Crawl space encapsulation

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Topic Author
eltron
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Joined: Wed Apr 06, 2016 2:25 pm

Crawl space encapsulation

Post by eltron » Mon May 13, 2019 3:09 pm

Hi all,

I'm looking for an unbiased opinion about encapsulating a crawl space.

Just a quick background, I built my house almost 3 years ago and have always had crawlspace issues - specifically flooding in one part of the crawl space. Only a little mold has formed on the rafters, but I'm growing tired of having to be concerned with every hard/extended rain we get and then the BP increase I give myself when I crawl down into the crawlspace.

I've read the reasons why to get a crawl space encapsulated. A few of the reasons:
1. Health reasons. You're essentially allowing unconditioned air come into your house that can cause all kinds of stuff because of mold, debris, whatever air is coming up from under the house.
2. Pests/rodents/insects. Apparently encapsulating will deter most/all of those from coming up from under your house.
3. Better preservation of your house, i.e. avoiding the wood floors from rotting/bowing over time because of said unconditioned air/damp environment under the house.
4. Better heating/electric bills because of conditioned air under your house as opposed to unconditioned air.

These were the main talking points as to why to get it done. However, these were all points made on websites that also install encapsulated crawl spaces. So obviously their opinions are a bit biased.

I did have DryPro come out and give me a quote for the whole 9. Encapsulated crawl space, sump pump install, dehumidifier install, french drain in the crawl space around the perimeter of the problem area, sealed vents, etc. It comes out to just around 10k.

My father is a DIY master and says we can do it all ourselves and, even though I believe him, I'm not keen on the idea of spending my weekend in the crawlspace doing something that DryPro offers with a lifetime guarantee.

I've found online that at least 70% of crawlspaces are an absolute disaster because contractors are very good at skipping corners to something that isn't seen everyday by the home owner.

I obviously want to do this asap if there is legitimate truths to what these websites have said about unconditioned air - I'm very motivated because I have a 3 and 1 year old and I don't want to put them into any kind of harms way.

Anyway, I would love any feedback/opinions on this matter.

Thanks!

jebmke
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Re: Crawl space encapsulation

Post by jebmke » Mon May 13, 2019 3:14 pm

Before doing anything - especially sumps -- you need to figure out where the water is coming from and how to prevent it from getting in in the first place.

We have solved most of our crawl space moisture issue by relocating some down spouts and changing some grading of ground around the perimeter.
When you discover that you are riding a dead horse, the best strategy is to dismount.

Topic Author
eltron
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Re: Crawl space encapsulation

Post by eltron » Mon May 13, 2019 3:26 pm

jebmke wrote:
Mon May 13, 2019 3:14 pm
Before doing anything - especially sumps -- you need to figure out where the water is coming from and how to prevent it from getting in in the first place.

We have solved most of our crawl space moisture issue by relocating some down spouts and changing some grading of ground around the perimeter.
Well that's another issue I didn't point out. We are trying to figure out where this water is coming from. I've had the builder out and they found something was wrong with the foundation drain. They dug a new one, still having the issue.

I was hoping when DryPro came out they'd be more helpful in finding the reason - they were not.

My dad said the same. There's no point in remedying the issue of standing water in the crawlspace if there is still water coming in. It's simply putting some fancy lipstick on a pig, per say.

My thinking is the builder is really bad at grading and our lot wasn't graded properly. A bit perplexed as to how to remedy this issue.

renue74
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Re: Crawl space encapsulation

Post by renue74 » Mon May 13, 2019 3:30 pm

The other poster is right, you need to find the culprit first.

There should be at least a 5% slope . (6" drop over 10' from the house)

This is a good, "safe" slope.

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Bengineer
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Re: Crawl space encapsulation

Post by Bengineer » Mon May 13, 2019 4:16 pm

I do think encapsulating or conditioning a crawl is a good idea, particularly in the humid regions of the country.

I'm with the "figure out where it's coming from" crowd. Go out when it's pouring rain and observe where the water is going. It's not rocket science. It will be obvious when you see the water running and where it pools.

