How to seal an existing basement floor
user-901114
| Posted in General Questions on
I have daylight/stepped foundation basement floor in zone 6 that has heaved and hod over the years due to it being unconditioned. It’s about 15 years old but has been in the elements for most of them until I purchased the property and put a frame on it. It’s got cracks along the perimeter and in the floor and I’m wondering what my options are for sealing them. Thanks, Steve
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Budget, and why fixing, and what are you going to do with the space?
Radon control, insulation, building a living space, what?
Usa need ta do some splainin.
Stephen,
If your basement slab heaved due to frost action that happened when there was no building on top of it, then it's hard to assess what you need without a site visit or some photos. You may have just a few cracks -- something that can be patched with caulk or a special grout used for slab repair -- or you may have a heaved slab that is broken into pieces and is no longer level.
In the latter case, it may be necessary to demo the slab and pour a new one.
Budget is low. This is my summer camp. I think they are just cracks. Not big breaks. Will be used as a shop. There are several PVC pipes but I'm not sure if they are for radon. I've got the beer if you ever get over to Squam lake NH! I can't get pics right now but will when I get all the bags of roxul out of there...
Stephen,
HD has what you need. For now low budget, you need latex modified mixes. for tight joints you need latex modified thin-set at $6/bag. for wider cracks you use sand filled latex modified mix from the concrete aisle. For even larger cracks use concrete that has stone in it and add latex or buy something that has latex. Concrete that is modified with dry additives that are modifiers cost much more than the $3 bags... $15-30 per bag and come in all flavors. If you read the labels, the ones that build to thicker dimensions will work for wider cracks. The ones that say they can be used down to zip thickness will work in tight cracks. Prime the cracks with straight liquid latex additives, let the latex dry to tacky or more. Concrete always should be primed with liquid latex to get the best bite. Cleaning with acid is difficult and if you do, you need to rinse the acid away and really give it lots of time for the area to thoroughly dry. So really, forget the acid wash.
I patch tennis courts, cracks are a joy, really. We mix standard concrete with straight liquid latex. to fill cracks. If anything moves, the crack comes back, but we have a neat cover we use now to hide the re-cracking. For inside non freezing floors, you will be in better shape. The pros fix cracks with epoxy made suitable for concrete. HD does sell tubes of the stuff and it is great. I have used it. I would not use it though if I had to buy a hundred tubes of it for a billion feet of crack. One tube will do several feet but not tens of feet.
Beer worthy post?
Six beers worthy AJ. Thanks for the tips.