Tell me about slab foundations

[TwiceHorn 31653]

Looking at a house built in 1960 with a slab foundation.  On a viewing, I saw no signs of foundation problems, but it has been updated.  I did just find out that the update is at least three years old, so it isn't a flip or a cosmetic update at least partially designed to hide foundation problems.

I intend to get a structural inspection.

But I hate the idea of a slab foundation in Dallas, Texas.

I suppose if it has survived 61 years in Dallas without major problems, then it must be ok.

[Dbeasy 15167]

Slab foundations are all over Dallas and Texas. If you have to put in piers, that usually addresses the problem if they can hit rock with the piers. Even if they don’t, it usually holds well enough. $500+ per pier. 2-30 piers depending upon how bad the foundation has moved. 

[conVINCEd 21474]

I don’t think there is any rhyme or reason to it.  My parents live on a street built in the 70’s.  All slab foundations.  Half of their neighbors have had significant foundation work in the last 10 years.  My parents  just keep on ticking, no problems.  Never noticed any cracks or anything, and they are pretty OCD homeowners, so if they thought there might be a problem they would have multiple structural engineers on the case.  Pretty sure the same homebuilder built all of the houses.  My amateur theory is some slabs were poured in less than advantageous weather circumstances.  The ones with problems are all on one end of the street.

[Gil Bang 26071]

11 minutes ago, conVINCEd said:

I don’t think there is any rhyme or reason to it.  My parents live on a street built in the 70’s.  All slab foundations.  Half of their neighbors have had significant foundation work in the last 10 years.  My parents  just keep on ticking, no problems.  Never noticed any cracks or anything, and they are pretty OCD homeowners, so if they thought there might be a problem they would have multiple structural engineers on the case.  Pretty sure the same homebuilder built all of the houses.  My amateur theory is some slabs were poured in less than advantageous weather circumstances.  The ones with problems are all on one end of the street.

I'd guess that it had less to do with weather, and more to do with soil conditions/compaction. 

[Gil Bang 26071]

* i don't know shit about Texas slabs, but I've seen my share of foundation issues out here.

** post-tension slabs are the way to go 

[TwiceHorn 31653]

Dallas soil is mostly clay.  So it shrinks and swells with moisture.  And, it also seems to harbor a lot of subterranean water, meaning like creeks and things that lead to really uneven swelling and shrinkage.  So the wet seasons can be really problematic in terms of swelling, and the dry seasons are dry af, so massive shrinkage.

Even pier and beam is not immune because a pier can have most of the soil pull away from it temporarily and lose all skin friction.

Like I said, if the inspection reveals no extraordinary measures and no damage in 60 years, I'm gonna guess I'm OK?

This is Northwest Dallas, in the Disney streets.

[conVINCEd 21474]

8 minutes ago, Gil Bang said:

I'd guess that it had less to do with weather, and more to do with soil conditions/compaction. 

It’s a small street with 12 houses on each side, there shouldn’t be much soil variation.  The ones on the west side of the street have problems.  They were built last.  Lots of conclusions could be drawn there.

[TwiceHorn 31653]

10 minutes ago, conVINCEd said:

It’s a small street with 12 houses on each side, there shouldn’t be much soil variation.  The ones on the west side of the street have problems.  They were built last.  Lots of conclusions could be drawn there.

You probably have something there.  If it wasn't concrete curing problems, it was heaved or dry soil at the time of the pour, which makes Gil partly correct, also.

[bluto 4945]

Also I’ve heard homes on corners tend to have more foundation issues

[Muny_Tex 298]

I don’t have hard data on this, but it anecdotally seemed like those of us on team slab fared better than yall pier & beamers in avoiding pipe cracks/bursts/damage during the snowmaggedon last year.


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[TwiceHorn 31653]

54 minutes ago, Muny_Tex said:

I don’t have hard data on this, but it anecdotally seemed like those of us on team slab fared better than yall pier & beamers in avoiding pipe cracks/bursts/damage during the snowmaggedon last year.


Sent from my iPhone using Tapatalk

Yeah, fundamentally, that would be true.  But the pier/beam people are less proper fucked if a pipe breaks and pipe insulation is cheap and easy.

