# What’s the most affordable small house foundation



## Kevo (Mar 28, 2012)

Hey folks.

I am building a small house 24’x40’. Will be metal roof, single story and would prefer clear span. I live in north Alabama. No restrictions at all. Building without a mortgage but can borrow about $5000 at a time unsecured along with cash flow. what kind of foundation would you recommend. I have considered 6x6 treated posts concreted in the ground with 3 2x12s on top as beam. Every 8’ on piers. Any suggestions? I’m a little nervous because some folks online have reported rot after 10-15 years when treated posts are concreted in ground.


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## robin416 (Dec 29, 2019)

True that on the buried treated wood. Heck, I've got treated wood that is part of my breezeway and it hasn't been installed for longer than 20 years, per the old owner, and it's all rotted out. 

My suggestion is not to go cheap when it comes to your foundation. Use concrete block piers on footers. Or pour a slab. I'm in a slab now and can say I don't care for it. More complicated to work on plumbing or electrical. Bugs seem to like visiting me in the house more. And it's cold even down here in S. AL.


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## The Paw (May 19, 2006)

I can't speak to cost, but I would be looking at pouring concrete into those sonotubes.
https://www.sonotube.com/resources/faq.aspx
That would avoid any wood rot issues, and give you a crawl space that is preferable to a slab on grade IMHO.


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## Bearfootfarm (Jul 13, 2006)

Kevo said:


> I have considered 6x6 treated posts concreted in the ground with 3 2x12s on top as beam.


I'd use Sonotubes to pour concrete piers and use 2 2 x 10's for the bands and 2 x 8's for the floor joists

https://www.sonotube.com/sonotubeconcreteforms/round.aspx

https://www.bing.com/videos/search?q=Sonotubes&FORM=VQFRAF


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## ycanchu2 (Oct 21, 2011)

I am in the process of building an ICF home about that size Did a monolithic pour....footer and slab. I probably wouldn't do posts in concrete. I don't even like fence posts in concrete. You could put them in with gravel. Put a few inches in the bottom of the hole and then around it.


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## Lisa in WA (Oct 11, 2004)

Bearfootfarm said:


> I'd use Sonotubes to pour concrete piers and use 2 2 x 10's for the bands and 2 x 8's for the floor joists
> 
> https://www.sonotube.com/sonotubeconcreteforms/round.aspx
> 
> https://www.bing.com/videos/search?q=Sonotubes&FORM=VQFRAF


That is what we did.


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## AmericanStand (Jul 29, 2014)

I’d be inclined to dig down a few feet put in a footer and then pour a concrete slab on one side of the footer and a stub wall in the middle. 
The least expensive way is probably a flat slab on grade. 
In Alaska when they do that they pour it on top of a few inches of foam insulation to keep from having a cold floor


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## Bearfootfarm (Jul 13, 2006)

Lisa in WA said:


> That is what we did.


It's quick, easy and lasts forever.


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## Lisa in WA (Oct 11, 2004)

Bearfootfarm said:


> It's quick, easy and lasts forever.


Yep.


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## Fishindude (May 19, 2015)

I'd do a traditional concrete block or poured perimeter wall a top a strip footing, which would allow you to have a crawl space for mechanical runs, etc. 

A cheaper solution would be a slab on grade, with the outside edges of slab turned down a couple feet to serve as a perimeter footing.

I wouldn't build on posts and piers unless there was some reason I had to.


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## Bearfootfarm (Jul 13, 2006)

Fishindude said:


> I wouldn't build on posts and piers unless there was some reason I had to.


The OP title said "most affordable foundation".
Poured footings and block walls are better than piers, but cost a lot more and require more skilled labor.


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## painterswife (Jun 7, 2004)

I would do footers and stem walls.

Affordable does not just mean the intial costs. Having a crawl space makes all the plumbing and electrical easier and also makes future repairs or additions easier and more affordable.

It also keeps critters away from your plumbing and wiring.


