Expert: Dan Griffin - 12/16/2008

Question
I come across homes in the upper-midwest where the home has stucco applied right down to final grade or within 1-2" of it. The problem I run into is that if the customer wants me to install a patio that will still properly drain away from the house, either the entire yard would need to be re-graded or the pavers and sometimes the base material as well would need to contact or rest against the stucco.  From everything I've heard, touching stucco is taboo.  Are there any methods/techniques you may know of on this topic that would allow me to build the patio with the top elevation above the bottom of the stucco without potentially causing water problems in the home or behind the stucco.

I would like to thank you ahead of time for any advise you may have on this topic.

Answer
Josh, you have the facts pretty well right.  The stucco/ EIFS is often installed to cover the gap between stem wall and base plate.  I've never understood the builder's intention when minimizing exposed stem or grading with minimum falls.  Architects do the same thing on commercial sites when raising the structure 6" to a foot would make everything work so much better, but they never want to spend a dime on an unseen issue which most people will never see.  Most patios need to be down one step below finish floor.  It would be unusual to be able to deal with water proofing if the exterior was the same elevation as the interior.

I cannot recommend running concrete against stucco or EIFS.  If you violate the drainage plane which we both hope is there you're headed for the the quagmire of mold, mildew and condensation damage.  If the stucco/EIFS was run low simply to hide most of the stem, it can be cut up higher to allow the patio/sidewalk work.  It would be best to have a stucco man involved to trim things out correctly.

Be honest with your customers.  Warn them about trapped moisture issues.  If they want to pursue the work, make sure you disclaim in writing.  The issues and lawsuits are well documented.  I have a good friend who insisted on pouring against aluminum siding.  The work was done almost 6 years ago and nothing bad has happened yet that I know about.