[The Original CaliHorn 68]

9 hours ago, TwiceHorn said:

Dallas soil is mostly clay.  So it shrinks and swells with moisture.  And, it also seems to harbor a lot of subterranean water, meaning like creeks and things that lead to really uneven swelling and shrinkage.  So the wet seasons can be really problematic in terms of swelling, and the dry seasons are dry af, so massive shrinkage.

Even pier and beam is not immune because a pier can have most of the soil pull away from it temporarily and lose all skin friction.

Like I said, if the inspection reveals no extraordinary measures and no damage in 60 years, I'm gonna guess I'm OK?

This is Northwest Dallas, in the Disney streets.

The neighborhood of my youth!! Crazy how this area has changed over the 4+ decades.

 

[Hefeweizen 5349]

9 hours ago, TwiceHorn said:

Looking at a house built in 1960 with a slab foundation.  On a viewing, I saw no signs of foundation problems, but it has been updated.  I did just find out that the update is at least three years old, so it isn't a flip or a cosmetic update at least partially designed to hide foundation problems.

I intend to get a structural inspection.

But I hate the idea of a slab foundation in Dallas, Texas.

I suppose if it has survived 61 years in Dallas without major problems, then it must be ok.

Older slabs are frequently fine, especially if they don't show signs of failure.  Mainly because the design was based on a factor of safety and as a result the thickness of the concrete was probably 6 or 7 inches.  The 5 inch slab with toe beams only works if it moves as a unit and there is "acceptable" movement in that foundation.  I'm not a structural engineer, but work with enough of them to know post-tensioned slabs are only used because they are so much cheaper with the reduction in concrete volume.  None of the structural guys I know do residential though.

Do you know how thick the slab is?

Edited February 3, 2022 by Hefeweizen

[TwiceHorn 31653]

23 minutes ago, The Original CaliHorn said:

The neighborhood of my youth!! Crazy how this area has changed over the 4+ decades.

 

This is Sparkman Club Estates, to be precise.  I really know nothing about it, but it seems really quite nice.

Dallas has an abundance of what seem to be great little hoods kind of all over the place.

We're in kind of a dilemma, because one of the main reasons for downsizing is to reduce the property tax burden, which means reducing purchase price/property value.  We could afford more house than what we're looking at, but have to restrain ourselves to stick with that goal.

NW Dallas seems to be one hood that is currently a bit undervalued, yet isn't some kind of urban/suburban adventure.

[TwiceHorn 31653]

29 minutes ago, Hefeweizen said:

Older slabs are frequently fine, especially if they don't show signs of failure.  Mainly because the design was based on a factor of safety and as a result the thickness of the concrete was probably 6 or 7 inches.  The 5 inch slab with toe beams only works if it moves as a unit and there is "acceptable" movement in that foundation.  I'm not a structural engineer, but work with enough of them to know post-tensioned slabs are only used because they are so much cheaper with the reduction in concrete volume.  None of the structural guys I know do residential though.

Do you know how thick the slab is?

Not yet.  It would be my intention to have a normal residential inspection, a pool inspection, and a structural engineering inspection.

I am given to understand that a number of houses in the area were "Fox & Jacobs," which some may recall as being a mass builder around Dallas or the state.  Apparently, though, Fox & Jacobs homes were actually pretty well built.  We've been looking at late 50s, early 60s built homes all over North Dallas and the vast majority are pier & beam.  A lot of slabs in this hood, though.

The other question I have is plumbing in slabs.  The slab itself may be fine, but what about the pipes buried in that shit?  I have vague knowledge that 50 year old pipes (cast iron, clay, what have you) are ripe to fail in all kinds of settings.

Edited February 3, 2022 by TwiceHorn

[deadshank 24653]

10 hours ago, Gil Bang said:

* i don't know shit about Texas slabs, but I've seen my share of foundation issues out here.

** post-tension slabs are the way to go 

Until you want to remodel and add / move plumbing in the slab. 
 

 

[TwiceHorn 31653]

3 minutes ago, deadshank said:

Until you want to remodel and add / move plumbing in the slab. 
 

 

Ironic that you mention that.

The kitchen has a huge island that would seem ripe for mounting an oven, microwave, etc. yet nothing is in it, except the sink.

And, as a result, most of the kitchen appliances are on the wall opposite, including a range, as opposed to a cooktop/oven.  I presume because no one wanted to run more plumbing/wiring through the slab for stuff on the island.  Although I doubt it's a post-tension slab.

