You might want to proof read that again, Bob.
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The best solution is to not build a single wythe masonry wall, especially in Chicago.
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If it is already built, here are the necessary details:
- Small exterior cracks should be sealed using Vulcum caulk.
- Seal exterior with a polyurethane, “plugger” type paint applied according to the manufacturer’s specifications (flood coat).
- Make sure that the parapet walls are properly flashed at the coping. Through wall flashing (IPCO) is stainless steel drip edges.
- Make sure that all joist pockets are properly through-wall flashed with weep wicks.
- The joists flashing should extend out from the block, again stainless steel drip edges are preferred.
- Interior furring strips should not be in direct contact with the masonry. Never have wood in contact with masonry, HI # 101.
- On the interior, insulation should be closed cell spray foam.
- The underside of the roof decking plywood should be coated with open cell spray foam as a vapor barrier and as insulation.
Here’s my verbiage:
If the place looks OK (no water intrusion detected):
“While not properly installed or equipped with the properly installed and required joist pocket flashing, the split faced block is properly sealed and water intrusion was not present through the masonry at the time of the inspection. Recommend that the block be evaluated and, as needed, properly and professionally sealed, either with a penetrating sealer on a 5 year schedule or with elastomeric paint as a guard against water intrusion through the block. Recommend that the work be done by a licensed and insured masonry contractor with experience with split block maintenance and that a regular maintenance schedule be established.”
If not OK:
“Recommend that the exterior wall split faced CMU be sealed against water intrusion. The current best product for this is an elastomeric plugger type paint. Recommend that the repair and sealing work be done by a licensed and insured masonry contractor with specific experience dealing with split faced concrete block issues.”
Also make sure that the coping is properly flashed and that they did not take the roof membrane up-and-over the parapet wall. This makes the interior portion of the parapet wall “inside”, i.e., compromising the building envelope.
I have a guy who I have been working with who developed a breathable coping, as well as a breathable termination bar. But as you know, flat roof roofers around here never learned about counter flashing above the ternination bar.
And, if the roof is sloped (i.e., no parapet wall), there is usually no problem.
See this article for more information:
Hope this helps;