bill1952
SAWHORSE
I noted in first post that this was a post frame/pole barn. I learned post frame is not subject to the prescriptive requirements of the IRC. It's an IBC type U building.
Moisture meaning adsorbed water instead of free water. You assume incorrectly. You can try to talk down to someone else; discuss phase of water all you want in building science but this is a geotechnical issue, not vapor drive. In geotechnical engineering there is certainly a difference between bulk water and moisture. But, hey, thanks for a bunch of information from 6th grade science completely irrelevant to frost heave. You have a building science hammer so it must apply to a geotechnical nail!!!What "moisture" are you seeing that is not water?
Water is all H2O, regardless of phase. In the world of building science, if we want to talk about a specific phase of water we say phase [vapour/liquid/ice] water. We rarely refer to moisture as it means either vapour or small amount of condensation.
With this in mind, I assume you are indicating that there would be phase vapour water contained in the soil that can cause frost, I would question how often this happens. Typically, there will be an intermediate phase change to phase liquid water before the ultimate phase change to phase ice water. There are conditions that can be present that causes deposition where phase vapour water undergoes a phase change directly to phase ice water, but the conditions are extremely demanding for this to be able to happen naturally.
The capillary force holding water is not just present in clay, but any soil particles small enough to ensure the adhesion of the water molecules to the soil particles overlaps sufficiently to defeat gravity.
You're probably right. I don't know nearly enough about geotechincal engineering to be considered an expert. I'm sorry you misunderstood what I was referring to in my original post. I was referring to water as being the molecule and assumed most would come to the conclusion I would be talking about water absorbed into the soil since trying to place a concrete slab over a body of open water (bulk water as you put it), doesn't sound like your typical residential garage. I'm glad we were able to clear up the miscommunication.Moisture meaning adsorbed water instead of free water. You assume incorrectly. You can try to talk down to someone else; discuss phase of water all you want in building science but this is a geotechnical issue, not vapor drive. In geotechnical engineering there is certainly a difference between bulk water and moisture. But, hey, thanks for a bunch of information from 6th grade science completely irrelevant to frost heave. You have a building science hammer so it must apply to a geotechnical nail!!!
Capillary force is present in all fluid/solid interactions. But clays are different from granulars. The quick and easy answer is the size and shape of the particles. Clays particles are flat like a playing card and stack closely. Frost heave occurs when adsorbed water between the playing cards freezes and creates a frost lens driving the particles apart. Granular soils have relatively enormous spaces between particles which allow free draining of water and also allow the frost somewhere it can expand (kinda like air entrainment). It does get much more complex, see your local geoengineering professor for a more detailed answer. Try not to mansplain to them, they, understandably, don't like that much.
No one has mentioned water table depth or perculation of soil yet.Moisture meaning adsorbed water instead of free water. You assume incorrectly. You can try to talk down to someone else; discuss phase of water all you want in building science but this is a geotechnical issue, not vapor drive. In geotechnical engineering there is certainly a difference between bulk water and moisture. But, hey, thanks for a bunch of information from 6th grade science completely irrelevant to frost heave. You have a building science hammer so it must apply to a geotechnical nail!!!
Capillary force is present in all fluid/solid interactions. But clays are different from granulars. The quick and easy answer is the size and shape of the particles. Clays particles are flat like a playing card and stack closely. Frost heave occurs when adsorbed water between the playing cards freezes and creates a frost lens driving the particles apart. Granular soils have relatively enormous spaces between particles which allow free draining of water and also allow the frost somewhere it can expand (kinda like air entrainment). It does get much more complex, see your local geoengineering professor for a more detailed answer. Try not to mansplain to them, they, understandably, don't like that much.
? if the ground is frozen how will it percolate?perculation of soil yet.
Frozen soil can support a slab. How do you frost protect a slab in an unheated space??I've been called thick and dense on this, which if I were a building material could be a compliment, but so frustrating that both the local building official and a fairly experienced RDP (architect) matter of factly state the IRC requires a slab in a post frame building - a floating slab or unrestrained slab or no-foundation slab as you choose - to be frost protected. This is 2020 NY residential code, based on 2018 IRC, but I did not see any differences.
Now, if it were a bona fide agricultural building, no permit and no frost protection, but I'm not able to come close to that claim.
Just frustrating that the code is not clear and by that I mean:
"R301.1Application.
Buildings and structures, and parts thereof, shall be constructed to safely support all loads, including dead loads, live loads, roof loads, flood loads, snow loads, wind loads and seismic loads as prescribed by this code. The construction of buildings and structures in accordance with the provisions of this code shall result in a system that provides a complete load path that meets the requirements for the transfer of loads from their point of origin through the load-resisting elements to the foundation." but many say a garage floor is not a part of the building and structure and that the code required live and dead loads of garage floors are excluded from this. Perhaps buildings and structures don't include some floors but no one has pointed out that section which says some are and some are not (albeit all floors in under 600 sq ft buildings are excepted - not what we are talking about). I accept it's fine and is not a safety and welfare issue. If the only response is the building official, the architect, and I are dense and thick, don't bother responding.
Just to be clear, this is not a code requirement, correct? It seems everyone is saying it's ok and permitted by the IRC for a floor slab on ground or on grade to heave.In an unheated building the soils below the concrete slab can freeze and lead to frost heave and broken concrete. Insulation below the slab will prevent the soils below the insulation from freezing
THREE WAYS OF PREVENTING FROST HEAVE
Because of heat loss to the surrounding soil, heated buildings rarely suffer frost heave damage. Frost heave also is avoided by extending footings below the frost line. Pavements, driveways, sidewalks, and floor slabs of unheated buildings are not supported by footings, however. To protect these structures, you must eliminate or minimize at least one of the three conditions that lead to frost heave: reduce frost penetration; keep water out of the freezing zone; or make sure soil in the freezing zone is not susceptible to frost.
Point the to the millions of garages (literally) with floating slabs that are not frost protected whatsoever. There is a very clear, direct load path for slabs on grade (hint: it's right in the name).Just to be clear, this is not a code requirement, correct? It seems everyone is saying it's ok and permitted by the IRC for a floor slab on ground or on grade to heave.