[DIYchick93]

Hello!

Thanks in advance for taking the time to read this. I'll try to keep it brief :wink2: My hubby and I own a 24 x 28 cabin in the mtns of northern Wyoming which needs lots of work. It's basically the shell of a tiny house right now. The original osb subfloor has extensive water damage. It will hold weight but is obviously warped and needs to go. It currently has a pier foundation under it consisting of pressure treated beams and basically concrete deck blocks. The crawl space is narrow, 12-14" , but I've managed to get under it and checked and the bottom looked in good shape. No visible termite, water, or rodent damage. My concern is that it's not just the subfloor thats warped. That maybe the blocks have settled over time or due to the frost(it gets down to -40 up in the mountains) and will worsen with added weight. Also the soil is dry and a mix of red clay and lava rock.

My question is this--- after I rip the floor up, would it be more prudent to dig and pour new concrete piers(mind you I'd have to dig past Wyoming's 60" frost line) OR should I reinforce and leave the old piers and maybe add concrete block and insulation to make a kind of shallow frost protected foundation of sorts ...???? Is mortar and block better than just plain block by itself? What would be the best option in the long run?

Any advice or recommendations are greatly appreciated!!!

 

[Marson]

Hello!

Thanks in advance for taking the time to read this. I'll try to keep it brief :wink2: My hubby and I own a 24 x 28 cabin in the mtns of northern Wyoming which needs lots of work. It's basically the shell of a tiny house right now. The original osb subfloor has extensive water damage. It will hold weight but is obviously warped and needs to go. It currently has a pier foundation under it consisting of pressure treated beams and basically concrete deck blocks. The crawl space is narrow, 12-14" , but I've managed to get under it and checked and the bottom looked in good shape. No visible termite, water, or rodent damage. My concern is that it's not just the subfloor thats warped. That maybe the blocks have settled over time or due to the frost(it gets down to -40 up in the mountains) and will worsen with added weight. Also the soil is dry and a mix of red clay and lava rock.

My question is this--- after I rip the floor up, would it be more prudent to dig and pour new concrete piers(mind you I'd have to dig past Wyoming's 60" frost line) OR should I reinforce and leave the old piers and maybe add concrete block and insulation to make a kind of shallow frost protected foundation of sorts ...???? Is mortar and block better than just plain block by itself? What would be the best option in the long run?

Any advice or recommendations are greatly appreciated!!!

Are there any other signs of major settling or movement? Do the doors/wiindows work. Major cracks or anything inside? Obviously, frost footings are ideal, but holy smokes is that a lot of back breaking work. So if you don't see a lot of evidence of settling/heaving, I'd question whether it would be worth it in the end. There are plenty of little cabins that aren't on real foundations. Now if you were going to add on to it, or add a story, or sink a pile of money into it, that would be a different thing.


Frost protected footings do work, but the rub is that you have to bury the foam, typically 4' out from each post. Doesn't work to just lay it on the ground.



If you really wanted to add a foundation, you could jack it up high enough so you could fit some equipment under there. Or do like a friend of mine did and build a foundation next to his little house on piers, and built ramps and used coffin hoists to winch the house onto the foundation.



Or you can do what I did with my little cabin. I poured 16" x 16" x 6" pads dug just below the organic layer and put blocks on them. This has worked well, though it a very forgiving site--a well drained gravel knoll. All me doors work, no cracks in the sheetrock, and it helps out my property taxes:smile:

 

[HotRodx10]

Are there any other signs of major settling or movement? Do the doors/wiindows work. Major cracks or anything inside?

Those are important questions, and I'll add one more that goes along with them. How long has it been on this foundation?


Frost heave doesn't cause settlement; actually, the opposite, but it requires the right conditions (moist to saturated soil) and the right soil type (clay or some organics), which are not common in northern Wyoming. Where, if I might ask, is it? I grew up in Lovell, and know the area fairly well.

 

[DIYchick93]

Are there any other signs of major settling or movement? Do the doors/wiindows work. Major cracks or anything inside? Obviously, frost footings are ideal, but holy smokes is that a lot of back breaking work. So if you don't see a lot of evidence of settling/heaving, I'd question whether it would be worth it in the end. There are plenty of little cabins that aren't on real foundations. Now if you were going to add on to it, or add a story, or sink a pile of money into it, that would be a different thing.


Frost protected footings do work, but the rub is that you have to bury the foam, typically 4' out from each post. Doesn't work to just lay it on the ground.



If you really wanted to add a foundation, you could jack it up high enough so you could fit some equipment under there. Or do like a friend of mine did and build a foundation next to his little house on piers, and built ramps and used coffin hoists to winch the house onto the foundation.