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## robin416 (Dec 29, 2019)

Bearfootfarm said:


> The OP title said "most affordable foundation".
> Poured footings and block walls are better than piers, but cost a lot more and require more skilled labor.


Build a house on a weak foundation will be very expensive in the long run. 

There is the sugar high of thinking it was done on the cheap until it begins to fail. He has the money available to him to do a proper foundation so going cheap doesn't make sense.


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## Lisa in WA (Oct 11, 2004)

Bearfootfarm said:


> The OP title said "most affordable foundation".
> Poured footings and block walls are better than piers, but cost a lot more and require more skilled labor.


Yup. And our little cabin in northern Idaho is still standing strong on its piers almost twenty years later. Never had a frozen pipe or chewed wire.


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## ycanchu2 (Oct 21, 2011)

Put all your plumbing and electric in conduit in a slab. I used flexible electrical conduit to run pex thru.....easier to make sharper turns.


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## robin416 (Dec 29, 2019)

Except for my drain lines all of my plumbing and electrical is overhead.


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## painterswife (Jun 7, 2004)

robin416 said:


> Except for my drain lines all of my plumbing and electrical is overhead.


We have all vaulted ceilings. No attic and the roof is Structural insulated panels so the wiring needed to go through the crawl space in most instances.


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## robin416 (Dec 29, 2019)

My other house had vaulted, was built on a raised foundation where everything was under the house. This one everything is in the ceiling except the drains. 

I would not have to deal with everything in a slab. Conduit or not.


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## Bearfootfarm (Jul 13, 2006)

robin416 said:


> Build a house on a weak foundation will be very expensive in the long run.


There's nothing "weak" about concrete piers.



robin416 said:


> There is the sugar high of thinking it was done on the cheap until it begins to fail. He has the money available to him to do a proper foundation so going cheap doesn't make sense.


He asked for "most affordable".
That's not the same as what your use of "cheap" implies


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## Bearfootfarm (Jul 13, 2006)

painterswife said:


> Having a crawl space makes all the plumbing and electrical easier and also makes future repairs or additions easier and more affordable.


You can crawl under a house on piers also.
It has no effect on any of the things you've mentioned.


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## painterswife (Jun 7, 2004)

Bearfootfarm said:


> You can crawl under a house on piers also.
> It has no effect on any of the things you've mentioned.


You sure can crawl under it. The problem is you have to run all the wires and plumbing in the floors before you seal it off. With a crawl space you can build the entire building and the do the wiring and plumbing as cash allows. You also have less holes through the floor that allow mice, snakes and bugs in.


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## robin416 (Dec 29, 2019)

Bearfootfarm said:


> There's nothing "weak" about concrete piers.
> 
> 
> He asked for "most affordable".
> That's not the same as what your use of "cheap" implies


I meant his use of pressure treated wood for piers because that's kind of the way you worded it. 

But I've been known to misinterpret the typed word in the past.


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## Bearfootfarm (Jul 13, 2006)

robin416 said:


> I meant his use of pressure treated wood for piers because that's kind of the way you worded it.
> 
> But I've been known to misinterpret the typed word in the past.


No, that's not how I worded it at all.




Bearfootfarm said:


> I'd use Sonotubes to pour *concrete* piers and use 2 2 x 10's for the bands and 2 x 8's for the floor joists


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## Bearfootfarm (Jul 13, 2006)

painterswife said:


> You sure can crawl under it. The problem is you have to run all the wires and plumbing in the floors before you seal it off.


No you don't. 
Nothing is "in the floors".
I'm not going to play your silly game tonight.


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## painterswife (Jun 7, 2004)

Bearfootfarm said:


> No you don't.
> Nothing is "in the floors".
> I'm not going to play your silly game tonight.


How do you plumb a toilet or tub without putting it in the floor?


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## Bearfootfarm (Jul 13, 2006)

painterswife said:


> How do you plumb a toilet or tub without putting it in the floor?