As others have noted, the grade should slope away from the house so the water doesn't run to or pool next to the foundation and the gutters and downspouts should route the water from the roof away from the house. If there's concrete paving next to the house, that joint should be sealed and water should not pool next to the foundation wall.

DIY dad should have some good ideas on resolving the exterior drainage. Get what makes sense done there, observe how that affects the crawl and then form a plan for an encapsulated crawl.

FI4LIFE
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Re: Crawl space encapsulation

Post by FI4LIFE » Mon May 13, 2019 4:49 pm

Agree with the last post. If you understand that water runs downhill, you should be able to figure out if you have a grading issue. Gutter downspouts are another often overlooked culprit.

I doubt contractors cut corners any more on crawl spaces than they do on other foundations. It's likely that more crawlspaces are used in areas with high water tables, predesposing them to more water issues.

likegarden
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Re: Crawl space encapsulation

Post by likegarden » Mon May 13, 2019 5:43 pm

I have a basement in my house, but also had water issues 30 years ago. You need to make sure that water from your roof during steady rains does not find its way into your crawl space. Do you have gutters on your roof, and do the downspouts bring the rain water far away from your crawl space? In my case I had a low area 40 ft away from my house and connected the downspouts to underground corrugated flexible 4 inch black PVC pipes (Home Depot) bringing the rain water there.

Nearly A Moose
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Re: Crawl space encapsulation

Post by Nearly A Moose » Mon May 13, 2019 8:17 pm

Bengineer wrote:
Mon May 13, 2019 4:16 pm
I do think encapsulating or conditioning a crawl is a good idea, particularly in the humid regions of the country.

I'm with the "figure out where it's coming from" crowd. Go out when it's pouring rain and observe where the water is going. It's not rocket science. It will be obvious when you see the water running and where it pools.

As others have noted, the grade should slope away from the house so the water doesn't run to or pool next to the foundation and the gutters and downspouts should route the water from the roof away from the house. If there's concrete paving next to the house, that joint should be sealed and water should not pool next to the foundation wall.

DIY dad should have some good ideas on resolving the exterior drainage. Get what makes sense done there, observe how that affects the crawl and then form a plan for an encapsulated crawl.
Does Dad have any ideas on the cause? Seems like you may need to host him for a beer and a ballgame on TV one day when it’s expected to rain hard.
Pardon typos, I'm probably using my fat thumbs on a tiny phone.

dalbright
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Re: Crawl space encapsulation

Post by dalbright » Mon May 13, 2019 8:33 pm

I'm literally completing this project in my crawl at this moment, with the sump showing up tomorrow and membrane wednesday! I re-routed all of my downspouts and far away from the house cleaned out gutters, adjusted some grading where feasible, added a french drain along the driveway, etc. Those all made huge improvements for us until last week when our neighbor thought he was being nice and re-routed his gutter away from my wifes garden (which would be downhill) and flipped it in a manner that went towards our house. Our house is older with poor insulation originally so i'm adding some as well and then will put down a thick vapor barrier to encapsulate after everything seems to be working as expected. I used a big hammer drill (hammer function) and a clay spade bit to help dig through the clay to be easier to shovel out. I over-build my projects and it was still only around 1000 for a liberty 1/2hp sewage pump (more gph and less likely to jam since can handle solids), levelguard electronic sump switch, zoeller check valve, insulation, septic field pipe (used this instead of corrugated perforated pipe since stronger, larger holes, and can clean out if needed) sump basin, 12mil guardian liner, and a pending radon fan at the end. Adding the radon since will cost me less to just put a fan in than it would to test and people in my area seem to always want to test for it on the home inspection.

Will still be a fair amount of labor and work, but is easy compared to re-roofing my house last month!

carolinaman
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Re: Crawl space encapsulation

Post by carolinaman » Tue May 14, 2019 8:09 am

You need to determine where the water is coming from and then take steps to redirect it. Three likely sources: the lack of a french drain on the exterior foundation, gutter that allows water to flow against the house and the lay of the land directs water toward your house.