It's not that big a deal, but a range (meaning oven and cooktop together) just reeks "apartment."  And, somewhat surprisingly, it's not a Wolf or Viking, as is trendy, but a fairly substantial looking, but also electronic Samsung.

[deadshank 24653]

Most early 60s houses are slab on grade AKA slab on ground (SOG). Lots of select fill, soil compaction, rebar and forms.  In good, monolithic soil conditions they work well with the right size house.    
 

I live in Houston on the west side and the soil conditions are hit and miss.  My house was built in 1962.  It has SOG and has once been repaired for a partial failure.   Many houses in my neighborhood are having their SOG foundations repaired with added piers.  
 

All but a few of the houses we build are structural slabs that are engineered to the Nth degree.  
 

The science of slabs has evolved and become more attuned to extremely localized soil reports.  Our construction contract relies heavily on a section regarding soil reports and selection of slab with the burden placed on the property owner and engineer to survey the lot’s soil conditions and select the proper slab.  After that it is our job to follow instructions and get the proper engineering inspections along the way to ensure the slab will be built according to Hoyle. 
 

What could possibly go wrong?

[TwiceHorn 31653]

5 minutes ago, deadshank said:

In good, monolithic soil conditions they work well with the right size house.    
 

Yeah, it's that monolithic that worries me.  I think there are areas of Dallas where the clay soil is pretty monolithic and it depends heavily on subterranean water. 

And Dallas is shot through with surface creeks, which, in addition to flooding problems, particularly with overcoverage of lots in new construction, comes with subterranean "tributaries" or some such thing that makes the soil not monolithic, maybe in composition, but not in exposure to groundwater.  

It's possible this is an area that lacks that subterranean water.  Not a lot shows on the map.

[TwiceHorn 31653]

Another question.  This is a midcentury modern that was pretty seriously updated in 2019.  The floorplan was open to begin with, but I imagine a wall or two was knocked down, especially to open up the kitchen for that monstrous, four-seat island.

It does have a second story, so I imagine they had to be careful about load bearing walls and such.

But does that kind of remodeling overstress a slab?  So my theory about having lasted 60 years may not be valid any longer?

[deadshank 24653]

3 minutes ago, TwiceHorn said:

Yeah, it's that monolithic that worries me.  I think there are areas of Dallas where the clay soil is pretty monolithic and it depends heavily on subterranean water. 

And Dallas is shot through with surface creeks, which, in addition to flooding problems, particularly with overcoverage of lots in new construction, comes with subterranean "tributaries" or some such thing that makes the soil not monolithic, maybe in composition, but not in exposure to groundwater.  

It's possible this is an area that lacks that subterranean water.  Not a lot shows on the map.

If you’re that worried about it then the area may not be for you, or you’re overthinking it or you may want to build your own place with an engineered structural slab (placed in potentially less than perfect soil).  
 

Not mocking you.  It’s just there is no perfect answer in this neck of the woods.  You just deal with it.  

[TwiceHorn 31653]

10 minutes ago, deadshank said:

If you’re that worried about it then the area may not be for you, or you’re overthinking it or you may want to build your own place with an engineered structural slab (placed in potentially less than perfect soil).  
 

Not mocking you.  It’s just there is no perfect answer in this neck of the woods.  You just deal with it.  

Definitely overthinking.  I have some scar tissue with foundation problems.  My parents house had an area where the piers slipped and there was no bedrock at any reasonable depth because of subterranean Turtle Creek.

And I have legal experience with, as you note, a foundation that was missing (from the foundation plan) one parallam on a central beam in a $2M-3M house.

And, yes, I have built my own with 18 foot belled piers.  That leads to a mid-five-figures property tax bill that I can't see carrying into retirement.

I'm just trying to gather information to soothe my mind about making an offer on something with a slab.  Ordinarily, I would avoid, but this house is one charming motherfucking pig.

Edited February 3, 2022 by TwiceHorn

[deadshank 24653]

1 minute ago, TwiceHorn said:

Definitely overthinking.  I have some scar tissue with foundation problems.  My parents house had an area where the piers slipped and there was no bedrock at any reasonable depth because of subterranean Turtle Creek.

And I have legal experience with, as you note, a foundation that was missing (from the foundation plan) one parallam on a central beam in a $2M-3M house.

And, yes, I have built my own with 18 foot belled piers.  That leads to a mid-five-figures property tax bill that I can't see carrying into retirement.