I'm not going to play your silly game tonight.


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## painterswife (Jun 7, 2004)

Bearfootfarm said:


> I'm not going to play your silly game tonight.


Is that because you realized you are wrong and you can't plumb drains without putting them in the floor? I can understand that you might not want to admit your mistake on that.


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## Bearfootfarm (Jul 13, 2006)

painterswife said:


> Is that because you realized you are wrong


No, it's because it has nothing at all to do with the OP, and you don't seem to realize nothing you've said so far is factual.

You just want to argue like every other day, and I'm not playing the mindless back and forth with you tonight.


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## painterswife (Jun 7, 2004)

Bearfootfarm said:


> No, it's because it has nothing at all to do with the OP, and you don't seem to realize nothing you've said so far is factual.
> 
> You just want to argue like every other day, and I'm not playing the mindless back and forth with you tonight.


Please tell me how they would plumb drains without going in or through the floor. If I am wrong then you can easily provide the facts to prove it.


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## Lisa in WA (Oct 11, 2004)

Bearfootfarm said:


> No, it's because it has nothing at all to do with the OP, and you don't seem to realize nothing you've said so far is factual.
> 
> You just want to argue like every other day, and I'm not playing the mindless back and forth with you tonight.


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## Bearfootfarm (Jul 13, 2006)

Lisa in WA said:


>


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## Kevo (Mar 28, 2012)

Bearfootfarm said:


> I'd use Sonotubes to pour concrete piers and use 2 2 x 10's for the bands and 2 x 8's for the floor joists
> 
> https://www.sonotube.com/sonotubeconcreteforms/round.aspx
> 
> https://www.bing.com/videos/search?q=Sonotubes&FORM=VQFRAF


Just curious. How big is your house? How tall did you pour sonotube above grade? Did you use a connector and go straight to your girders/beams or did you have wood post up from sonotube to beam? Thanks!


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## Bearfootfarm (Jul 13, 2006)

Kevo said:


> How big is your house? How tall did you pour sonotube above grade?


My house was built on brick piers long before anyone thought of Sonotubes.

The ideal way to do them is have them as high above grade as it takes to give good ground 
clearance and adequate crawl space, and to set your beams directly on top with an anchor bolt coming up through the center. 

Use metal flashing between the concrete and the wood and let it overhang the piers by a couple of inches on all sides.


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## Bearfootfarm (Jul 13, 2006)

painterswife said:


> Please tell me how they would plumb drains without going in or through the floor. If I am wrong then you can easily provide the facts to prove it.


Unless the house is on a slab, there is nothing about the type of foundation that changes the way the plumbing or electrical is done. 



painterswife said:


> The problem is you have to run all the wires and plumbing in the floors *before you seal it off*.


What makes you think it's going to be "sealed off"?
Is your crawl space "sealed off", or is there still access?

The wiring and plumbing is mostly under the floor joists or in the walls. Any holes that need to be cut can be cut any time after the house is "dried in".



painterswife said:


> *You also have less holes* through the floor that allow mice, snakes and bugs in.


The type of foundation changes nothing about the number of holes needed for anything related to plumbing and electrical.

If your access holes are letting vermin in, your technique is sloppy or your bits are too big.


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## Fishindude (May 19, 2015)

For those with experience building on piers. Do you leave it open underneath or do you install some type of "skirting" around the perimeter to keep the weather and critters out?


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## robin416 (Dec 29, 2019)

Fishindude said:


> For those with experience building on piers. Do you leave it open underneath or do you install some type of "skirting" around the perimeter to keep the weather and critters out?


Block walls in GA.


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## painterswife (Jun 7, 2004)

Fishindude said:


> For those with experience building on piers. Do you leave it open underneath or do you install some type of "skirting" around the perimeter to keep the weather and critters out?


We have one building on piers. It was built and then moved on. It has just electrical. The bottom was built covered. Plywood first, then joists. Insulated and then the floor. No skirting. It has nothing going through the bottom.