Putting a french drain inside the crawl makes no sense to me. It needs to be against the outside of your foundation and you need to seal the foundation wall with tar or similar substance. You should have extensions to your gutters that extend at least 10 feet from the house (buried except endcap) and the water flows away from the house. These 2 items will solve many water problems.

If the slope of your land causes water to flow toward your house, you need to consider ways to redirect the water. This may involve hiring a landscape architect. If you are unsure about this, observe how water flows during and after a hard rain. This may not be a problem for you, but if it is, some landscaping may be necessary.

I did the exterior french drain (very hard work), extended the gutters and put thick plastic on the crawl space floor secure with stakes. I also have a couple of foundation vent fans that I run during warm weather for good ventilation.

If you still have water in crawl after all of the above is done, you likely have an underground source of water that is surfacing in the crawl. In that instance, a sump pump should be able to pump water out.

I know people in the trade whom I trust and respect who consider most crawl space encapsulation as a waste of money. They believe it is an expensive and oversold solution that is often unnecessary. These people prey on homeowners fears and lack of understanding. Moreover, if the encapsulation is not done properly, it will have its own set of problems.

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Sandtrap
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Re: Crawl space encapsulation

Post by Sandtrap » Tue May 14, 2019 8:17 am

Whether remedied with property grading, landscaping, french drains, surface swales, etc, . . . surface water should be redirected as far as possible from the home. If nearer to the property lines on a small lot, all the better.

How high is the crawl space above "grade"?
Lowest level?
Home first floor height above grade?
Difference between average grade of crawl space and highest average grade surrounding the home?
Type of home foundation? (stem walls, piers, etc)

This kind of problem should have a professionally reccomended permanent solution. IE: engineer, etc. (not a company selling services or products).

The issue here is not crawl space encapsulation, but water drainage.
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RickBoglehead
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Re: Crawl space encapsulation

Post by RickBoglehead » Tue May 14, 2019 8:42 am

Make sure you're not blowing out of proportion the fear factor of "unconditioned air". Do you have a forced hot air system with ducts under the house? If not, how is air getting up into the house?

We have a cottage on a lake. The crawlspace is sand, with plastic over it. There is a sump pump. There is a high water table, and this year the water level is at a record high. There is always moist ground. There is ventilation allowing air to pass under the house. Therefore, the unconditioned air is a) exchanged with fresh air and b) is everywhere and breathed in all the time.

Rafters in crawl have had mold on them since the place was built in the 50s. We experience no ill effects.
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unclescrooge
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Re: Crawl space encapsulation

Post by unclescrooge » Tue May 14, 2019 8:57 am

eltron wrote:
Mon May 13, 2019 3:09 pm
Hi all,

I'm looking for an unbiased opinion about encapsulating a crawl space.

Just a quick background, I built my house almost 3 years ago and have always had crawlspace issues - specifically flooding in one part of the crawl space. Only a little mold has formed on the rafters, but I'm growing tired of having to be concerned with every hard/extended rain we get and then the BP increase I give myself when I crawl down into the crawlspace.

I've read the reasons why to get a crawl space encapsulated. A few of the reasons:
1. Health reasons. You're essentially allowing unconditioned air come into your house that can cause all kinds of stuff because of mold, debris, whatever air is coming up from under the house.
2. Pests/rodents/insects. Apparently encapsulating will deter most/all of those from coming up from under your house.
3. Better preservation of your house, i.e. avoiding the wood floors from rotting/bowing over time because of said unconditioned air/damp environment under the house.
4. Better heating/electric bills because of conditioned air under your house as opposed to unconditioned air.

These were the main talking points as to why to get it done. However, these were all points made on websites that also install encapsulated crawl spaces. So obviously their opinions are a bit biased.

I did have DryPro come out and give me a quote for the whole 9. Encapsulated crawl space, sump pump install, dehumidifier install, french drain in the crawl space around the perimeter of the problem area, sealed vents, etc. It comes out to just around 10k.

My father is a DIY master and says we can do it all ourselves and, even though I believe him, I'm not keen on the idea of spending my weekend in the crawlspace doing something that DryPro offers with a lifetime guarantee.

