FPSF Quandary in NY
We are hoping to apply for a permit in two weeks for our 1200 square-foot home here in zone six (upstate New York). We’d like to start excavating for the foundation on May 1. The bank is already broken, so to speak, but we are attempting to have the funds to build a pretty good house, with vapor open R 40 walls, and a vapor open R 60 roof.
At the 11th hour, our architect has said he all but refuses to draw a frostproof shallow foundation, which is what we have been hoping to do all along, and we have found a mason who is willing to learn about and pour it. New York building codes are certainly stringent (and require an architect or engineer to sign off on stamped plans), but it is my understanding that frostproof shallow foundations are up to code in all states, and I would love a sanity check…someone who might be able to help me help our Architect feel comfortable with the concept of a FPSF…and/or any recommendations for NY licensed architects or engineers who would miraculously have some time this month to stamp our drawings after adding a frostproof shallow foundation…
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Replies
What’s the purpose of a shallow foundation in your proposed build?
I have always sung the praises of full basements, especially in the north. The additional cost (over a crawl) is not significant in the bigger picture.
Well, mainly because we aren't going to get a basement or a crawlspace for $32K, and we are hoping to put the tiny bit of money we will have left after the foundation into insulation, even though the builder tells us that R40 walls may just not be possible with our budget...
There is nothing wrong with the traditional approach to the foundation and slab.
The only benefit I see with a FPSF is that it eliminates a couple steps and harmonies some of the proces. This is useful for someone like me l because I do all the building myself. I've done it on a smaller slab, and I enjoy them.
However, If I wanted to hire a concrete sub and they had zero experience and are otherwise unwilling, I wouldn't try to force it upon them. Mostly because that means they'll charge more for the higher risk their taking and have a higher chance of screwing up a detail.
Everything is great in theory, but when it comes time to find or engage humans to execute, nothing is perfect. We tend to mess things up. Working as a team is our singlehanded greatest skill as a species, but there are still varying degrees of it in today's age.
So take my personal experience with a grain a salt as I'm just some guy on the internet:
You could still do a 'regular' slab on grade that is just as perfomant. If the engineer and the foundation team is comfortable with that, that's probably your best bet to get it done.
If at the 11th hour you manage to find another eng and a foundation team that are comfortable with it and charge the same price and are just as available. That works to.
The only difference is the sequencing of work for the foundation team. The end result would be the same.
Hope this helps,
Jamie
There are many great reasons to use a FSPS instead of more traditional (and expensive, and carbon-intensive) foundations and they have proved to be effective in all states for over 50 years. They don't work on every site; if you are on a hillside or have expansive clay there may be better options.
ASCE 32-01 is the document licensed engineers are supposed to follow if the IRC prescriptive codes aren't sufficient.
There is also this resource, which has been popular since it came out 30 years ago: https://www.huduser.gov/portal/publications/destech/desguide.html.