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## Bearfootfarm (Jul 13, 2006)

> Fishindude said: ↑
> For those with experience building on piers. Do you leave it open underneath or do you install some type of "skirting" around the perimeter to keep the weather and critters out?


They are usually enclosed by some means now but in the past it wasn't unusual to leave them open.


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## Sebastian C (Jul 23, 2017)

TheMost inexpensive foundation is piers or sonotubes or whatever to put your posts r beams on. However, when you pour a slab foundation you have the cheapest easiest most durable subfloor or even final floor depending on how fancy you do it or want it. The only utility you NEED to worry about beforehand is the toilet tube, everything else can be done afterwards with conduit or running pipes through your cabinets or around the outside of the house.

But I like poured slabs because all flooring options get expensive pretty fast and wood is prone to bugs. If you can raise the walls up a little on block or piers too it's better to keep the bugs out it's better but more expensive obviously. We frame with metal a lot round here cuz wood is very expensive.
Under no circumstances is it a good idea to put any wood, treated or not, in concrete underground. Doesn't matter if you saw someone else do it.

Just my experiences and opinions.


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## fishhead (Jul 19, 2006)

I haven't priced Sonotubes so I don't know how much money could be saved but carpet layers pay to disposes of large cardboard tubes that might substitute for the other tubes.


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## IMFoghorn (Jan 28, 2012)

fishhead said:


> I haven't priced Sonotubes so I don't know how much money could be saved but carpet layers pay to disposes of large cardboard tubes that might substitute for the other tubes.


I've cut those tubes used to roll carpet to the proper length to use as concrete forms on a couple of occasions with good results. I flare out the bottom of the dug hole to enlarge the weight bearing surface.

JMO
Doug


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## Kevo (Mar 28, 2012)

fishhead said:


> I haven't priced Sonotubes so I don't know how much money could be saved but carpet layers pay to disposes of large cardboard tubes that might substitute for the other tubes.


Unfortunately, I believe cardboard tubes that carpet come on, have a small diameter. The quikrete tubes at Lowes are $15 for a 12" diameter x 48" long tube. 
I would think you could use the hole itself as part of the form. - My thought was to dig a 12" diameter hole 2 1/2' deep and try to "flare out the bottom foot as best I can, fill 6" gravel, then place and secure form tube about 6" in the hole and 18" above grade. That way I could use 1 tube for every 2 piers. 24 piers = 12 Tubes = $180
Still in the figuring it out stage!


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## The Paw (May 19, 2006)

Fishindude said:


> For those with experience building on piers. Do you leave it open underneath or do you install some type of "skirting" around the perimeter to keep the weather and critters out?


I had a mobile home sitting on stacked lumber piers on top of a compacted gravel pad. Laid 6 mil poly on the ground for a vapour barrier, and installed some skirting I bought from the local mobile home dealer. The skirting was 1 inch low density styrofoam with a solid sheet of vinyl siding on the outside. The same kind of vapour barrier and skirting would work on a poured foundation.

Some end vents kept moisture from building up in the crawl space during summer, and you close them up for winter and it keeps the crawl space quite a bit warmer, less problems with freezing pipes etc. The poly is easy to slide around on if you have to go underneath and fool with anything.


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## RobertDane (Feb 14, 2020)

Kevo said:


> Hey folks.
> 
> I am building a small house 24’x40’. Will be metal roof, single story and would prefer clear span. I live in north Alabama. No restrictions at all. Building without a mortgage but can borrow about $5000 at a time unsecured along with cash flow. what kind of foundation would you recommend. I have considered 6x6 treated posts concreted in the ground with 3 2x12s on top as beam. Every 8’ on piers. Any suggestions? I’m a little nervous because some folks online have reported rot after 10-15 years when treated posts are concreted in ground.