I've found online that at least 70% of crawlspaces are an absolute disaster because contractors are very good at skipping corners to something that isn't seen everyday by the home owner.

I obviously want to do this asap if there is legitimate truths to what these websites have said about unconditioned air - I'm very motivated because I have a 3 and 1 year old and I don't want to put them into any kind of harms way.

Anyway, I would love any feedback/opinions on this matter.

Thanks!
I feel your pain.

I have a very large crawl space, 5ft high, 20x30ft that has very high humidity in SoCal.

The dirt is bone dry but I'm half way down a hill so there is probably the water table issue that I need to fix.

Unfortunately, none of the trades people here have any clue how to deal with humidity issues.

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unclescrooge
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Re: Crawl space encapsulation

Post by unclescrooge » Tue May 14, 2019 9:08 am

Bengineer wrote:
Mon May 13, 2019 4:16 pm
I do think encapsulating or conditioning a crawl is a good idea, particularly in the humid regions of the country.

I'm with the "figure out where it's coming from" crowd. Go out when it's pouring rain and observe where the water is going. It's not rocket science. It will be obvious when you see the water running and where it pools.

As others have noted, the grade should slope away from the house so the water doesn't run to or pool next to the foundation and the gutters and downspouts should route the water from the roof away from the house. If there's concrete paving next to the house, that joint should be sealed and water should not pool next to the foundation wall.

DIY dad should have some good ideas on resolving the exterior drainage. Get what makes sense done there, observe how that affects the crawl and then form a plan for an encapsulated crawl.
What should the joint be sealed with?

I have this issue and I'm thinking of putting in a French drain. We don't really get much rain here in SoCal, but there is a problem with the slope.

This is also the side of the house where I think there is water coming from due to the water table flowing downhill. If I dig up the pavers on that entire side how deep do I need to dig and what treatment do I need to do to prevent moisture coming in?

Humidity in my crawl space is currently 70 percent. It hasn't rained for several days so I don't think it's related to weather. And it's been climbing over the past month. During the wetter months, it was actually below 65 percent.

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unclescrooge
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Re: Crawl space encapsulation

Post by unclescrooge » Tue May 14, 2019 9:10 am

Sandtrap wrote:
Tue May 14, 2019 8:17 am
Whether remedied with property grading, landscaping, french drains, surface swales, etc, . . . surface water should be redirected as far as possible from the home. If nearer to the property lines on a small lot, all the better.

How high is the crawl space above "grade"?
Lowest level?
Home first floor height above grade?
Difference between average grade of crawl space and highest average grade surrounding the home?
Type of home foundation? (stem walls, piers, etc)

This kind of problem should have a professionally reccomended permanent solution. IE: engineer, etc. (not a company selling services or products).

The issue here is not crawl space encapsulation, but water drainage.
What sort of engineer works on foundations? Civil engineer?

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elcadarj
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Re: Crawl space encapsulation

Post by elcadarj » Tue May 14, 2019 9:39 am

The US Department of Energy recommends not only crawlspace encapsulation but also crawlspace conditioning. https://www.energy.gov/sites/prod/files ... 011713.pdf

I have retrofitted my house in the humid southeast. Took care of drainage first: e.g. downspouts all directed to pop-up emitters at least 10 ft downhill of foundation. https://www.homedepot.com/p/NDS-NDS-4-i ... /100153624

Then encapsulated and insulated crawlspace. removed insulation from floor joists and directed conditioned air from HVAC system in crawlspace. As described in research linked above, our house is more comfortable, less pests intruding, no musty smells after multiple days of heavy rains, and energy bills reduced. Worth every penny of about $6k spent about 8 years ago.

megabad
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Re: Crawl space encapsulation

Post by megabad » Tue May 14, 2019 10:52 am

I don’t agree fully with most of that stated reasons for crawlspace encapsulation, sump pump etc but I will say that, if I did it, I would definitely hire it out. Have you ever dug a fence post before? Well now imagine someone putting a ceiling at 3 ft high and chopping your pickaxe / shovel in half. No thanks.

