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Lynn Javoroski CSI CCS LEED® AP SCIP Affiliate
Senior Member
Username: lynn_javoroski

Post Number: 1148
Registered: 07-2002


Posted on Thursday, November 18, 2010 - 01:36 pm:   Edit PostDelete PostPrint Post

Contractor wants to use TegraTite-Plus. I have no experience with the product. Does anyone have an opinion to offer?
Lynn Javoroski CSI CCS LEED® AP SCIP Affiliate
Senior Member
Username: lynn_javoroski

Post Number: 1149
Registered: 07-2002


Posted on Thursday, November 18, 2010 - 02:30 pm:   Edit PostDelete PostPrint Post

Just to clarify, what is really needed for the project is foundation wall dampproofing that can be applied in cold weather - like closer to 30F. Any suggestions would be helpful.
Ellis C. Whitby, AIA, PE, CSI, LEED® AP
Senior Member
Username: ecwhitby

Post Number: 74
Registered: 03-2003
Posted on Thursday, November 18, 2010 - 02:59 pm:   Edit PostDelete PostPrint Post

Move the project south?

Seriously, I have not used that particular Bentonite system. I know that various manufacturers of Bentonite/HDPE systems list application temperatures down to 30F and lower.
Richard L Matteo, AIA, CSI, CCS
Senior Member
Username: rlmat

Post Number: 404
Registered: 10-2003
Posted on Thursday, November 18, 2010 - 03:08 pm:   Edit PostDelete PostPrint Post

Lynn,

Check out their website.
The product data indicates it is good to -40 degrees.
The fact that the product is manufactured in Bloomington, MN would indicate that it probably performs well in cold weather
Lynn Javoroski CSI CCS LEED® AP SCIP Affiliate
Senior Member
Username: lynn_javoroski

Post Number: 1150
Registered: 07-2002


Posted on Thursday, November 18, 2010 - 04:14 pm:   Edit PostDelete PostPrint Post

Thanks - I think (grin). The project is in northern Iowa, and it's not the performance I'm concerned about, it's the application temperature. The CM has scheduled the application for January. Yeah, I know.
Jim Sliff
Senior Member
Username: jim_sliff

Post Number: 8
Registered: 08-2010


Posted on Thursday, November 18, 2010 - 04:30 pm:   Edit PostDelete PostPrint Post

"Installation may proceed on damp or frozen surfaces, but standing water must be removed."

Right from the product data sheet.

I had to look it up - I'd not heard of it either, but from the description it sounds similar to Paraseal, which I think handles -25F temperature during installation (as it hits about 55F on a cold day here I shiver just thinking about minus-anything!).
Lynn Javoroski CSI CCS LEED® AP SCIP Affiliate
Senior Member
Username: lynn_javoroski

Post Number: 1151
Registered: 07-2002


Posted on Thursday, November 18, 2010 - 04:37 pm:   Edit PostDelete PostPrint Post

But don't y'all think that product is overkill for damp-proofing a foundation wall? With no basement? Aren't there other products that will allow application in below-40F temps that aren't as expensive?

And according to the TegraSeal web site, it's a better-than ParaSeal, because the company was started by folks who used to be with ParaSeal.
Wayne Yancey
Senior Member
Username: wayne_yancey

Post Number: 377
Registered: 01-2008


Posted on Thursday, November 18, 2010 - 04:56 pm:   Edit PostDelete PostPrint Post

Lynn,

I just replied to your APB but forgot to re-register. Again. It will show up eventually after it has been thorougly vetted by the discussion forum monitor.

Wayne
(Unregistered Guest)
Unregistered guest
Posted on Thursday, November 18, 2010 - 04:50 pm:   Edit PostDelete PostPrint Post

Lynn,

What is maximum frost depth in winter in Iowa?

Consider Soprema "SOPRALENE FLAM 180" SBS modified heat applied waterproofing solution for vertical applications with drainage composite and / or protection sheets of rigid XPS insulation

Advantages: Defined consistent thickness; no application temperature restrictions, heat diffusion provides for strong adhesion over inconsistent and/or rough and uneven substrates.

Still overkill from the conditions you have described. Popular in Alberta where nighttime ambient temperature can be -40 deg F or C, and frost depth of 60 inches or more.

Not certain anything is required if there is not a conditioned space on opposite side of foundation wall. Sounds like you simply have a deep grade beam because of the frost depth.

