Invisible

Yes, our waterproofing is invisible…  Not just clear like I expected from the description on the bucket, but actually imperceptible.   You can’t even feel it.   So we were not that surprised when our building inspector questioned it.

We had used ProtéShield made by New Look International.  Actually, we bought it from Home Depot. Our shotcrete walls are curved and not the smoothest in the world, so it was important that we use a waterproofing that we could spray on.  ProtéShield claimed to be, “a water-based inorganic elastomeric polymer sealer designed to penetrate, waterproof, seal, and protect various porous surfaces.”  The website said it was, “Recommended for sealing, waterproofing, winterizing and protecting most porous building materials such as concrete, pavers, concrete block, brick, precast concrete, plaster, drywall, GFRC, gypsum board, stone… [etc.]”  The brochure listed, “Ideal Interior and Exterior Applications: ” including, “basements and other below grade spaces.””Foundation walls (above grade and below), bridges, sound and barrier and retaining walls, fencing, towers, buildings.”  Their technical data sheet claimed ProtéShield would protect the concrete against, “ultra violet rays, ice, water, chlorinated water, salt water, rain, acid rain, salts and other chlorides, rust, mold, fungus, insects, chemicals, oil, fuel, stains, and excessive temperatures.”   The cost was about $270 per 5 gallon bucket and I would need 2 buckets to get the basement walls done.

So, when my building inspector questioned it, I brought out the empty bucket and showed him what we had used.  He said he had never heard of it and would need to see the official test results.  No problem, I emailed him the technical data sheets (Sherri found them with her new smartphone).  He gave us a partial approval on the waterproofing and said we could proceed with the back-fill at our own risk.  He would check out the data sheet, but if it had not been properly tested, we would need to fix it (dig it up) before proceeding with any other steps.  It was a tough decision, but I was sure it would pass and the excavators were due to arrive any moment to work on the back-filling.  We went ahead with it.

A couple weeks later, my building inspector emailed me that the correct tests had not been done and we were not approved for backfill…  I called New Look International and asked them about it.  They said they had never been asked for that test before but insisted that they test their product and it would work for me as described.   They called the building inspector to talk to him on my behalf.

Test and verify

The next day, the building inspector called and told me about this part of the building code…

R104.11.1 Tests. Whenever there is insufficient evidence of compliance with the provisions of this code, or evidence that a material or method does not conform to the requirements
of this code, or in order to substantiate claims for alternative materials or methods, the building official shall have the authority to require tests as evidence of compliance
to be made at no expense to the jurisdiction. Test methods shall be as specified in this code or by other recognized test standards. In the absence of recognized and accepted test methods, the building official shall approve the testing procedures. Tests shall be performed by an approved agency.  Reports of such tests shall be retained by the building official for the period required for retention of public records.

He said that he would allow me to conduct a test of the waterproofing to establish if it was acceptable or not.

I designed two tests.

My first test was based on other damp proof tests I found on YouTube.  These tests place the lower end of concrete samples in water and see if it is drawn up into the sample.   I used pieces of shotcrete that had ended up stuck to my bracing.  I waterproofed half the samples and made this video.  I think it worked well in this test. (no music because testing is serious ;^)

Then the second test was against gravity… I made two concrete bowls from ready mix with fiber reinforcement. I waterproofed one and then filled both with water. The hope was that the one would hold the water without letting it soak in or drain thru. Clearly, the waterproofed bowl did much better than the other bowl, but, perhaps due to the small bubble holes on the surface that did not get properly filled with waterproofing, water did leak into the bowl (the water level dropped). Here is the second test video.

Conclusion

I sent both videos to my building inspector and he approved the “damp proofing” on the vertical basement walls. That was a big relief because it would have been expensive to dig it up and reapply.  However, he didn’t feel comfortable calling it waterproofing for the horizontal roof of my earth sheltered building.  I agreed to use a more visible waterproofing for that.

On to the next challenge…