I think for those in developments where the builder has not implemented correct drainage should seek action against the builder if still around. If your house is older though and the crawlspace floods all the time, I guess that is a good case for having the drains installed and encapsulating. Most folks get worried about dampness which I think might be overkill but if you have feet of water under your house, I would do it. The right way to fix it is regrading but in a preplanned neighborhood this opens you up to neighbor issues and gets complicated.

Topic Author
eltron
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Re: Crawl space encapsulation

Post by eltron » Tue May 14, 2019 12:54 pm

Thanks all for the responses. Some very helpful info here.

I live in North Carolina so humidity is a factor here. I agree that the first order of business would be to make a point to figure out where this water is coming from first. I like all the suggestions of where this might be. I've asked my dad to come by the next hard rain that we're supposed to get. I'll get two lawn chairs, a 12 pack and just hang out in the crawl with him until we see something - we'll see how that goes.

After that, I may still consider the encapsulation, but I agree it seems pointless right now if water is still coming in.

Thanks again.

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Re: Crawl space encapsulation

Post by hicabob » Tue May 14, 2019 1:00 pm

eltron wrote:
Tue May 14, 2019 12:54 pm
Thanks all for the responses. Some very helpful info here.

I live in North Carolina so humidity is a factor here. I agree that the first order of business would be to make a point to figure out where this water is coming from first. I like all the suggestions of where this might be. I've asked my dad to come by the next hard rain that we're supposed to get. I'll get two lawn chairs, a 12 pack and just hang out in the crawl with him until we see something - we'll see how that goes.

After that, I may still consider the encapsulation, but I agree it seems pointless right now if water is still coming in.

Thanks again.
With a 12-pack involved the moisture may well be emanating from you two. :shock:

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mhadden1
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Re: Crawl space encapsulation

Post by mhadden1 » Tue May 14, 2019 1:33 pm

Try to find a passive way to make the space under your house well-ventilated and always dry. Route the water away from your house, and encourage enough air to exchange. If you can achieve this, and monitor the situation for a while, I expect you will be satisfied. I hope you can avoid all the pumps and such that can fail and require maintenance.
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Sandtrap
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Re: Crawl space encapsulation

Post by Sandtrap » Tue May 14, 2019 3:29 pm

unclescrooge wrote:
Tue May 14, 2019 9:10 am
Sandtrap wrote:
Tue May 14, 2019 8:17 am
Whether remedied with property grading, landscaping, french drains, surface swales, etc, . . . surface water should be redirected as far as possible from the home. If nearer to the property lines on a small lot, all the better.

How high is the crawl space above "grade"?
Lowest level?
Home first floor height above grade?
Difference between average grade of crawl space and highest average grade surrounding the home?
Type of home foundation? (stem walls, piers, etc)

This kind of problem should have a professionally reccomended permanent solution. IE: engineer, etc. (not a company selling services or products).

The issue here is not crawl space encapsulation, but water drainage.
What sort of engineer works on foundations? Civil engineer?
I have had good results with a "structural engineer" on several projects, 3 commercial and 2 residential.
Not sure if the OP needs one, though.
Wouldn't hurt to ask.
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iasw
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Re: Crawl space encapsulation

Post by iasw » Tue May 14, 2019 4:15 pm

Not sure if this is best practice, but our crawlspace has a perimeter drain, we have sump pumps, and a dehumidifier. The dirt floor has thick plastic and there is something up the sides. I forget. I don't go in there.

We also have good exterior drainage.

The water comes up from the ground, just a high water table.

MindBogler
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Re: Crawl space encapsulation

Post by MindBogler » Tue May 14, 2019 7:27 pm

elcadarj wrote:
Tue May 14, 2019 9:39 am
The US Department of Energy recommends not only crawlspace encapsulation but also crawlspace conditioning. https://www.energy.gov/sites/prod/files ... 011713.pdf

I have retrofitted my house in the humid southeast. Took care of drainage first: e.g. downspouts all directed to pop-up emitters at least 10 ft downhill of foundation. https://www.homedepot.com/p/NDS-NDS-4-i ... /100153624

Then encapsulated and insulated crawlspace. removed insulation from floor joists and directed conditioned air from HVAC system in crawlspace. As described in research linked above, our house is more comfortable, less pests intruding, no musty smells after multiple days of heavy rains, and energy bills reduced. Worth every penny of about $6k spent about 8 years ago.
+1

I had a house built this way, with a conditioned crawl from day 1, down spout bubblers, radon mitigation and such. When I go in the crawl it smells like dry lumber and there are no bugs to speak of.