Is there a hydrostatic pressure?
Lynn Javoroski CSI CCS LEED® AP SCIP Affiliate
Senior Member
Username: lynn_javoroski

Post Number: 1152
Registered: 07-2002


Posted on Thursday, November 18, 2010 - 06:32 pm:   Edit PostDelete PostPrint Post

Since we are not even including drain tile, I doubt there is any hydrostatic pressure. Originally, I had specified a standard asphaltic damp-proofing, but since it's going to be done in January, as the CM scheduled, the contractor is suggesting the product.

Temps will not likely get down to -40, but could easily get down to 20F. Frost depth would be no more than 48 inches.
J. Peter Jordan (Unregistered Guest)
Unregistered guest
Posted on Friday, November 19, 2010 - 09:52 am:   Edit PostDelete PostPrint Post

I would just like to go on record as reporting that here in south Texas (south of I-10), the frost depth is 0 inches.
Ronald L. Geren, AIA, CSI, CCS, CCCA, SCIP
Senior Member
Username: specman

Post Number: 887
Registered: 03-2003


Posted on Friday, November 19, 2010 - 01:52 pm:   Edit PostDelete PostPrint Post

And I would like to go on record as reporting that here in Phoenix, what's "frost"?
Ron Geren, AIA, CSI, CCS, CCCA, SCIP
www.specsandcodes.com
Richard Gonser AIA CSI CCCA
Senior Member
Username: rich_gonser

Post Number: 11
Registered: 11-2008
Posted on Friday, November 19, 2010 - 02:19 pm:   Edit PostDelete PostPrint Post

Isn't that the frozen moisture that's outside my beer mug?
Lynn Javoroski CSI CCS LEED® AP SCIP Affiliate
Senior Member
Username: lynn_javoroski

Post Number: 1153
Registered: 07-2002


Posted on Friday, November 19, 2010 - 02:49 pm:   Edit PostDelete PostPrint Post

"Frost" could be what's on the shoulder of the next young woman y'all try to talk to...

Or what y'all are desperately looking for in August...
Anne Whitacre, FCSI CCS
Senior Member
Username: awhitacre

Post Number: 1057
Registered: 07-2002


Posted on Friday, November 19, 2010 - 02:56 pm:   Edit PostDelete PostPrint Post

Lynn.... you know that if the contractor proposes some product that you've never heard of, you're supposed to put the burden of proof on them to demonstrate product suitability, right? Here in the great northwet, we don't have anything that is considered "dampproofing" -- either it keeps the water out or it doesn't. That asphaltic stuff dissolves after a few years if the soil is acidic enough, and so it isn't worth the bucket it comes in.
So, I see two options here: either you need water proofing or you don't. if you dont, why not just put up a protection board (some fan-folding thing) with a drainage board and be done with it? you can put that up even if its -50 outside.
if you need waterproofing, then look at waterproofing products. I will reserve my opinion about bentonite, since I'm sure I've ranted about it before in other venues.
Lynn Javoroski CSI CCS LEED® AP SCIP Affiliate
Senior Member
Username: lynn_javoroski

Post Number: 1154
Registered: 07-2002


Posted on Friday, November 19, 2010 - 03:05 pm:   Edit PostDelete PostPrint Post

Anne, Thanks for the note of sanity. I'll bring both things up to the architect. I think you're right; we really don't need anything.

This whole situation probably came about because they were dithering about drainage tile necessity. And we haven't really re-visited the application with a clear head since.

This project is one I've complained (not my first word choice) about before with a CM who only thinks he knows what he's doing - and who has somehow hired a bunch of his cronies, although he says he's put it out for bids...it's probably a good thing that I'll never meet him face-to-face.
John Bunzick, CCS, CCCA, LEED AP
Senior Member
Username: bunzick

Post Number: 1271
Registered: 03-2002
Posted on Friday, November 19, 2010 - 06:08 pm:   Edit PostDelete PostPrint Post

They will be backfilling fairly quickly if the temperatures are that low because they have to prevent the ground under the footings from freezing. If there is a product that can be applied to green concrete right after the forms are stripped, the exothermic reaction of the conrete curing, combined with some blankets or other cover, may very likely allow a more conventional dampproofing to be applied. I don't know the product, but I would be concerned whether bentonite waterproofing would provide the same purpose as dampproofing. Betonite must be wet to work, remember, kind of the opposite of what you may want to do with dampproofing.
Ron Beard CCS
Senior Member
Username: rm_beard_ccs

Post Number: 359
Registered: 10-2002


Posted on Friday, November 19, 2010 - 06:38 pm:   Edit PostDelete PostPrint Post

I would be cautious about adding a drainage product against the wall unless there is a foundation drainage system available to carry any water away otherwise water will collect and stand directly against the wall. When collected, water will most likely seek the path of least resistance away from the structure; hopefully, not into the buildings footprint.

