rogerthat
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Icf’s dude
Any builders here? Foundation advice
- Thread starter Jonesy125
- Start date
BigHornRam
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He's from the south, where it doesn't get cold.
Brittany Chukarman
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Do you have to backfill to achieve frost line requirements or are you below frost line as it is?
BigHornRam
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Good luck with your cabin project, and hope it all goes smoothly. Let's see some pics when you get it done.
BigHornRam
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Frost depth in Montana is 32" to 48" depending on where you are building.
Yea I do bottom of footings will end up 46” below grade
trackerbacker
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Don't worry about bracing when backfilling. Just don't ram shit or compact it what the equipment. Rough grade it out at best, let it compact and fracture until the spring. Once you're done framing, run a soaker house around to further settle, then fill as needed.
Haven't looked at the specs of that ICF product, get some 15 year tar on it.
Have any water seams running near? Any water seep up through the hole currently?
If you bed it, grab some buddies or family, have a baling party in the spring. put food and drink into people romantically for the help. Any sitting water, grab a sump pump or other pump and pump her out.
Eta- since I'm guessing you're framing the floor system conventionally, and no beam pockets, I'm guessing you're recessing the beam and running joists into it? Or is the plan to post the beams? Don't forget pads for the posts if/ when you pour, should've been done at ftgs, but not a prerequisite at that point.
Post up some BPs, not for critics but since you said diy, more eyes never hurt.
Haven't looked at the specs of that ICF product, get some 15 year tar on it.
Have any water seams running near? Any water seep up through the hole currently?
If you bed it, grab some buddies or family, have a baling party in the spring. put food and drink into people romantically for the help. Any sitting water, grab a sump pump or other pump and pump her out.
Eta- since I'm guessing you're framing the floor system conventionally, and no beam pockets, I'm guessing you're recessing the beam and running joists into it? Or is the plan to post the beams? Don't forget pads for the posts if/ when you pour, should've been done at ftgs, but not a prerequisite at that point.
Post up some BPs, not for critics but since you said diy, more eyes never hurt.
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No water seems or seeping. Beams will be posted and pads have been poured with footing. I have bps on my work computer can post up pictures next week. Pretty simple design, fairly open with 2 bedrooms and a bath. Haven’t decided for sure on roof design I want traditional gable she wants single slope. I think
Mostly so we would have extra wall height and I could get the euros out of our house lol.
Thanks, should be plenty of rebar in there walls have rebar ran every foot horizontally and vertically.
BigHornRam
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That is plenty plus some!
Nick87
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I'm not saying it's right but usually less than 4 days and they've got us backfilling.
Bambistew
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TLDR - backfill and call it good. Soils look like gravels and well draining. Your actual frost penetration is likely higher than your foundation depth already.
From a geotechnical/engineering standpoint, and based on 20+ years of working on foundations, soil mechanics, etc in the north and arctic regions...Not all soils will heave, some move way more than others, some will not move at all. Fore example most roadways if properly designed will not move much, if at all, in the winter. You need 3 things to heave, freezing conditions, moisture and fine content >5% passing the 200 sieve. You'll see some minimal movement between 5-8%, and it goes up from there. The amount of fines dictates the amount of moisture the soil can hold, unless you have a high water table, which in that case, you can draw moisture from the ground upwards, which really makes things move.
Unless you are heating the cabin year round, you will have freezing conditions in your foundation/footers in the winter, foam or not on the walls. Well drained soils have a higher depth of frost penetration. Note that frost penetration's is dependent upon insulating snow layer and soil moisture. Under your eve, you'll have little to no snow accumulation, and if you have a porch/deck out front, it will also be snow free. You will get higher than normal frost penetration along the foundation walls. In areas with high moisture content you could have as little as 1-2 feet of frost penetration, in areas with well draining soils, you could have 6-10 ft. We get over 10ft of frost penetration in our roadways here in Anchorage, for example. In areas under snow I've seen as little as 16" to the frost line in soils with high moisture content (swampy forested terrain). It takes a lot of energy to freeze water.
Personally, I'd backfill it and call it good once the concrete is cured. No real reason to compact the soils other than to reduce subsidence next to the building. I've seen many foundations left over the winter with no ill effect. Insulating wing walls (perpendicular to the foundation walls) isn't a bad idea, but not really necessary in footer/wall foundations, more so for SOG type designs.
One last note. Typical "builder" type foundation designs for buildings are quite over designed for actual conditions and also assume some average frost depth. This simplifies actual design and engineering and the final "rule of thumb" type designs work 95% of the time without any other consideration.
From a geotechnical/engineering standpoint, and based on 20+ years of working on foundations, soil mechanics, etc in the north and arctic regions...Not all soils will heave, some move way more than others, some will not move at all. Fore example most roadways if properly designed will not move much, if at all, in the winter. You need 3 things to heave, freezing conditions, moisture and fine content >5% passing the 200 sieve. You'll see some minimal movement between 5-8%, and it goes up from there. The amount of fines dictates the amount of moisture the soil can hold, unless you have a high water table, which in that case, you can draw moisture from the ground upwards, which really makes things move.
Unless you are heating the cabin year round, you will have freezing conditions in your foundation/footers in the winter, foam or not on the walls. Well drained soils have a higher depth of frost penetration. Note that frost penetration's is dependent upon insulating snow layer and soil moisture. Under your eve, you'll have little to no snow accumulation, and if you have a porch/deck out front, it will also be snow free. You will get higher than normal frost penetration along the foundation walls. In areas with high moisture content you could have as little as 1-2 feet of frost penetration, in areas with well draining soils, you could have 6-10 ft. We get over 10ft of frost penetration in our roadways here in Anchorage, for example. In areas under snow I've seen as little as 16" to the frost line in soils with high moisture content (swampy forested terrain). It takes a lot of energy to freeze water.
Personally, I'd backfill it and call it good once the concrete is cured. No real reason to compact the soils other than to reduce subsidence next to the building. I've seen many foundations left over the winter with no ill effect. Insulating wing walls (perpendicular to the foundation walls) isn't a bad idea, but not really necessary in footer/wall foundations, more so for SOG type designs.
One last note. Typical "builder" type foundation designs for buildings are quite over designed for actual conditions and also assume some average frost depth. This simplifies actual design and engineering and the final "rule of thumb" type designs work 95% of the time without any other consideration.
trackerbacker
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Well folks, and I do not mean this insultingly, believe you me, Dr Dirt hath spoken.
One of my Geotech subs, who I respect immensely, has said things very similarly at multiple projects relative to the scope you have, though similar and different topics.
I'd bend your ear on random crap any day.
trackerbacker
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Know the feelings on "he said she said" house design.....
Good luck and looking forward to your project.
On a 4' wall it absolutely doesn't matter. Backfill away after letting the walls cure at least a week. Straw, etc., on the interior not needed.
Thanks to everyone who gave advice on this. You eased my mind over the winter and also didn’t f*ck up hunting season. Should be wrapped up for the year by tomorrow evening . So I have a full 7 days to get myself and the llamas in shape before elk season!!!
The footings will be below frost line, i just can’t get dried in this year so the crawl space area is exposed to frost/ outside conditions.
You’re absolutely fine - no need to worry.
