Waterproofing an older concrete foundation

rapsonite · 07-19-2008, 03:02 PM

Hi
I own a 1927 pre Portland cement era house. My foundation is concrete with large aggregate -- stones found during excavation at house building time I guess. There is some water infiltration and humidity in the basement. I'd like to repair, waterproof and insulate the walls and install an weeping tile and sump pump, so that we can finish and use the basement. The humidity is not a problem in the winter but in summer months we run the dehumidifier all the time (we are in the Ottawa Canada area)

I've had several foundation repair companies give me quotes, and prices as well as techniques vary quite a bit. Some recommend using Platon (the rigid dimpled plastic sheet product) some say Bakor 77006 (a sort of liquid rubber product that adheres to the wall) is the way to go. The wall surface is super solid in spots and brittle in others. I am not sure what is the best technique between the two. How to ensure a good adherence of the waterproofing product and the existing wall? How to ensure you don't further damage the wall when nailing to it etc? How to ensure water doesn't get trapped and make things worse...

Thanks for any experienced wisdom.

Janine

buletbob · 07-19-2008, 05:19 PM

Are you talking about doing this waterproofing from the inside. if so why not start from the outside. If you have no water coming into the basement now and just humidity why are you installing weeping tile and a sump pump?. I thinking just look to stop the moisture from coming through the walls. I would excavate and power wash the foundation and install the waterproof membrane 4" above grade and down on top of the footer and over the bottom edge.
I don't know your site layout, but if it was my house I would be more concerned on having the moisture getting into the concrete. I hope I understood your above post.
BOB

rapsonite · 07-19-2008, 11:58 PM

Yes, I am talking about waterproofing from the outside. A bit of water as well as humidity come through the walls. You say to power wash the foundation and install the waterproof membrane 4" above grade and down on top of the footer and over the bottom edge. But what kind of membrane is best for an older rubble concrete wall? One company I spoke to proposes the Platon product (a rigid panel that needs to be nailed or screwed to the wall) and the other the Bakor product (a mastic that is brushed directly onto the wall), as I explained in the first post. By the way, this house, built circa 1927, has no footings. I am told this is typical for this area at that time. Also, what is the goal of power washing?

Thanks again for any advice.

mgsproperties · 07-20-2008, 01:51 AM

Try French drains and pulling the water away from the foundation. You can also apply Henry’s tar after the French drains a very cheap solution

buletbob · 07-20-2008, 07:44 AM

Quote:

Originally Posted by rapsonite

Yes, I am talking about waterproofing from the outside. A bit of water as well as humidity come through the walls. You say to power wash the foundation and install the waterproof membrane 4" above grade and down on top of the footer and over the bottom edge. But what kind of membrane is best for an older rubble concrete wall? One company I spoke to proposes the Platon product (a rigid panel that needs to be nailed or screwed to the wall) and the other the Bakor product (a mastic that is brushed directly onto the wall), as I explained in the first post. By the way, this house, built circa 1927, has no footings. I am told this is typical for this area at that time. Also, what is the goal of power washing?

Thanks again for any advice.

I must of over looked your first post saying that there was some water infiltration. Yes I agree with the drains then. If its a rubble foundation then the power wash and brush on water proof would be better. Power washing would remove all the loose dirt from the wall so the waterproofing will adhere better. Check this link out it should help http://www.bakor.com/waterproofing_coldapplied.asp