A layer of a homasote-like product [do they still make an asphaltic impregnated product?] will work as an inexpensive, easy to use protection course.
"Fast is good, but accurate is better."
.............Wyatt Earp
Mark Gilligan SE,
Senior Member
Username: mark_gilligan

Post Number: 333
Registered: 10-2007
Posted on Saturday, November 20, 2010 - 12:09 am:   Edit PostDelete PostPrint Post

Bentonite may need to be wet to work but it does not want to be wet to instal. When the water occurs the bentonite will then expand thus providing protection.

One option is to use xypex in the concrete mix. Pull the forms and backfill.

A more basic question is why do you need damproofing on foundation wall if there is no basement? Why do you need to keep water from flowing through the foundation wall if there is no habitable space on the other side?
Ron Beard CCS
Senior Member
Username: rm_beard_ccs

Post Number: 360
Registered: 10-2002


Posted on Saturday, November 20, 2010 - 01:53 am:   Edit PostDelete PostPrint Post

<<Why do you need to keep water from flowing through the foundation wall if there is no habitable space on the other side?>>

Water is to a building as cancer is to the human body. You just don't want in your system. Surely there must a Murphy's Law somewhere that says if water is under a building it will find a way in.

Check out all the past 4Specs threads on moisture attacks on slabs-on-grade.
"Fast is good, but accurate is better."
.............Wyatt Earp
Jim Sliff
Senior Member
Username: jim_sliff

Post Number: 9
Registered: 08-2010


Posted on Saturday, November 20, 2010 - 04:12 am:   Edit PostDelete PostPrint Post

"One option is to use xypex in the concrete mix. Pull the forms and backfill."

I've seen that done only as a backup to some kind of membrane system - the "Xypex-type" installed as a secondary protection system. Since after the moisture has left he concrete it has no function, it's (to me) a backup to (what should be) the primary waterproofing system. I'm not pointing this at Xypex alone, as all the crystalline-type "waterproofing" materials are similar despite marketing data to the contrary - i.e. differences are in the chemistry but the end result is a "blockade" against water migration. They do a specific job well, but usually as a remedial or backup system.

It's quite common here (like Ron I'm not quite sure what Frus...errr, frazt....uhhh - "frost" is) for such additives to be required, but not flying solo - however the asphalt emulsion/mastic "dampproofing" materials that used to be the "standard" Iseem to be losing ground quickly. Xypex et al combined with either 1) 60 mils of urethane, protection board and drain mat, 2) a sheet-goods product laid inside the forms with a vertical grade installed after stripping, or 3) a 60-80 mil, plural-component spray, fluid-applied polyurea membrane are not uncommon (with polyurea making a lot of headway due to extremely short backfill times (60 seconds or so).

Polyurea can be applied down to roughly -30F; with sheet goods temp requirements are all over the map; emulsions usually have pretty strict time windows. In my experience polyurea is the best of he bunch as far as performance goes but it can be costly depending on square footage and location (there are somewhat limited numbers of applicatiors.). Probably the most bulletproof on-grade, pre-pour barrier/membrane I've seen in 6 oz geotextile fabric infused (by spraying the stuff on the ground) with 80+ mils of pure polyurea. An inspector can walk on the stuff in 45-60 seconds, do his thing and the concrete pour can be done immediately. I stay away from emulsions unless it's a completely benign application or a very small area excavated for repair - like the *outer* side of planter walls (I won't specify it for the inside of planters - I've seen far too many cases of roots going to town on the stuff, plus it seems to stiffen with age unlike polyureas and polyurethanes.)
(Unregistered Guest)
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Posted on Saturday, November 20, 2010 - 12:58 pm:   Edit PostDelete PostPrint Post

The idea that after the moisture leaves the concrete Xypex has no function reflects a mis understanding. First because a significant amount of the mix water never leaves the concrete. It is captured in the pores in the concrete and the Xypex remains activated. Also if the concrete at the surface dries out the Xypex will be reactivated when subject to additional water.