In the end we dig our own graves. 

[conVINCEd 21474]

Moving to the Disney streets to reduce your tax burden is a very strong humble brag.

[TwiceHorn 31653]

11 minutes ago, conVINCEd said:

Moving to the Disney streets to reduce your tax burden is a very strong humble brag.

Yeah, sorry, white people problems.

[South Austin 52673]

Central Texas has some of the best and worst conditions for slab foundations.  Best are the areas of limestone and other rock formations, like West Austin and Northwest San Antonio.  Provided the engineer and/or concrete sub didn't completely fuck things up, slabs in those areas won't move much over time. 

But not far from those areas are large patches of high-plasticity clays, and when you add the common Texas weather pattern of alternating drought and rainy periods, slab performance is more problematic, especially in cheaper production homes where a builder might not spend as much on quality engineering. 

[TwiceHorn 31653]

Yeah, so, partly thanks to @luke duke, I found out the second story was added in 2018.

No slab for us.

[Sbbruin 21905]

Easy how-to foundation repair video

 

[CooterBrown 18039]

If it’s been there 60 years and it hasn’t moved yet, it’s not going to.

[TwiceHorn 31653]

21 minutes ago, CooterBrown said:

If it’s been there 60 years and it hasn’t moved yet, it’s not going to.

It's only been there three years with a second story on it.

Hard pass.

Also, sellers disclosure said "hairline cracks" in sheetrock.  That may have been settling, but slab, Dallas, added second story.

Edited February 4, 2022 by TwiceHorn

[Onboard 2.0 9083]

14 hours ago, Muny_Tex said:

I don’t have hard data on this, but it anecdotally seemed like those of us on team slab fared better than yall pier & beamers in avoiding pipe cracks/bursts/damage during the snowmaggedon last year.


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Yeah because they didn’t insulate the crawl space properly.

Slabs are fine, but have less efficiency than a crawl space in that HVAC can be routed there, pipes are completely accessible, and floors tend to be warmer on crawlspace homes. 

A crawlspace is more expensive to build typically.

[TwiceHorn 31653]

Just a point of curiosity.  

I know that when piers are added to a slab, they are "driven" into the ground typically in segments.

I guess they have to dig/excavate under the slab to get to where the pier is needed?  That seems like it could raise a whole other set of problems.

Based on this conversation, I think I am going to exclude slabs from consideration altogether.  I just really don't like the idea around here, if anywhere.

This place is a priceless source of practical information.  Thanks for the contributions.

[CooterBrown 18039]

Just a point of curiosity.  
I know that when piers are added to a slab, they are "driven" into the ground typically in segments.
I guess they have to dig/excavate under the slab to get to where the pier is needed?  That seems like it could raise a whole other set of problems.
Based on this conversation, I think I am going to exclude slabs from consideration altogether.  I just really don't like the idea around here, if anywhere.
This place is a priceless source of practical information.  Thanks for the contributions.

I had 39 piers installed in my last house for like $35,000.

They dig a hole until they hit rock. Fill it with concrete and install a permanent Jack to level the house. Lock it in place and backfill the hole with dirt.

The thing is all houses settle. If it’s an old house, say, over 20 years old, it is most likely not going to move any more. You don’t need to fix it unless it has caused plumbing damage. You can just do the sheet rock repairs and forget about it. If you have really shitty soil or drainage, you’ll need to fix it regardless of age. That was the issue with my house. The back yard drained slightly to the house. Water wouldn’t pool but under the surface, it caused a lot of soil movement that continued to cause problems. If you go down Shoal Creek, the houses on the east side of the street all have foundation issues to this day because that hillside drains under those houses.

[Jiggy-Z 3440]

On 2/3/2022 at 7:20 AM, deadshank said:

Until you want to remodel and add / move plumbing in the slab. 
 

 

Concrete contractor here.

Back in 2003 we were working on the convention center Hilton in Austin adding some curb on the 6th, 7th and 12th floor.  We had to dowel into the slab to affix the curb and the the scanner guys fucked up and didn't mark all of the pt cables and sure enough we hit about 5 of them.  Sounded like a gun going off and a couple of them shot out the side of the building.  They were about $3,500.00 each to fix.

That building was plagued with bad design and execution.  We got to fix the 5th level of the below ground parking garage too.  The wall waterproofing failed and th French drain system was shit.  During the rainy season that lowest level had a bout 3 feet of water in it.

