Can I transform my 1987-built unfinished cement basement into a usable space by applying a protective barrier over the floor?
Asked by Blagoje Majstorović 
3 weeks ago
Last Updated: October 30, 2024
Do you think it’s possible to convert my unfinished basement with a cement floor into a family room or laundry room? My house was built in 1987 and I’ve been doing some research online. Some sources are saying it might not be possible because of the age of the house and the lack of a water barrier under the floors. Can I just put a protectant over the cement instead? It would be such a shame to have all that space go to waste. I could send you some pictures if that would help.
I completed mine. I actually transformed it into my bedroom, even though it was initially meant to be a den with a fireplace. My house was constructed in 1971 with a concrete floor. I never experienced any issues.
You can definitely do it, just make sure to take some extra precautions.
The house I live in from 1971 is built on a concrete slab & I put down Pergo flooring with a plastic vapor barrier. And everything has been problem-free!
Go ahead and start building. Homes in that era typically utilized a vapor barrier beneath the slabs. 6 mill poly plastic
Whoever informed you of that was quite misinformed.
Check out this link. Or, you always have the option to apply spray foam to the walls.
https://www.finehomebuilding.com/2005/03/01/the-no-mold-finished-basement
Another option for flooring finishes is to use tiles with a plastic Schluter membrane. Just keep in mind that it may feel cold.
Who mentioned that? In Canada, basements are typically designed to be finished eventually; a house from 1987 is still relatively new!
If the house was constructed properly in ’87, you should have a French drain surrounding the house, gutters and downspouts directing water away, the ground should be sloped to prevent water from pooling, foundation should be waterproofed, basement window wells, and a check valve. (Building code requires a rough-in for a toilet in the basement).
All of this applies even in non-flood zones.
I realize that construction practices can vary widely in different regions… This is how we’ve been doing it in the northeast since at least the 70s.
If you’re not having any water issues at the moment, then you should be good to go.
Here in Nova Scotia, we frequently install laminate flooring on concrete, often using foam underlayment or foam backed flooring
In my 1964 basement, we finished the floor with concrete stain and sealant. There doesn’t seem to be a vapor barrier underneath, and we’ve had bedrooms down there since the house was built.
I did this in my 1951 home. I have a fan running on a timer to keep the air circulating and a dehumidifier for 8 months out of the year. Mine is approximately 6 feet below ground level.
Consider using Delta-FL or DMX 1-Step underlayment for your flooring!
It’s your place. If you don’t have any moisture problems, go ahead. Just keep a dehumidifier on and make sure to heat it during the winter. Try taping a piece of plastic wrap on all sides of the floor for 48 hours to check for condensation. If there’s none, you should be fine. Worst comes to worst, you can always live with a painted concrete floor.
The garage in my 1964 house was already turned into a living room before we bought it. They simply placed a vapor barrier on the concrete, followed by a 2×4 frame for a bit of cushioning, and then the subfloor. Moisture has never been an issue in that room.
If there are no water intrusion problems, go ahead. Make sure to add the right vapor barrier for your flooring choice and either condition or dehumidify the area.
Thanks for all the great suggestions! I had heard that homes built before the 90’s might not have a barrier and would be difficult to build on. It’s nice to know that’s not always true!
https://www.homedepot.com/p/DRICORE-Subfloor-Membrane-Panel-3-4-in-x-2-ft-x-2-ft-Oriented-Strand-Board-FG10006/202268752
You should try this product. It’s the best option available, as it includes a vapor barrier, standoffs for air circulation, and provides a cushioned feel. Plus, it has tongue and groove for easy assembly.
Does know if this can help smooth out cracks in concrete? I’ve heard that LVP requires a very smooth surface, for example.
This is a form of underlayment that is installed beneath LVP or carpet. If the floor is not level, it’s best to opt for hardwood or carpet instead.
I’ve installed flooring in a bunch of homes – ceramic tile, luxury vinyl, even plank flooring with a carpet border. Feel free to do whatever you want with your floors, just watch out for moisture or leaks.
You can do a simple test yourself. Purchase plastic sheeting and duct tape, create a 6x6ft square of plastic, tape it down securely on all sides, and wait a few days. Do you notice any moisture? Answer yes or no.
If yes, then you’ll need to address that issue. Consider sealing the floor or exploring other solutions.
If no, then you can proceed without concerns.
In my own finished basement, we encountered no moisture problems despite not having a vapor barrier under or over the concrete during the finishing process.
In my opinion, this is something that should be taken into consideration year-round. Our concrete floor only sweats during the rainy seasons.
Suggested they could keep an eye on it for a year or simply use a dehumidifier in the basement once it’s done.
Do you happen to have a sump pump? I would also recommend checking with your neighbors. My brother-in-law’s basement and garage used to flood every year until they moved. Our home stayed dry except for one corner where the shower was located, so we may need to consider building because bathrooms are prone to getting wet!
We redid our basement, can you tell me how high the ceiling is?
We found the same details before the remodel and everything went smoothly. Our current home was constructed in 2001
Our lower level
The house I previously owned was built in the 1970s with no issues…now preparing to update my new 1960s home…it really depends on the soil and a few other factors, but both of mine had sandy soil which allowed for good drainage
We completed interior waterproofing. No issues with moisture on the floor. Surprisingly, many new construction projects I’m involved in skip using a vapor barrier under concrete when finishing basements, with no problems.
About 50% of the houses in my town were constructed prior to 1940.
Almost everyone here has a basement that’s been finished.
Our house, constructed in 1976, has a vapor barrier beneath the concrete. It’s difficult to determine without tearing up the floor, which may not be ideal.
Before converting the space into a living area, make sure to verify the codes for exits, windows, and doors.
Why not try this experiment? Cover different parts of the floor with plastic, a 4×4 rug, or cardboard for a few days. Make sure to check after a rainy day to see if any moisture accumulates underneath. This will help you decide how to seal it properly.
Just sharing my personal opinion, I enjoy DIY projects too.
Absolutely, focusing on the window and door codes is definitely your top choice.