Unlike most waterproofing systems Xypex is self healing. What is most effective a less than perfect system that heals or a "good" system that is compromised by cracks or installation defects?

I believe that if you look into the data on Xypex that you will find that it is probably more effective than you believe. Since the original goal is to provide dampproofing, which aims to control moisture flow not prevent it, my sense is that Xypex would be very effective.

While I agree we need to worry about moisture in buildings I also believe that we need to do this rationally. One of the strengths of Lstiburek and Carmody was the way they tracked water flows. My question regarding the reason we need to apply dampproofing was so that we can develop a rational strategy not a knee jerk reaction that equates water to cancer in buildings.

What is on the other side of the wall? What is the likely head of water being resisted? How frequently is the wall subject to this moisture. If there is not a pressure head of water what are the transport mechanisms that will predominate? Will the expected moisture flow be a problem? Good ventilation will solve a lot of problems.

Admittedly a different material, but when we started putting more membranes around wood buildings to control energy flow the net result was more wood rot. If allowed to dry out periodically wood can accommodate a lot of water.

Moisture does not attack slabs on grade. Concrete likes moisture. If the concrete were to loose all free moisture this would result in a loss of concrete strength. It would also result in increased concrete shrinkage. The problem with slabs on grade is with the coverings applied to the surface of the concrete. It is well documented that the moisture that causes problems with installation of slab coverings comes from the moisture in the concrete and not the moisture under the slab.
Mark Gilligan SE,
Senior Member
Username: mark_gilligan

Post Number: 334
Registered: 10-2007
Posted on Saturday, November 20, 2010 - 03:10 pm:   Edit PostDelete PostPrint Post

I am the Unregistered Guest above.
Anonymous (Unregistered Guest)
Unregistered guest
Posted on Sunday, November 21, 2010 - 12:38 am:   Edit PostDelete PostPrint Post

I don't know about Xypex. We all know that concrete cracks and Xypex becomes one with the concrete - it's not a surface membrane like a peel-and-stick - so what's to stop the water from traversing the concrete if the crack is over 1/6 inch wide which I think is the maximum that the so called"self-healing" Xypex will bridge?
Mark Gilligan SE,
Senior Member
Username: mark_gilligan

Post Number: 335
Registered: 10-2007
Posted on Sunday, November 21, 2010 - 01:42 pm:   Edit PostDelete PostPrint Post

Suggest that 1/16" cracks are not common if concrete is adequately reinforced. You should also ask how tolerant the other system is to cracks. If you had large cracks they could be treated with a slurry of Xypex to the inside of the wall.

While this approach may appear to be too loose to some it may be very pragmatic in some situations. It was stated that the need was for damproofing and it was implied that the interior of the wall was not conditioned. In such instances you may find that Xypex is very effective.

Another consideration is the very cold weather during installation. Ignoring the physical limitations on installation you should ask will the workmen be motivated to doing a careful job or will they just want to get it done. A "better" system poorly installed may not be any better.
John Bunzick, CCS, CCCA, LEED AP
Senior Member
Username: bunzick

Post Number: 1273
Registered: 03-2002
Posted on Tuesday, November 23, 2010 - 11:27 am:   Edit PostDelete PostPrint Post

Go back to the question about the purpose. If there is no basement, and the dampproofing is applied only to the exterior of the foundation wall, what's to keep ground moisture from entering the foundation wall from the non-dampproofed side? Dampproofing such a condition seems a wase of money to me. We have decided to put a membrane of some type at the top of such a wall to keep rising damp from affecting other materials.
Lynn Javoroski CSI CCS LEED® AP SCIP Affiliate
Senior Member
Username: lynn_javoroski

Post Number: 1156
Registered: 07-2002


Posted on Tuesday, November 23, 2010 - 02:18 pm:   Edit PostDelete PostPrint Post

Thank you all. We revisited the overall question this morning. Because the existing site has a lot of rock, we were advised to backfill with aggregate, but drainage tile was not recommended. We've decided that the best solution is to use drain tiles and just give the water the opportunity to move away from our foundation/footing.

By the way, frost is at 3 feet in Iowa. The existing building had no damp proofing, waterproofing, or drain tile.

And we might treat the exposed foundation wall with the same solution as the stone - a silane/siloxane solution - but we haven't determined that exactly yet.