[Nueces River Rat 5569]

On 2/4/2022 at 9:31 AM, CooterBrown said:

I had 39 piers installed in my last house for like $35,000.

They dig a hole until they hit rock. Fill it with concrete and install a permanent Jack to level the house. Lock it in place and backfill the hole with dirt.

The thing is all houses settle. If it’s an old house, say, over 20 years old, it is most likely not going to move any more. You don’t need to fix it unless it has caused plumbing damage. You can just do the sheet rock repairs and forget about it. If you have really shitty soil or drainage, you’ll need to fix it regardless of age. That was the issue with my house. The back yard drained slightly to the house. Water wouldn’t pool but under the surface, it caused a lot of soil movement that continued to cause problems. If you go down Shoal Creek, the houses on the east side of the street all have foundation issues to this day because that hillside drains under those houses.

Pretty much this is the process...  Cost me $25,000 to repair our first home in the late 90's.    Writing that check sucked.

[TwiceHorn 31653]

2 minutes ago, Nueces River Rat said:

Pretty much this is the process...  Cost me $25,000 to repair our first home in the late 90's.    Writing that check sucked.

Yeah, I'd kind of like to avoid that.

[gyroprotagonist 2595]

i am sad there are no Fat Tony/Drank Blvd. posts on this thread.  

But i got nothing to add.  In Dallas but on pier and beam.  the bedrock is fairly shallow in my 'hood. 

[FORTY NINE TO ZERO 2652]

team pier and beam here.  no foundation issues and easy to update/move piping and electricity.  

my architecture prof at UT years ago told me foundations in a good chunk of texas  were headaches waiting to happen 

[Bevo 13612]

4 hours ago, Jiggy-Z said:

Concrete contractor here.

Back in 2003 we were working on the convention center Hilton in Austin adding some curb on the 6th, 7th and 12th floor.  We had to dowel into the slab to affix the curb and the the scanner guys fucked up and didn't mark all of the pt cables and sure enough we hit about 5 of them.  Sounded like a gun going off and a couple of them shot out the side of the building.  They were about $3,500.00 each to fix.

That building was plagued with bad design and execution.  We got to fix the 5th level of the below ground parking garage too.  The wall waterproofing failed and th French drain system was shit.  During the rainy season that lowest level had a bout 3 feet of water in it.

I am doing a conditioned crawl space and best practices say to install a sump pump. But, if waterproofing is required on the walls and floor and closed cell foam installation is installed and a dehumidifier is used, where the fuck would the water come from?  The house isn't in a flood zone: It is on the plateau of a hill at 2300ft. And everything should be set up where water drains away from the house.

[Bevo 13612]

4 minutes ago, ONE YARD said:

team pier and beam here.  no foundation issues and easy to update/move piping and electricity.  

my architecture prof at UT years ago told me foundations in a good chunk of texas  were headaches waiting to happen 

I assume that the garage is on slab. Wouldn't you have issues at the junction between the garage and the house because they would move differently in the soil.

[FORTY NINE TO ZERO 2652]

4 minutes ago, Bevo said:

I assume that the garage is on slab. Wouldn't you have issues at the junction between the garage and the house because they would move differently in the soil.

it’s a separate structure entirely. 

 

full disclosure. my main house was built in 1886 and the slab garage was in 2015ish. lol. 

 

that said my parents house is pier and beam with an attached garage built in the late 80s.  it’s four steps down to a garage.   crazy 80s monster that was designed by architects on a lot of coke, but never had any issues.  

Edited February 8, 2022 by ONE YARD

[Bevo 13612]

1 minute ago, ONE YARD said:

it’s a separate structure entirely. 

 

full disclosure. my main house was built in 1886 and the slab garage was in 2015ish. lol. 

 

that said my parents house is pier and beam with an attached garage built in the late 80s.  it’s four steps down to a garage.   never had any issues.  

I assume most pier and beam homes are done that way. I'm just curious to know why it doesn't create problems. I'll be building a home soon and I'd like to know everything before I start. Unfortunately, every time I think I know something, new questions are raised. Like pipes will go into interior walls via the crawl space. However, the electrical panel and radiant heating stuff and plumbing will be in the attached garage. So, I guess this means that the electrician, plumber, and radiant heat guy will need to put pipes in the floor of the garage before the garage slab and concrete walls for the conditioned crawl space are poured. Then, they will have to come back again to run the pipes to the proper spot before the subfloors are done and then will have to come back a third time after the framing is done and a fourth time to finish up after drywall and cabinetry are in place.