Is this a wood frame construction? My home..33' x 55' typical footing and stem wall construction. .....no slab...It holds up well. I think your type of ground would be a determining factor..I have 8 - 10 inches of topsoil and then hard clay..Believe me I've dug lots of holes here..Different bases might require another approach...


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## mreynolds (Jan 1, 2015)

Bearfootfarm said:


> They are usually enclosed by some means now but in the past it wasn't unusual to leave them open.


They used to leave them open so the chickens could go under there and eat the bugs and termites. Of course they used to do a lot of things different before AC. At least down here anyway.


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## mreynolds (Jan 1, 2015)

RobertDane said:


> _* I think your type of ground would be a determining factor*_..


I agree with this. Not enough info to really know for sure. Piers do tend to work where other foundations wont though.


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## Bearfootfarm (Jul 13, 2006)

mreynolds said:


> Of course they used to do a lot of things different before AC. At least down here anyway.


My house was built on piers and later they bricked between them.


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## mreynolds (Jan 1, 2015)

Kevo said:


> Unfortunately, I believe cardboard tubes that carpet come on, have a small diameter. The quikrete tubes at Lowes are $15 for a 12" diameter x 48" long tube.
> I would think you could use the hole itself as part of the form. - My thought was to dig a 12" diameter hole 2 1/2' deep and try to "flare out the bottom foot as best I can, fill 6" gravel, then place and secure form tube about 6" in the hole and 18" above grade. That way I could use 1 tube for every 2 piers. 24 piers = 12 Tubes = $180
> Still in the figuring it out stage!


Back in the day I built a few decks for Lowes on contract. The plan they used I was told was for any American code from hurricane to seismic code in California. It was a one size fit everything type. 

It was a 12" sonotube. It had #4 rebar and in the middle it had a 3/4" all thread J bolt 2' long. After it dried, we attached Simpson JP leveler to the 3/4" J bolt. 










https://www.strongtie.com/miscellaneousconnectors_woodconnectors/j-jp_jackpier/p/j.jp

After that, you are aces. I would not have had a problem with driving a Bobcat over her porch.


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## mreynolds (Jan 1, 2015)

Bearfootfarm said:


> My house was built on piers and later they bricked between them.


I wish I had a phone that took pictures when I worked on that house with the cypress logs as piers. It was built in 1865. Theyear after the war was over. Still no rot. Just Cypress logs in the ground for almost 200 years now.


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## mreynolds (Jan 1, 2015)

Kevo said:


> Unfortunately, I believe cardboard tubes that carpet come on, have a small diameter. The quikrete tubes at Lowes are $15 for a 12" diameter x 48" long tube.
> I would think you could use the hole itself as part of the form. - My thought was to dig a 12" diameter hole 2 1/2' deep and try to "flare out the bottom foot as best I can, fill 6" gravel, then place and secure form tube about 6" in the hole and 18" above grade. That way I could use 1 tube for every 2 piers. 24 piers = 12 Tubes = $180
> Still in the figuring it out stage!


I should also mention that we built Carthage HIgh School stadium with nothing more than 30" Sonotubes. They were in the ground 20' but that 12" Sono should be more than adequate for your single story house.


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## Bearfootfarm (Jul 13, 2006)

mreynolds said:


> I wish I had a phone that took pictures when I worked on that house with the cypress logs as piers.


The first house I owned was on piers with bricks around the outside.

When first built, the kitchen was at the end of a long open porch so if there was a fire it wouldn't burn the rest of the house. As years went by the porch was enclosed. I had to replace some sub flooring and when I tore out the old stuff I found two main beams joined together on top of one of the piers. 

They were hand hewn logs squared up and joined by mortise and tenons held together with dowel pins. 

I wish I had thought to take pictures, but that was before I had a decent camera and they still needed film. (1979-1980)

Years later a girl stopped by to ask some questions about the house for a historical survey. It seems they had never found a map of the town or surrounding area that didn't show that house, so they couldn't determine when it was built. The town was incorporated in 1891.