Thanks again and have a blessed Thanksgiving! All y'all are part of what I'm thankful for.
Mark Gilligan SE,
Senior Member
Username: mark_gilligan

Post Number: 337
Registered: 10-2007
Posted on Tuesday, November 23, 2010 - 03:28 pm:   Edit PostDelete PostPrint Post

John

Putting a membrane on top of the foundation wall can void the engineering design. The engineer likely assumes shear is transfered across this surface but you have introduced a slip plane without telling the structural engineer.

I have seen similar details in books on waterproofing but this is not consistent with structural engineering practices.
John Bunzick, CCS, CCCA, LEED AP
Senior Member
Username: bunzick

Post Number: 1275
Registered: 03-2002
Posted on Tuesday, November 23, 2010 - 03:56 pm:   Edit PostDelete PostPrint Post

Mark, Without question the structural engineer needs to be involved in figuring out how to do this. If it is not feasible, though I think there are solutions, I'd still skip the dampproofing.
Jim Sliff
Senior Member
Username: jim_sliff

Post Number: 10
Registered: 08-2010


Posted on Tuesday, November 23, 2010 - 05:12 pm:   Edit PostDelete PostPrint Post

Ditto re skipping dampproofing, which is often "waterproofing" applied under less stringent requirements. When it's lesser-grade asphaltic type the note above is a good point:

"Here in the great northwet, we don't have anything that is considered "dampproofing" -- either it keeps the water out or it doesn't. That asphaltic stuff dissolves after a few years if the soil is acidic enough, and so it isn't worth the bucket it comes in."

Substitute "southwe(s)t" for "northwet"and "alkaline" for "acidic" and you have the L.A. Basin.

I must disagree with the above comment, though, regarding concrete and moisture being great buddies - IMHO that statement can only be applied in specific locations and under specific conditions AND if specific components are used in the concrete mix.

25 years ago we had little problem with alkalinity in concrete, and if foundations or slabs remained slightly damp it was only a floor covering issue (and hit-or-miss wall coating/covering issue, depending on wicking action) that was easily remedied.

We noticed increasing problems from the late-80's-onward and ph testing (combined with several other coatings-specific substrate tests) were performed on nearly every project as the problem accelerated.

The increase in problems (efflorescence) was tracked to a "need" for general cost-reduction in concrete (i.e a lowering of bid pricing) - so the sand sources were changed to some with high (natural) salt content. Some instances were tracked to sand excavated from marine areas in Mexico, trucked north, screened (for size) and included in the mix.

The result was concrete that looked right, was structurally sound - but also "grew hair" when continuously damp. Surface-applied curing agents would mask the problem and became popular - but also prevented coatings or waterproofing membrane adhesion. So another round of tests was required to ensure surface coatings were being applied to concrete and not (in non-technical terms) wax...the curing agent would be removed, coating/waterproofing work completed - and 6 months later efflorescence problems would show up.

So one "cost reduction" knocked over dominos for years, increasing costs on a large number of buildings (I believe there are articles available providing specifics but do not have time to look them up. I'm relating personal experience based on decades of experience with changing conditions in the southwest. Testing that was uncommon 30 years ago is often required nowadays).
Mark Gilligan SE,
Senior Member
Username: mark_gilligan

Post Number: 338
Registered: 10-2007
Posted on Tuesday, November 23, 2010 - 05:39 pm:   Edit PostDelete PostPrint Post

The alkalinity problem is with the covering on the concrete. Concrete is naturaly alkaline. One should consider the advisability of trying to apply something sensitive to alkaline to a natural source of alkaline.

The problem with salt could possibley have been prevented by complying with limits on salt content that are addressed in ACI 318. Even with the efflorescence I would expect the concrete was performing well from a structural perspective.

Even if there is some scenerio where water has a negitive impact on concrete I will suggest that it is so uncommon that it is not worth worryig about.

When efflorescence occurs it is the result of moisture flow and evaporation of the moisture that passed through the concrete.

You would be right to say we have a system problem resulting from the interaction of the different components of the system and I would agree with you. But a statement that water damages concrete is questionable to say the least.
Ron Beard CCS
Senior Member
Username: rm_beard_ccs

Post Number: 361
Registered: 10-2002


Posted on Wednesday, November 24, 2010 - 01:50 am:   Edit PostDelete PostPrint Post

<<...... what's to keep ground moisture from entering the foundation wall from the non-dampproofed side? >>

Dampproofing / waterproofing is intended to prevent the lateral move of water. By reducing the entry of new water into the buildings’ footprint, the amount of water vapor will be reduced. There might still be the presence of ground water under the building, but that will most likely be deep below the slab, but it will not be increased by new water coming in.