[Onboard 2.0 9083]

16 minutes ago, Bevo said:

I am doing a conditioned crawl space and best practices say to install a sump pump. But, if waterproofing is required on the walls and floor and closed cell foam installation is installed and a dehumidifier is used, where the fuck would the water come from?  The house isn't in a flood zone: It is on the plateau of a hill at 2300ft. And everything should be set up where water drains away from the house.

Typically unless the outside grade is higher then the inside grade there should be no need for a sump pump.  Water could be coming under the footings,  but that would indicate a variable/seasonal watertable. I've never specified a sump pump unless it's a basement or excavated crawl space.  I'd be asking around with local contractors to see what they say.

[FORTY NINE TO ZERO 2652]

8 minutes ago, Bevo said:

I assume most pier and beam homes are done that way. I'm just curious to know why it doesn't create problems. I'll be building a home soon and I'd like to know everything before I start. Unfortunately, every time I think I know something, new questions are raised. Like pipes will go into interior walls via the crawl space. However, the electrical panel and radiant heating stuff and plumbing will be in the attached garage. So, I guess this means that the electrician, plumber, and radiant heat guy will need to put pipes in the floor of the garage before the garage slab and concrete walls for the conditioned crawl space are poured. Then, they will have to come back again to run the pipes to the proper spot before the subfloors are done and then will have to come back a third time after the framing is done and a fourth time to finish up after drywall and cabinetry are in place.

their stuff is all on the garage wall next to the house. so it goes right into the crawl space.    nothing goes through their garage slab. 

[Onboard 2.0 9083]

18 minutes ago, Bevo said:

I assume that the garage is on slab. Wouldn't you have issues at the junction between the garage and the house because they would move differently in the soil.

A garage slab will be on grade, but the actual garage CMU foundation walls will be built atop a 20" x 12" continuous footing (w/(2) cont. #4 bars for tensile strength) at the same depth as the house foundation footing.  The slab is poured after the CMU foundation walls of the garage are built, and then there's an expansion joint between the edge of the slab, and the foundation wall so they can move independently of each other.  The slab area should be prepped with a min. of 4" of properly compacted, porous gravel so settlement shouldn't be an issue.

[Jiggy-Z 3440]

13 hours ago, Bevo said:

I am doing a conditioned crawl space and best practices say to install a sump pump. But, if waterproofing is required on the walls and floor and closed cell foam installation is installed and a dehumidifier is used, where the fuck would the water come from?  The house isn't in a flood zone: It is on the plateau of a hill at 2300ft. And everything should be set up where water drains away from the house.

Water is always set to drain away from the house.  The issue is what to do with the water that pools around the outside of the wall in the soil.  There needs to be a way to remove it.  Even on a plateau or a hill water will find its way to the lowest point, sometimes even traveling against gravity and uphill through pressure applied in seams and voids.

Here in central Texas most houses that have split levels have a French Drain at the perimeter which is day lighted downhill, which eliminates the need for a sump pump set up.

However when you have a true basement, there is usually a sub slab French drain and a perimeter French drain which are routed to an interior sump pit/pump.

In 26 years in Central Texas I have never installed a residential sump set up in a split level "hillside" house as there has always been a means to remove water through gravity.

We install sump pits in elevator pits all the time, although those are too small to warrant any type of individual drainage system.

In the example I gave with the Hilton, the sub floor French Drain was installed with gravel but it was mixed with wet limestone fill creating an almost concrete like encapsulation of the drain pipe which did not allow the sub slab drain system to work.  On top of that, the wall waterproofing failed due to poor install and improper exterior wall drainage system installation.  The amount of water infiltrating was too great for the sump pit/pump set up they had.

The solution was to cut into the floor and install an entirely new sub floor French drain system, an additional sump pit/pump, and enlargement of the existing sump pit/pump set up.  The basement walls had to be treated from the inside with a crystallizing waterproofing element to keep them from weeping. Additionally, the walls received over 800 core holes which were fitted with an interior pvc manifold system that fed down into the sub slab drain.

[Bevo 13612]

45 minutes ago, Jiggy-Z said:

However when you have a true basement, there is usually a sub slab French drain and a perimeter French drain which are routed to an interior sump pit/pump.

