Solid Concrete vs Cement Block Foundation
My husband and I are starting construction on a home in the Central New York Finger lakes region this summer. We plan to GC the project ourselves. We are seasoned project managers (40 years between the two of us) just none of it in construction. We have some type of experience in just about every facet of interior finishing, but not much regarding the building assembly and foundation. There are a ton of decisions to be made, and being the detailed/anal retentive person, I am trying to learn what I need to know to make those decisions wisely. Meanwhile my better half looks at the plans with stars in his eyes and can’t wait to move in. That said, I have tons of questions, but will try to ask one at a time and continue to do research as I need to pace myself and I am still learning the construction lingo.
Guess I should start from the ground up…we are getting quotes on a concrete wall foundation and block foundation; my husband is leaning towards block as he says it will do the job and cost less. That may be correct, not sure, but the mason made a comment that has been weighting on my mind for weeks; he said, “I’m old school. I only use…(can’t remember the word might have been parge) and tar paper”. I have immersed myself in blogs and articles on this site, and have not seen that concept mentioned. The other issue I have is that we are putting hydronics in the slab, and I would prefer someone to pour the slab that has experience doing it over hydronics.
Do I have reason to be concerned?
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Replies
Nina,
I suggest you search for "pretty good house" on this site and read all the related articles and discussions. I suspect you and your husband want a house that is comfortable and efficient without being overly expensive. The pretty-good approach can get you there.
After 40 years or so or experience, I'll just say that sub-contractors like to run the job for you. Of course, each one will run it so it is to their advantage.
For example, I've been told at times (when I was younger) "Yes, I'll do that later." Same thing again when I asked them to do it a second time. Finally they said, "Oh, it's too late to do that now. You should have mentioned it earlier." A classic around here is, "I've been doing it this way for years, and no one has complained yet." Why would someone who is relying on them to be the expert complain?
Point is that the person running the job has to know enough to enforce best practice. Not only know about each trade in detail, but also how they all fit together. The person running the job knows what will come later, the trades only know what they are doing for their small part.
Hire a contractor. You'll get better results, save yourself a lot of headache, and avoid catastrophes that could cost more than you will save. Trying to build a house yourself seems to me like trying to become an accomplished and professional French chef to cook one meal.
Steve, Thank you. I will read them all.
David, I understand your points completely. The person, who will be framing and drying in the home is a friend and has been building custom homes for years, but he does NOT like being a general contractor, he likes to frame, particularly timber frame, but does not mind to dry in the structure completely, and we know he will do an exceptional job. If we can get though the foundation portion and a couple of decisions on insulation, the remaining contractors (electric, roofing, sheet rock) are mostly friend or people who have completed jobs for us in the past and are very willing to work on this project, and we trust them or they come highly recommended and we fill confident in those choices. As for the rest, painting, tiling, plumbing, etc..most of the interior; these are jobs we have the skills the complete.
Even on the insulation, our architect and builder are providing us with valid solutions, most I have seen on this site and the building science site, but I need to be able to afford this home. I do not want to show any disrespect to these two men, so before I ask questions or ask for alternative solutions, I read, research, just recently started asking questions here, so I have a better understanding of why they recommend what they do. Not to mention, I can't afford to pay them by the hour to educate me, or I definitely couldn't afford to build a house.
On concrete, I know no one in the trade. We did mention to the architect and builder we were considering concrete block. We got the raised eyebrow, and then went back to the topic at hand, and I did not have time to bring it up again.
We looked for a while for contractors, who would be willing to just handle the foundation and building assembly, but the only companies willing to do that were log home builders. When our friend said he would gladly do the timber framing, stick framing, dry the structure in, and even do some of the indoor carpentry (he also designs and builds beautiful cabinets) we though we hit the jack pot. All we had to do was handle everything else...and that is where we are.
Tens of millions of buildings rest upon foundations made of mortared concrete blocks, bricks, and even stones. Breathe easy. I would not hesitate to go with CMU foundation walls if it saved a substantial amount of money over solid concrete.
Nina,
There is no real case to be made that a CMU foundation is as robust as a poured concrete one. Their widespread use without significant problems show that they perform alright - that they are good enough. I guess you have to decide if the price difference is so significant that you want to go with good enough.
Nina,
I've seen more failed CMU foundations than failed concrete foundations. In my opinion, you are more likely to see cracks or even bowed walls if the foundation is made of CMUs than if the foundation is made of poured concrete.
I wouldn't hesitate for a moment to pay an upcharge for a poured concrete foundation. I would choose poured concrete every time.
-- Martin Holladay
There is a saying: "A lawyer who represents himself has a fool for a client." I believe being an experienced project manager and acting as the general contractor of your own home is a lot like that. I know that sounds a little harsh, but here is my reasoning:
*A good builder / general contractor has long term relationships with subs and vendors. The subs and vendors know that he/she will use them again and again if they perform correctly. You will use those firms just once.
*Building a home means taking on a thousand decisions, every one time consuming. Let the general contractor figure out which nailing pattern to use, so you have time to pick the right lighting fixtures. (Let me tell you, there can be a fair amount of emotion involved with some of those aesthetic decisions.)
*General contractors handle issues of liability, worker's comp etc. And speaking of insurance issues, it will probably be easier to get builder's risk insurance for your home if you can write down one GC as prime. Similarly I think banks would prefer to see a home built by one GC.
Anyhow, I hired a GC for our home, even though I grew up around construction and in my career had managed many millions of dollars worth of complex commercial construction projects. I knew there were going to be things I didn't know. There were times during our project that turned out to be an understatement.