Or you can do what I did with my little cabin. I poured 16" x 16" x 6" pads dug just below the organic layer and put blocks on them. This has worked well, though it a very forgiving site--a well drained gravel knoll. All me doors work, no cracks in the sheetrock, and it helps out my property taxes:smile:

Thanks Marson,

There is some other evidence of shifting -- a few of the windows and a door are tricky to close, not impossible but noticeable. It's easy to see when you look at it that there was some settling. The cabin is 10 years old, which I believe is pretty young in house years so it s only going to worsen, right?

We were planning to eventually live out there so if I wasn't going to sink a ton of money into it then I wouldn't care so much lol.

 

[DIYchick93]

Those are important questions, and I'll add one more that goes along with them. How long has it been on this foundation?


Frost heave doesn't cause settlement; actually, the opposite, but it requires the right conditions (moist to saturated soil) and the right soil type (clay or some organics), which are not common in northern Wyoming. Where, if I might ask, is it? I grew up in Lovell, and know the area fairly well.

HotRodx10,

It's been on the pier foundation for 10 years. It's north of Gillette, nearly to the Montana border. The previous owner let the outside gutters go and I've witnessed rain pouring straight off the roof and pooling next to the house during a good storm. The soil has Bentonite in it, which, when wet, turns the earth into putty. It doesn't help either there's no good drainage or gravel. I plan on installing new gutters and a French drain to help with that.

 

[HotRodx10]

The soil has Bentonite in it, which, when wet, turns the earth into putty.

...slippery as all-get-out when it first gets wet, like glue after the water finally soaks in, and as hard as concrete after it dries. Lovely stuff, ain't it?

The cabin is 10 years old, which I believe is pretty young in house years so it s only going to worsen, right?

Not necessarily. Often the settling is worst in the first couple years, and decreases after that. It doesn't sound like the settlement thus far has been alot, so unless it's gotten noticeably worse in the last couple years, you've likely seen the worst of it, especially if you can successfully direct the water away from the piers.



You may just need to find the piers that have settled more and shim the beams on them up to bring those areas back in line. Pairs of shallow wedges of pressure treated lumber work well for that. Setting up a laser level with a sight line to the main beams could help determine where to shim, or methodical checking of the level on the floors inside may also direct you to the right areas.

It's north of Gillette, nearly to the Montana border.

Ah yeah, good ol' Highway 59. We had so much fun trying to fix the culverts under that road about 12 years ago. We had one so silted in we had trouble finding it - a 7' tall concrete box culvert where all that was visible was about 6" of the 18" tall parapet above the opening (yeah, the gully had silted in 8' over the last 40 years). A few miles up the road, the water had flowed through another box the same size so fast it had worn a 1/2" on concrete off the bottom slab and eroded out a swimming pool at the outlet. Fun times! Very pretty area, though.

 

[Nealtw]

Hello!

Thanks in advance for taking the time to read this. I'll try to keep it brief :wink2: My hubby and I own a 24 x 28 cabin in the mtns of northern Wyoming which needs lots of work. It's basically the shell of a tiny house right now. The original osb subfloor has extensive water damage. It will hold weight but is obviously warped and needs to go. It currently has a pier foundation under it consisting of pressure treated beams and basically concrete deck blocks. The crawl space is narrow, 12-14" , but I've managed to get under it and checked and the bottom looked in good shape. No visible termite, water, or rodent damage. My concern is that it's not just the subfloor thats warped. That maybe the blocks have settled over time or due to the frost(it gets down to -40 up in the mountains) and will worsen with added weight. Also the soil is dry and a mix of red clay and lava rock.

My question is this--- after I rip the floor up, would it be more prudent to dig and pour new concrete piers(mind you I'd have to dig past Wyoming's 60" frost line) OR should I reinforce and leave the old piers and maybe add concrete block and insulation to make a kind of shallow frost protected foundation of sorts ...???? Is mortar and block better than just plain block by itself? What would be the best option in the long run?

Any advice or recommendations are greatly appreciated!!!

Sounds more like out of level that rot.

Did you build this treasure? Do you know if the top soil was removed to put the blocks down or were they just levelled up and built on.

When you get frost heave it may or likely won't go back in place in the spring or you could just have settling.


Digging post holes under the center of a house is not fun. But people have tunnelled out prison camp so how bad can it be?:biggrin2:

 

[DIYchick93]

...slippery as all-get-out when it first gets wet, like glue after the water finally soaks in, and as hard as concrete after it dries. Lovely stuff, ain't it?


Not necessarily. Often the settling is worst in the first couple years, and decreases after that. It doesn't sound like the settlement thus far has been alot, so unless it's gotten noticeably worse in the last couple years, you've likely seen the worst of it, especially if you can successfully direct the water away from the piers.