> The Ayden Historic District was listed on the National Register of Historic Places in 1994.


We put the blue siding on in the early 80's, and some of the big oaks that were there then are gone due to hurricanes.

https://www.instantstreetview.com/@35.471876,-77.412281,197.82h,1.16p,1z

If you scroll around you can see the barn on the left of the lot where the original owners kept their wagon and mule and you can see how the back of the house was once separated from the front.


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## mreynolds (Jan 1, 2015)

Bearfootfarm said:


> The first house I owned was on piers with bricks around the outside.
> 
> When first built, the kitchen was at the end of a long open porch so if there was a fire it wouldn't burn the rest of the house. As years went by the porch was enclosed. I had to replace some sub flooring and when I tore out the old stuff I found two main beams joined together on top of one of the piers.
> 
> ...



I love craftsmen style architecture. It is pure as the Greek (who stole it from the Akkadians). These days those new fangled "carpenters" are doing 45's on their trim that doesn't need it. 

Why do you need to miter a simple 1x4 for trim? Blasphemous I tell ya. Simple minded and easy. Like a Bic throw away lighter. No wonder houses don't last as long as they used to. 

Did I mention I was a design snob? Don't tell anyone else though.


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## mreynolds (Jan 1, 2015)

Bearfootfarm said:


> The first house I owned was on piers with bricks around the outside.
> 
> When first built, the kitchen was at the end of a long open porch so if there was a fire it wouldn't burn the rest of the house. As years went by the porch was enclosed. I had to replace some sub flooring and when I tore out the old stuff I found two main beams joined together on top of one of the piers.
> 
> ...


I love the Craftsmen style Architecture. It is pure and these days there are not many pure carpenters left. Most look for sort cuts.


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## 67drake (May 6, 2020)

Any update on this project Kevo?
Im planning a similar project and curious how yours came/comes out?


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## Rodeo's Bud (Apr 10, 2020)

The reason there are no pure carpenters anymore, is because customers don't want to pay for it. Carpenters can't do it for free.

You could have a 1,500 square foot house with Craftsman construction quality and details or you can have a 3,000 square foot McMansion for the same price.

Most go for the McMansion.

By the way, I never miter exterior trim, and only miter interior if it is cheap beveled casing. I prefer to do built up or perimeter capped Victorian style trim.

But then its back to getting paid for it.


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## Dirtdigging101 (May 13, 2020)

Here is the basics,

Concrete never comes in contact with wood, NEVER. Asphalt shingle works well between the two.

Keep soil pressure to less than 1500 lbs per sq ft

You must have lateral stability, so sometimes you need diagonal bracing.

Nearly all pressure treated wood on box stores is for exterior use, not ground contact.


Paul


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## mreynolds (Jan 1, 2015)

Dirtdigging101 said:


> Here is the basics,
> 
> Concrete never comes in contact with wood, NEVER. Asphalt shingle works well between the two.
> 
> ...


30 years ago all treated was for ground contact. Now it's not. That is just crazy in my mind. 

But I am just an old fool I guess.


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## Dirtdigging101 (May 13, 2020)

Not really, years ago it was 3 different levels of treatment, .25, .4, .6 lbs per cubic foot, big box stores had the first two, u vould order the .6,

.6 was good for wood foundation.


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## mreynolds (Jan 1, 2015)

Dirtdigging101 said:


> Not really, years ago it was 3 different levels of treatment, .25, .4, .6 lbs per cubic foot, big box stores had the first two, u vould order the .6,
> 
> .6 was good for wood foundation.


We did have bog box stores 30 years ago. We got our first about 20 years ago. It was all local lumber retailers and it was all ground contact. Arsenic treated. CCA. That and a local creosote treating company. 

It wasn't until after we got the big box stores that they catered to the weekend warrior mostly we had the other stuff. I have had decks built and on the same property the weekend warrior added on to it and ot rotted before the one I built did. They called me and asked me why. I told them to take it up with out local Lowes.


