How old is the house? How thick is the concrete slab? What are the walls of the foundation made of (concrete or brick)?

Toronto basements are notorious for being problematic and/or porous. Why? Because they are often old homes with thin concrete slabs in the basement and mason block for the walls.

Finding where the moisture came from is the way to figure out how much money you have for renovations. Vinyl plank floors REALLY need smooth and flat. To get these old slabs flat, there might need to be some HEAVY grinding PLUS adding more concrete to level it out.

For these reasons alone many people simply put down more carpet and keep going. The cost to get anything else in there is EXTREMELY high (ahem...imagine having to jack out the old concrete, dig down another 6-12" and then pouring new concrete). Nope. Not kidding. Just watched a "Holmes Inspection" on TV with EXACTLY that requirement. In T.O.

Whew. First things first. How old is the home?

I believe the home was built in 1918 approximately. It is in the Davisville Mount Pleasant Area. The outer walls are brick.

Look into a product called LevelQuik RS 50 Self-Leveling Underlayment. Or a similar product.

Yes it is expensive. But it is the best and simplest way to level a concrete floor without adding a lot of bulk (height) to the floor.

Ahhhhhh. The '1918' and the foundation 'walls are brick' tell me all I need to know. I'm going to guess you have a 4" slab (very thin) without any vapour barrier (there weren't any at that time) and the brick is leaking like a sieve. Brick is POROUS. All it takes is too much moisture in the ground SURROUNDING the brick and you get moisture penetration.

Moisture follows the path of least resistance = follows gravity. It gets into the brick and then drops down to the floor level and then sits there gathering as puddles. The puddles eventually turn into 6" worth of standing water.

Please call out a moisture mitigation company that specializes in masonry foundations and OLD houses. Please be prepared to remove the concrete slab if they find some nastiness that has contributed to the excess moisture.

Before you call, please sit down and speak with your financial advisor and find out your ABSOLUTE LIMIT for a homeowner loan. It will need to be in the high 5 digit range if the entire basement has to be redone/dealt with. That loan will also have to have the refinishing wrapped up inside of it as well. The refinishing part will be the least expensive part. The most expensive will be the moisture mitigation - with the possibility of full excavation of the basement slab.

Remember the motto: Be prepared.

PS: the good news being if you HAVE to excavate the slab, it doesn't cost much more to dig out a bit more dirt to give you a proper 8' ceiling height. Then you never have to worry about the ceiling height again.

I used LevelQuik to level our basement bathroom before we installed tile, and it works very well. However, it would be very costly for a large area if you have to do more than a very thin coat. You can price it at HD for about $30 per 50 lb bag, and calculate how many you need. If you are way off level, a few bags will not go that far.

You mix it up in buckets or a wheelbarrow, and then pour it on the floor, It has a consistency similar to cake batter. You can use a wide rubber trowel to encourage it to fill in all directions, but gravity does most of the work. You must have something on all sides to enclose the area because it will literally run and self level until it hits a barrier. I used RS, and it was dry and ready for the tile installation within a few hours.

Also, the RS in the name is Rapid Set, and they also sell ES, or Extended Set. RS is great because it sets up completely in less than 4 hours, but this means you really need to have the right amount on hand, and you need to mix it quickly if you are doing a large area. If you run out of RS product during the job, there is no time to run to the store and buy some more before it starts to set.

I would stick with painting the floor and using area carpets. Old basement floors usually did not have a moisture barrier under them, so there will be a small amount of water vapor coming up through the slab forever. Vinyl tile may hold up fine, but repainting cement is really easy if there are any further water problems.

Bruce