You may just need to find the piers that have settled more and shim the beams on them up to bring those areas back in line. Pairs of shallow wedges of pressure treated lumber work well for that. Setting up a laser level with a sight line to the main beams could help determine where to shim, or methodical checking of the level on the floors inside may also direct you to the right areas.]

You hit the nail on the head! lol It's a pain in the butt.

Ok, good to know. That makes sense as most of the water damage occurred the first year....or so I've heard 'through the grapevine'. The original owner built the foundation...was lazy and left it to get rained on for a month or so before finishing the walls and ceiling. Smh. Then to hide the warping in the floor he screws 2 x 4 x 10s down, further compromising the osb. They were crooked as anything and took me a good couple days to rip up!


I like your idea about the shims and laser level, I was thinking along those lines.

 

[DIYchick93]

Sounds more like out of level that rot.

Did you build this treasure? Do you know if the top soil was removed to put the blocks down or were they just levelled up and built on.

When you get frost heave it may or likely won't go back in place in the spring or you could just have settling.


Digging post holes under the center of a house is not fun. But people have tunnelled out prison camp so how bad can it be?:biggrin2:

Nope not me, lol. Believe me some days I think about just starting from scratch but I can't afford that.

The original owner, genius that he was, smh, built the foundation and floor. Then left it to get rained on for a month before finishing the walls and roof....or so I've heard from the neighbors. There's slim to none top soil in this location so I'm pretty sure they just leveled it. The sub-floor is warped permanently...I've seen it in winter and summer and its the same. The door and windows do seem to get a bit stickier in the spring months.

I'd definitely prefer not to dig the post holes but hey I'm stubborn as a mule once I get started on a project(ask my husband) lol so if it comes to that I will.:biggrin2:

 

[HotRodx10]

The door and windows do seem to get a bit stickier in the spring months.

Most likely an effect of the bentonite clay getting wet. If you're successful in diverting the runoff/snowmelt away from the cabin, that shouldn't continue to be a problem.

 

[Nealtw]

Nope not me, lol. Believe me some days I think about just starting from scratch but I can't afford that.

The original owner, genius that he was, smh, built the foundation and floor. Then left it to get rained on for a month before finishing the walls and roof....or so I've heard from the neighbors. There's slim to none top soil in this location so I'm pretty sure they just leveled it. The sub-floor is warped permanently...I've seen it in winter and summer and its the same. The door and windows do seem to get a bit stickier in the spring months.

I'd definitely prefer not to dig the post holes but hey I'm stubborn as a mule once I get started on a project(ask my husband) lol so if it comes to that I will.:biggrin2:

How high off the ground is it, Working space?

Best is to level it first before working on the floor and monitor it for a year

before further changes to the piers.

You might have sagging joists or other fixable problems

I don't suppose you know what size the joists are and the span.

 

[DIYchick93]

How high off the ground is it, Working space?

Best is to level it first before working on the floor and monitor it for a year

before further changes to the piers.

You might have sagging joists or other fixable problems

I don't suppose you know what size the joists are and the span.

Not a lot. There's just enough space in the back for a little person like me to bellycrawl under(I'm 5'4"), then it narrows to a couple inches towards the front. That's why I'm thinkin ripping up the floor will be another perk.

No sorry I don't know without measuring em. It's a possibility, but I don't think so. I'd have to get a level on them to be 100% sure. Oddly enough tho to the naked eye, they look razor straight compared to the floor. Definitely planning on reinforcing the crap outta the joists, either way. :wink2:

 

[Nealtw]

Not a lot. There's just enough space in the back for a little person like me to bellycrawl under(I'm 5'4"), then it narrows to a couple inches towards the front. That's why I'm thinkin ripping up the floor will be another perk.

No sorry I don't know without measuring em. It's a possibility, but I don't think so. I'd have to get a level on them to be 100% sure. Oddly enough tho to the naked eye, they look razor straight compared to the floor. Definitely planning on reinforcing the crap outta the joists, either way. :wink2:

So just to level it you would have to remove some floor to get to piers in the middle of the house anyway.



So you will need a stationary laser level so you can map the floor.
Easiest to do from below but you will have to do it from inside.

 

[Nealtw]

Not a lot. There's just enough space in the back for a little person like me to bellycrawl under(I'm 5'4"), then it narrows to a couple inches towards the front. That's why I'm thinkin ripping up the floor will be another perk.

No sorry I don't know without measuring em. It's a possibility, but I don't think so. I'd have to get a level on them to be 100% sure. Oddly enough tho to the naked eye, they look razor straight compared to the floor. Definitely planning on reinforcing the crap outta the joists, either way. :wink2:

Do you know how many rows of piers are in the center of the house.
Lots of people just put them every 6 or 8 ft apart with out thinking about where the load bearing walls are and that is a recipe for a wavy floor.