-by-4 sleepers on the edges of the slabs. Additionally, use 2¼’’ masonry nails to fasten those.
Step 5: Put in the Foam Insulation
Install 1½’’ foam insulation within the slippers. Look out for the right measurement of the insulation. Otherwise, the performance won’t be up to mark.
Step 6: Install Plywood Sheets
This one’s quite simple. Place ¾’’ plywood sheets all over the floor. Finally, put in the flooring you want and it’ll be done.
How to insulate concrete floor before pouring?
Install 2-inch-thick foam insulation all over the floor. After you get the measurement right, remember to put waterproof tape to hold everything together. Now, the floor is appropriately insulated and ready for pouring.
Is it worth insulating a concrete floor?
Being bad at heat retention, concrete floors generally stay cold. Most people who insulate concrete floors notice a radical change in the overall temperature. Besides, the heat takes comfort to another level.
What is the minimum thickness for floor insulation?
The minimum thickness for floor insulation would be 70 mm. But keep in mind that 70-mm is the bare minimum. If you want better heat retention, go for higher-performing insulation.
Why is concrete a bad insulator?
Long story short, concrete has a lower R-value. It’s something people use to measure thermal resistance. That’s why you notice that most concrete floors are usually cold.
You can’t think of concrete floors without decent insulation. However, it’s not like you have to get insulation. You can choose to live with cold feet (literally).
Otherwise, the in-depth analysis I gave them above should be enough to get you started on your insulation. So, I hope you figured out the best insulation over concrete floor. If there’s anything else you’d like to know, give me a knock and I’ll be there.
Valerie Henry says
Hello I just read your article and I have a few questions to ask regarding insulating concrete floors