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unclescrooge
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Re: Crawl space encapsulation

Post by unclescrooge » Wed May 15, 2019 10:16 am

Sandtrap wrote:
Tue May 14, 2019 3:29 pm
unclescrooge wrote:
Tue May 14, 2019 9:10 am
Sandtrap wrote:
Tue May 14, 2019 8:17 am
Whether remedied with property grading, landscaping, french drains, surface swales, etc, . . . surface water should be redirected as far as possible from the home. If nearer to the property lines on a small lot, all the better.

How high is the crawl space above "grade"?
Lowest level?
Home first floor height above grade?
Difference between average grade of crawl space and highest average grade surrounding the home?
Type of home foundation? (stem walls, piers, etc)

This kind of problem should have a professionally reccomended permanent solution. IE: engineer, etc. (not a company selling services or products).

The issue here is not crawl space encapsulation, but water drainage.
What sort of engineer works on foundations? Civil engineer?
I have had good results with a "structural engineer" on several projects, 3 commercial and 2 residential.
Not sure if the OP needs one, though.
Wouldn't hurt to ask.
I got a quote from an engineering company.

They suggested removing the concrete patio, digging a 60ft long trench,6ft deep and lining the foundation of the house with weatherproofing plastic/vynl material to divert water away from the house.

Also suggested putting in 800 gallons of storage tanks, since that water needs to go somewhere, and rather than drain it 100ft down the hill or erode the side of the hill, its better to retain the water and channel it for gardening.

The quote for the entire project was $16,000 :shock:

Does this sound reasonable, in terms of cost and as a solution? I'm in Los Angeles.

Cost includes backfilling but doesn't include making it pretty with pavers or gravel.

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Sandtrap
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Re: Crawl space encapsulation

Post by Sandtrap » Wed May 15, 2019 3:25 pm

unclescrooge wrote:
Wed May 15, 2019 10:16 am
Sandtrap wrote:
Tue May 14, 2019 3:29 pm
unclescrooge wrote:
Tue May 14, 2019 9:10 am
Sandtrap wrote:
Tue May 14, 2019 8:17 am
Whether remedied with property grading, landscaping, french drains, surface swales, etc, . . . surface water should be redirected as far as possible from the home. If nearer to the property lines on a small lot, all the better.

How high is the crawl space above "grade"?
Lowest level?
Home first floor height above grade?
Difference between average grade of crawl space and highest average grade surrounding the home?
Type of home foundation? (stem walls, piers, etc)

This kind of problem should have a professionally reccomended permanent solution. IE: engineer, etc. (not a company selling services or products).

The issue here is not crawl space encapsulation, but water drainage.
What sort of engineer works on foundations? Civil engineer?
I have had good results with a "structural engineer" on several projects, 3 commercial and 2 residential.
Not sure if the OP needs one, though.
Wouldn't hurt to ask.
I got a quote from an engineering company.

They suggested removing the concrete patio, digging a 60ft long trench,6ft deep and lining the foundation of the house with weatherproofing plastic/vynl material to divert water away from the house.

Also suggested putting in 800 gallons of storage tanks, since that water needs to go somewhere, and rather than drain it 100ft down the hill or erode the side of the hill, its better to retain the water and channel it for gardening.

The quote for the entire project was $16,000 :shock:

Does this sound reasonable, in terms of cost and as a solution? I'm in Los Angeles.