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## Fishindude (May 19, 2015)

Dirtdigging101 said:


> Here is the basics,
> 
> Concrete never comes in contact with wood, NEVER. Asphalt shingle works well between the two.
> *Incorrect - It is very common for the bottom wood plate of a structure to be treated wood, anchored down to concrete or masonry.*
> ...


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## Dirtdigging101 (May 13, 2020)

May be common but is dead wrong. There is a seal that goes there!!


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## Dirtdigging101 (May 13, 2020)

Dirtdigging101 said:


> May be common but is dead wrong. There is a seal that goes there!!


Btw, I recommend a site, if that is ok
Countryplans.com

Some very good advice there , lots of recent discussion about this topic.

Some guys there real expert

If you want contact me


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## mreynolds (Jan 1, 2015)

Dirtdigging101 said:


> Btw, I recommend a site, if that is ok
> Countryplans.com
> 
> Some very good advice there , lots of recent discussion about this topic.
> ...


Every little bit helps. I would also recommend the JLC (f Journal of light construction) You have to be an expert to post there but lots of great professional info for lurkers.

Also the breaktime forum from Fine Homebuilding. Anyone can post there.

We have some pretty good experts here too.


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## 101pigs (Sep 18, 2018)

Kevo said:


> Hey folks.
> 
> I am building a small house 24’x40’. Will be metal roof, single story and would prefer clear span. I live in north Alabama. No restrictions at all. Building without a mortgage but can borrow about $5000 at a time unsecured along with cash flow. what kind of foundation would you recommend. I have considered 6x6 treated posts concreted in the ground with 3 2x12s on top as beam. Every 8’ on piers. Any suggestions? I’m a little nervous because some folks online have reported rot after 10-15 years when treated posts are concreted in ground.


Concrete footing , Concrete foundation. Good solid, level start for the whole house.


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## Evons hubby (Oct 3, 2005)

I used limestone rocks recovered from old fireplaces to build piers for our house. No worry about rot and high enough for a good crawl space. I Put 6”x20” white oak beams on top for sills. No issues so far.


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## Danaus29 (Sep 12, 2005)

Jan 19, 2021



ycanchu2 said:


> Put all your plumbing and electric in conduit in a slab. I used flexible electrical conduit to run pex thru.....easier to make sharper turns.


I realize this post is old and the person quoted probably no longer visits (I didn't check before posting this) but I wanted to say the above advice is terrible. You can run electrical conduit through a slab but you are asking for trouble if you do it with water lines. The house next to mine has the plumbing in the concrete slab. The lines have frozen and broken and have leaked enough to cause erosion in the slab. One of the owners had the floor torn up and lines replaced twice. The next owner had problems with frozen lines. The most recent owner replaced all the water lines and moved them so they did not run through the slab.

The first house my mom bought was in a development where all the houses were on slabs. The only water lines through the slab were drain lines. No electric lines were in the slab, all were run overhead in the attics.


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## Alice In TX/MO (May 10, 2002)

Something wrong with that slab design!!!


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## kdtdenton (Dec 10, 2016)

I can tell you what I did, however I recommend you check with a structural engineer, before starting work.

My house started as 16x24 with a basic 2x8 framed floor, 16" o/c with treated lumber
I used 12 16x16 piers, with laminated PT 2x6's as beams across them. The floor frame sits on that.
My soil is moist and sandy with a hard layer of sandstone about 10" down
I dug a 16" square hole down about 12-14 inches, chipping out the sandstone until about level
I leveled the bottom of the hole with a mixture of pea gravel and sand
Then I stacked 16x16x4 solid concrete blocks up to just above grade level, keeping them level as I went.
I then got all the piers even using standard 16x8x8 cinderblocks, 8x16x1.5", 3/4 PT plywood shims, and galvanized metal to level the beams.
Then built the floor fame on top of that.


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