<<....a membrane of some type at the top of such a wall to keep rising damp from affecting other materials.>>

I have never heard of a raising damp occurrence in concrete construction. I guess it might be possible but I doubt it. Raising damp is common in old solid [unreinforced, clay/brick] masonry construction which absorbs water and transports liquid water both upwards and laterally.

For centuries, a thin, full-width piece of slate was built into the wall at or below the first floor level to act as a moisture retarder. The slate was an integral part of the masonry construction not what structurally could be a “slip sheet”; hence a structural concern as Mark has expressed. These slates are very visible in older buildings of the 1700's to mid-1900's era masonry buildings. Masonry construction of the era was non-reinforced with each floor level having an additional wythe of brick. I watched an old masonry high-rise demolished in downtown DC [the site just north of where the current Washington Post building is located] which had an 8" thick exterior wall at the top level and with each descending level with an additional 4" wythe. The thickness at the footings were over 4-feet thick and approaching 6-feet in some areas.

[Brian Trimble: If you are still in this group, it would be nice for you to add your 2-cents. Thanx.]
"Fast is good, but accurate is better."
.............Wyatt Earp
Mark Gilligan SE,
Senior Member
Username: mark_gilligan

Post Number: 340
Registered: 10-2007
Posted on Wednesday, November 24, 2010 - 05:19 am:   Edit PostDelete PostPrint Post

If there is a concern about moisture under the footprint of the building put a membrane under the slab. Trying to control it by damproofing on the exterior of the foundation walls is a waste of time. Over time the moisture will flow through the soil under the footing.

When there are concerns about expansive soils we will often extend the perimeter footing a couple of feet to inhibit the flow of moisture between the soil under the building and the soil outside of the building. This addresses the concern about seasonal variations in moisture. We never install a membrane on the perimeter of the footing. This system is effective.

Sound concrete limits the flow of moisture to a level less than that found acceptable for application of flooring on a slab. We are not talking about an active head of water.. This is consistent with the fact that it is the moisture already in the slab that causes problems with flooring application. This resistance to the flow of moisture through concrete is why raising damp is not a problem with concrete buildings.

As Ron Beard points out masonry construction is different. I suggest that this is because the grout is more porous than concrete and because of the small voids that often occur between the masonry and the grout.

Slip sheets (membranes) between concrete pours are often shown in books on waterproofing. I would be interested in how many Architects have shown such details and out of those architects how many specifically pointed this detail out to the structural engineer. Placing the detail in the drawings and expecting the structural engineer to pick it up is not likely to be effective especially because many engineers are reluctant to get involved with waterproofing issues.
Paul Gerber
Senior Member
Username: paulgerber

Post Number: 42
Registered: 04-2010


Posted on Wednesday, November 24, 2010 - 09:41 am:   Edit PostDelete PostPrint Post

Lynn:

Sorry I didn't get a chance to chime in here before seeing that I have a fair bit of experience with COLD & frost here in the great white north. According to the Ontario Building Code we have to design for frost down to 4'-0" below grade, but some engineers would argue that we should really be designing to 5'-0" when building further north of the 49th parallel.

If there are no high water table issues, no excessive hydrostatic pressure AND no basement, then I do not see the need for any dampproofing, let alone waterproofing products on the foundation. Groundwater typically takes the path of least resistance, so if it has a choice between going through soil/backfill and concrete, then the soil/backfill will win almost every time. Even if the water does get inside the foundation walls, concrete SOG construction with a well draining, compacted granular sub-base and base course in combination with a heavy duty (10 mil minimum) underslab vapour retarder should provide all the protection you need to prevent any water from coming up through the slab (again, providing there is not excessive hydrostatic pressure).

It is not uncommon for my firm to detail exactly the systems I have described above without any issue in an environment similar to, or worse than Iowa without any water infiltration issues.

Even with a basement, we typically only specify alsphalt emulsion-based dampproofing; but with that system we spec a HDPE protection board/drainage layer down to the foundation drainage weeping tile system.

Hope this reinforces the decision that has been made and puts your mind at ease for future projects.
Ride it like you stole it!!!

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