Cost includes backfilling but doesn't include making it pretty with pavers or gravel.
I had a 32 unit apartment building that had foundation settling issues over many decades which cause the corner concrete blocks in some areas to shift. 2 Engineering companies had elaborate solutions $$$$ which were guaranteed to work. A masonry structural retaining wall company I knew had some creative ideas to divert heavy rainwater flow away from the buildings that were "affordable". Then one day, I spoke to a concrete contractor friend who was on one of my other projects and he suggested regrading the grounds, concrete slab pours over a few sloped areas, and wide sidewalks around the perimeter of all 3 buildings. I ended up using a combination of ideas from my friend's retaining wall company and also the concrete contractor. Problem 90% solved at a fraction of the cost of the ideas from the engineering companies.
Sometimes it pays to get input from a variety of contractors on how they might solve a problem in the most practical and affordable way. I've solved many a construction project problem this way.
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Saving$
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Re: Crawl space encapsulation

Post by Saving$ » Wed May 15, 2019 7:39 pm

eltron wrote:
Mon May 13, 2019 3:26 pm
jebmke wrote:
Mon May 13, 2019 3:14 pm
Before doing anything - especially sumps -- you need to figure out where the water is coming from and how to prevent it from getting in in the first place.

We have solved most of our crawl space moisture issue by relocating some down spouts and changing some grading of ground around the perimeter.
Well that's another issue I didn't point out. We are trying to figure out where this water is coming from. I've had the builder out and they found something was wrong with the foundation drain. They dug a new one, still having the issue.

I was hoping when DryPro came out they'd be more helpful in finding the reason - they were not.

My dad said the same. There's no point in remedying the issue of standing water in the crawlspace if there is still water coming in. It's simply putting some fancy lipstick on a pig, per say.

My thinking is the builder is really bad at grading and our lot wasn't graded properly. A bit perplexed as to how to remedy this issue.
This. You need to figure out where the water is coming from.
- Need a foundation drain around the EXTERIOR. It needs to drain. Put a "cleanout" at the foundation drain high point and send water through it during a dry spell to be sure it comes out the other end. If it goes in your crawlspace you are closer to identifying the problem.
- You may need to dig a trench around your house and apply waterproofing.
- Check grades, downspouts, etc.

Once you figure out how the water is getting in, you can keep it out. AFTER you keep the water out, yes you should encapsulate your crawl space. For all the reasons you read about.

GAAP
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Re: Crawl space encapsulation

Post by GAAP » Thu May 16, 2019 10:34 am

What is the water table level? My crawlspace can be as little as a foot above the water table at some times in the year. There's not much point in grading, building a drain system, etc. if the water will just ooze out of the soil anyway...
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marti038
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Re: Crawl space encapsulation

Post by marti038 » Thu May 16, 2019 11:22 am

I just encapsulated mine over the winter. Start to finish took about 3 months and I spent about $3000 to put in french drains and encapsulate. The crawl space at my home was about 1700 square feet and I have and average of about 4' of room between the ground and the bottom floor of the house.

The primary benefit we've noticed is smell. The house smells fresher all the time. Second, because we sealed the vents the air temperature in the crawl space has been about 10 degrees warmer (in the winter at least). I haven't calculated it, but it can't be hurting our heating and cooling costs in the rest of the house. It's also nice to know the chipmunks can't come and go from below my house as they please.

If I had to do it over again, I would absolutely do it myself, and I would do it in the winter. I think it may have been problematic to try and do all that in the hot, humid, Alabama summer.

I used crawlspacerepair.com for my materials and have no complaints. If you do it yourself, go ahead and get some good kneepads and a very sharp box cutter or exacto knife. The biggest headache was having to cut in the material around pipes, wires, and electrical boxes.

Good luck.

dalbright
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Re: Crawl space encapsulation

Post by dalbright » Thu May 16, 2019 12:39 pm

marti038 wrote:
Thu May 16, 2019 11:22 am
I just encapsulated mine over the winter. Start to finish took about 3 months and I spent about $3000 to put in french drains and encapsulate. The crawl space at my home was about 1700 square feet and I have and average of about 4' of room between the ground and the bottom floor of the house.

The primary benefit we've noticed is smell. The house smells fresher all the time. Second, because we sealed the vents the air temperature in the crawl space has been about 10 degrees warmer (in the winter at least). I haven't calculated it, but it can't be hurting our heating and cooling costs in the rest of the house. It's also nice to know the chipmunks can't come and go from below my house as they please.