Does the architect call that out in his plans or does the builder just ask for it if he thinks that it is necessary? Does the landscape architect do the two french drains or the excavator or the foundation subcontractor? Basically, I'm wondering if the homeowner needs to ask for it or if the builder makes the decision.

[Jiggy-Z 3440]

3 minutes ago, Bevo said:

Does the architect call that out in his plans or does the builder just ask for it if he thinks that it is necessary? Does the landscape architect do the two french drains or the excavator or the foundation subcontractor? Basically, I'm wondering if the homeowner needs to ask for it or if the builder makes the decision.

What I usually see is the architect draws something up but with very little detail-more of a memory jog for the engineer.  The structural engineer will detail the drains with the architectural drawing in mind, routing the system around any possible architectural obstructions etc. Either way that stuff is usually not left to the builder. 

Either the plumber or the concrete sub will do the drains.  Pump and exit piping is the plumber.  Keep in mind this is what is done in central Texas.  Also, for residential here, concrete sub usually does the mass excavation.  Electrical sub will route conduit etc.

I don't do a whole lot of residential, but on commercial projects, these details will appear in Civil, Arch, Structural, and MEP drawings.  Additionally each of the subs will submit shop drawings with their interpretations of the drawings for approval by the appropriate designer facilitated by the GC.

[Bevo 13612]

2 minutes ago, Jiggy-Z said:

What I usually see is the architect draws something up but with very little detail-more of a memory jog for the engineer.  The structural engineer will detail the drains with the architectural drawing in mind, routing the system around any possible architectural obstructions etc. Either way that stuff is usually not left to the builder. 

Either the plumber or the concrete sub will do the drains.  Pump and exit piping is the plumber.  Keep in mind this is what is done in central Texas.  Also, for residential here, concrete sub usually does the mass excavation.  Electrical sub will route conduit etc.

I don't do a whole lot of residential, but on commercial projects, these details will appear in Civil, Arch, Structural, and MEP drawings.  Additionally each of the subs will submit shop drawings with their interpretations of the drawings for approval by the appropriate designer facilitated by the GC.

Thanks. I am building a vacation home in the mountains and don't have a builder yet. The architect and the structural engineer live in the Midwest so I'm not sure if they know what is done in the Rockies. The first builder I worked with wanted about $350/sq ft which was way out of line at the time (probably not so out of line with prices now). So I decided to do SIP construction and have the timber framers take the project to lock-in stage. I was speaking with the excavator yesterday and he warned me, though that there were a lot of subs in the area who were taking people's money. So, I'll probably go back to getting a builder but since I have most things already priced out, I'm going to finish all that before I find someone.

I asked the excavator if he also did foundations and he said that he had a concrete guy but he was getting booked out so if I wanted to do it this year I would have to put money down soon. I want to tell them exactly what I expect because I'm not confident that they will do things right. So, I realized that I didn't know what I need to know like potentially needing an interior and exterior french drain system, who decides where to put in anchor bolts for the sill plate, when to do the plumbing rough-in from the garage to the house, tie in to the sewer and probably other stuff I'm unfamiliar with.

[Jiggy-Z 3440]

21 minutes ago, Bevo said:

Thanks. I am building a vacation home in the mountains and don't have a builder yet. The architect and the structural engineer live in the Midwest so I'm not sure if they know what is done in the Rockies. The first builder I worked with wanted about $350/sq ft which was way out of line at the time (probably not so out of line with prices now). So I decided to do SIP construction and have the timber framers take the project to lock-in stage. I was speaking with the excavator yesterday and he warned me, though that there were a lot of subs in the area who were taking people's money. So, I'll probably go back to getting a builder but since I have most things already priced out, I'm going to finish all that before I find someone.

I asked the excavator if he also did foundations and he said that he had a concrete guy but he was getting booked out so if I wanted to do it this year I would have to put money down soon. I want to tell them exactly what I expect because I'm not confident that they will do things right. So, I realized that I didn't know what I need to know like potentially needing an interior and exterior french drain system, who decides where to put in anchor bolts for the sill plate, when to do the plumbing rough-in from the garage to the house, tie in to the sewer and probably other stuff I'm unfamiliar with.

Kind of out of my area of expertise.  Get a builder.  Good to ask questions though.  Hope some of this helped.