The Green Foundation Contradiction

In our area, there are several contractors considered to be the “green building” leaders. They market themselves as the innovators of the green building movement, but actions do speak louder than words.

After recently seeing several ads in a local publication, I decided to do some online research of the companies touting their green building expertise, especially as it relates to foundation construction. One builder I researched includes an asphalt waterproofing membrane on all jobs. Another indicated that a Platon sheet membrane was their choice of basement waterproofing.

Anyone versed in green building should know that Platon is a better choice when wanting to build “green” because it is manufactured with a high level of recycled content. My impression was the company offering the Platon probably does have the better grasp on how to build in an environmentally friendly manner.

At the same time, I thought to myself, wouldn’t it make the most sense to build a foundation correctly so that waterproofing isn’t a necessity? That’s what makes sense to me and that’s our goal at Coello and Associates.

As far as I know, the same builder using the asphalt-based waterproofing on all projects also chooses to use a foundation contractor that is known for its low cost, not its high quality. This contractor substitutes industry’s best practices with waterproofing as a band-aid to keep the basement dry. These foundations lack the needed steel reinforcement, control joints, and proper consolidation techniques required, so a waterproofing membrane is added to protect the contractors when the walls crack.

Adding an asphalt based waterproofing membrane is not an environmentally friendly practice. To market that sustainability and “building green” are your main objectives, but to make this a standard inclusion, seems wrong on many levels. There are some things in building that are absolutely necessary, but may not be “green”. Waterproofing is not one of these things.

For the sake of full disclosure, I do admit that our company does make waterproofing available to those who want to add it, but this is not a standard inclusion. We see the waterproofing as an insurance policy owners can buy to extend the warranty on their foundation. On a bit of a side note, the product we offer does have a transferable warranty that will cover the repair of the leak. This is a good thing. Not all waterproofing warranties work this way. Others warranty only the product itself, so if a leak occurs, more of the same material would just be applied to the problem area. The term “dry basement guarantee” tends to be thrown around a little too loosely if you ask me.

There’s no denying that having a dry basement is important, but that’s not the only thing to consider. The foundation must support the loads applied to it. In order to do this, the industry’s best practices must be followed and reinforcement in the foundation is a must. The most “green” quality of a concrete foundation is how long-lasting it will be if poured correctly and in a manner that works with the conditions of the building site. Unfortunately, this is often ignored in favor of a focus on the short-term, meaning adding waterproofing to cover up foundation construction flaws.

Homeowners must really do their research when choosing a builder. Some builders are great at marketing themselves, but don’t necessarily build a great house. Just because the builder touts their green principles and can meet LEED guidelines, it does not mean they are following through on the true promise to be green.

Control Joints in Foundation Walls

Perspective is a very interesting concept. Depending on how you perceive something will drastically affect your logical thought processes. What does any of this have to do with concrete? Well, when it comes to the importance of control joints, it relates very well.

Industry professionals and lay people alike seem to get thrown on the importance of control joints in vertical concrete. Almost all parties agree that concrete slabs need joints to help control where the concrete will crack on flat slabs. However, those same people will not relate to the importance of control joints when the concrete is standing up. Their perspective due to the concretes orientation is different.

Whether concrete is vertical or horizontal it shrinks and cracks during the hydration process. Just because it is vertical does not mean the concrete is under some other mysterious force of nature that prevents it from cracking. A foundation crack is more serious due to the fact that now a place for water to get from the outside is present. Therefore, the installation and drainage details are vital to the performance of the concrete foundation wall.

I have encountered two examples of people realizing the importance but not willing to actually follow through with the details. One example was in a discussion with a vendor a few months back. The vendor was a national corporation selling asphaltic based waterproofing membranes. He called to explain the benefits of his product over our current Tremco Barrier Solutions Tuff N Dri product.

His first sales pitch was delivered in a question. He asked how many foundations we did, how many were waterproofed and what percentage had water intrusion call backs. When I gave him the answer of about five to ten percent were waterproofed and less than one percent had a call back I heard total silence. He then began to query me on how our company could have such great success compared to all other areas of North America. I explained to him about our “Integra” foundation system with the steel reinforcing, concrete mix design, consolidating techniques, and the control joints with the water stop system. Once complete with the explanation he stated that there was no need for him to call us anymore. His waterproofing membrane could not add any more value because we had developed a fool proof effective system. The key, he said, was the control joints and water stop and most people’s perspective is to add the waterproofing band aid and transfer the risk of failure to someone else instead of doing it correctly.

The second example came during a site inspection of one of our foundations. We had just completed a foundation in a newer subdivision and a competitor did a foundation next door. I went over and checked it out. The foundation had just been completed a day earlier and the job was ready for backfill. The thing that jumped out at me was that there were no control joints in the foundation walls. I knew the competitor and that practice was fairly common. A few weeks later when I was in the same subdivision again I stopped back at the freshly backfilled site. Someone must have requested control joints to be cut into the foundation.

Now control joints are good when done per industry standards. However, these were not. What they amounted to was a faux control joint. The joints were only on one side of the foundation, were a total of less than three eighths of an inch deep on a nine and five eighths inch thick wall, and no water stop or waterproofing was done. Standards call for foundation wall control joints to be either formed in or cut in within forty eight hours of the pour, the joint needs to be as deep as twenty five percent of the total thickness of the concrete, should be on both sides of the wall if possible, and some type of water stop or waterproofing should be done so the foundation does not leak when the joint cracks. Now in the eyes of the owner he got a control joint. How effective it will be will be determined over time.

No matter what your perspective, the only way to do concrete right is to put in control joints. If the control joints are in a concrete wall, please make sure they are not an illusion but actually are a functioning part of the overall foundation system.