Now as to cement block versus solid concrete, I am surprised that no one has mentioned Superior Walls. Down here in Pennsylvania Superior Walls (and poured concrete) have decimated the block wall business; our local block plant even closed. I see there is a Superior Walls dealer up your way, might be worth looking into. http://www.superiorwallsnypa.com/
Lastly getting a good concrete guy, well we went through five different masons on our house as we handled different tasks. We (and that "we" is the GC and me) now have a great one. They are out there...
Andrew, Thank you for your response, and I will take it seriously. This has been a concern of ours from the beginning. Regarding superior wall, I am in contact with them. Our site is not the easiest to get to (over the river-creek really- and through the woods-approximately 300 feet or so up a hill) so what the bridge can handle dictates any decision. The gentleman from superior walls was suppose to come out to the site this week, but we are waist deep in snow at the moment, so his visit will probably have to wait until substantial snow melt.
I am a GC and agree with other posters that a GC brings value to the project, BUT, every year, thousands of "non builders" successfully build their own homes. Enjoy the journey!
As for CMU vs poured concrete: You do not mention if it is a crawl space, slab on grade or full basement? Assuming the foundation is on footers, I would not hesitate to use CMU for a crawl space or slab on grade. As for a full basement there are other questions: height of walls, lengths of walls,
soil type, height of backfill and access for concrete truck?
Richard, Thank you for the encouragement and words of caution.
It will be a full basement, current diagram elevation for the basement is 8'-10 1/4", length of walls: 32x40, soil type is Cazenovia silt loam, fill will be close to the 1st floor elevation grade except for the southeast corner where there will be a walkout, and there will be poured footers. Access is tricky, but there is a company that can pump up to 500 ft and we only need it go 300-350 if a truck cannot get over the bridge. Not sure that information would give you what you need for advice, but any you provide is appreciated.
Who is providing structural warranty to this project? Think about this carefully. Tract builders is the way go unless your budget is unlimited.
Nina:
I wonder if you've checked on the ability redo-mix cement truck to cross your bridge They do have long hoses and pumps for some applications (and sometimes much smaller trucks), but I'm sure that adds a great deal of expense. Cement block could be brought in several loads, but like Martin, I think a poured wall is preferable.
I don't mean to diss GC's or undervalue them, but as someone who built their own house and has maintained it for 40+ years, knowing much less than you seem to (at least early on before the internet and the likes of GBA and BSC were available), I think you could oversee things. If money is not much of a factor, I'm sure GC's are worthwhile. But you could perhaps even pay a GC or other trusted knowledgeable person for the right to pick his/her brain when needed (a consultant), which would not be all the time. You sound like someone who is thorough and knows how to gather the needed info, and I think could save yourself thousands of dollars and avoid the occasional but oft repeated horror stories.
Good question on the structural warranty. I do not have an answer, but will have to before we break ground. We are looking at concrete companies that have varied equipment and have asked that they conduct a site visit prior to giving a quote. We actually do have a consultant available to us. She started out in residential construction and now is a project manager for commercial projects. She stays busy, but is there for us when we need her. She set us off to research and educate ourselves on various aspects of the structure and to price out things that are reasonable at this stage. We just received preliminary plans on Friday, but have not sat down to speak to her, but am trying to anticipate some of the decisions that she is going to tell us we need to make; the big reason I subscribed to site. I do try to align myself with the those who have the expertise that I lack. Funny thing is that I retired from the military having had supervised GCs and building projects on the occasion, although this is nothing like that, I did learn a lot about managing sub contracting crews, but I did rely on the GC's technical experience heavily. Thank you for your comments.
Nina, one quick thing, check with your fire department on truck weight and access. That, and how your insurance company feels about same, may be informative.
BTW, our neighbor across the road had to build a new bridge across a creek in order to construct his home. In the end the bridge was big enough for concrete trucks, Superior Walls, etc deliveries, but he did have to go through some hassle with DEP to get the crossing location approved. (Which may be part of what you are trying to avoid.)
Andrew, The fire station did have to come out and verify that they could get their small truck across it. There is also the option of a temporary buttress during the construction period, but we would have to through the NY DEC, which the thought of makes my insides want to implode. It will cost more to get concrete and electric to the site, other services are not a problem. Just made contact with a concrete company, which has been told us by several builder to be the best in the area, not to mention our builder has worked with on several houses. Fitting them into the budget would really solve a lot, particular my concerns about concrete block.
I read a post today about supplies of pre used rigid foam in the Syracuse area, which is not far. Anyone have additional thoughts on using pre used, and what a person would look for?
Nina, your project management skills are definitely coming in handy; good that you have the fire department aspect covered
If you haven't done it already, I recommend you ask a separate question on Green Building Advisor about the pre-used / re-used foam. Think you will attract the right folks that way, and get great answers.
Oh and when you ask the question you might consider describing what the foam will be used for, is it going under your basement slab for example. And likely someone will also ask what kind of home you plan on building, what climate zone (I think the Finger Lakes covers two), etc
Thank you again Andrew; I really appreciate your feedback!!
FWIW my vote is for poured walls.
I've yet to see a block foundation in cny that doesn't have a at least one major crack, or need to be repointed. They may work in different climates but I wouldn't consider using one
Poured concrete walls for basements are far superior. A good block wall can work, but by the time you add the extra expenses of select granular backfill and more robust water proofing, you may as we'll go with a poured wall and get a stronger wall.