If I had to do it over again, I would absolutely do it myself, and I would do it in the winter. I think it may have been problematic to try and do all that in the hot, humid, Alabama summer.

I used crawlspacerepair.com for my materials and have no complaints. If you do it yourself, go ahead and get some good kneepads and a very sharp box cutter or exacto knife. The biggest headache was having to cut in the material around pipes, wires, and electrical boxes.

Good luck.
I just received my membrane from crawlspacerepair.com yesterday!

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Re: Crawl space encapsulation

Post by ddurrett896 » Thu May 16, 2019 1:16 pm

eltron wrote:
Tue May 14, 2019 12:54 pm
Thanks all for the responses. Some very helpful info here.

I live in North Carolina so humidity is a factor here.
I live in southern VA and feel your pain with humidity. House is 46 years old, with no vapor barrier and bone dry. Termite company that inspects each year sells vapor barrier install and doesn't even recommend.

Fix the water like you said, then go from there.

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Re: Crawl space encapsulation

Post by mhadden1 » Thu May 16, 2019 2:00 pm

unclescrooge wrote:
Wed May 15, 2019 10:16 am

The quote for the entire project was $16,000 :shock:

Does this sound reasonable, in terms of cost and as a solution? I'm in Los Angeles.
The internet tells me that Los Angeles often gets less than 20 inches of rain a year. I just have to think that a non-nuclear solution for water under the house is in reach. I realize, though, that the devil is in the particular details.

Another post recommended created hardspace swales to make water run away from the house. This could be a pretty inexpensive and attractive DIY - if pavers were insufficient they could always be taken up and re-used at the end, after the nuclear blast.

Good luck!
Oh I can't, can I? That's what they said to Thomas Edison, mighty inventor, Thomas Lindberg, mighty flyer,and Thomas Shefsky, mighty like a rose.

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unclescrooge
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Re: Crawl space encapsulation

Post by unclescrooge » Thu May 16, 2019 2:57 pm

mhadden1 wrote:
Thu May 16, 2019 2:00 pm
unclescrooge wrote:
Wed May 15, 2019 10:16 am

The quote for the entire project was $16,000 :shock:

Does this sound reasonable, in terms of cost and as a solution? I'm in Los Angeles.
The internet tells me that Los Angeles often gets less than 20 inches of rain a year. I just have to think that a non-nuclear solution for water under the house is in reach. I realize, though, that the devil is in the particular details.

Another post recommended created hardspace swales to make water run away from the house. This could be a pretty inexpensive and attractive DIY - if pavers were insufficient they could always be taken up and re-used at the end, after the nuclear blast.

Good luck!
It's not rain water coming into the crawl space. It's probably the over watering of the gardens from 20 homes higher than me finding it's way down to me.
I know this because the humidity is higher in the dry months and lower in the wet ones.

We didn't have pavers, but a large concrete patio.

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unclescrooge
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Re: Crawl space encapsulation

Post by unclescrooge » Thu May 16, 2019 2:58 pm

Sandtrap wrote:
Wed May 15, 2019 3:25 pm
unclescrooge wrote:
Wed May 15, 2019 10:16 am
Sandtrap wrote:
Tue May 14, 2019 3:29 pm
unclescrooge wrote:
Tue May 14, 2019 9:10 am
Sandtrap wrote:
Tue May 14, 2019 8:17 am
Whether remedied with property grading, landscaping, french drains, surface swales, etc, . . . surface water should be redirected as far as possible from the home. If nearer to the property lines on a small lot, all the better.

How high is the crawl space above "grade"?
Lowest level?
Home first floor height above grade?
Difference between average grade of crawl space and highest average grade surrounding the home?
Type of home foundation? (stem walls, piers, etc)

This kind of problem should have a professionally reccomended permanent solution. IE: engineer, etc. (not a company selling services or products).

The issue here is not crawl space encapsulation, but water drainage.
What sort of engineer works on foundations? Civil engineer?
I have had good results with a "structural engineer" on several projects, 3 commercial and 2 residential.
Not sure if the OP needs one, though.
Wouldn't hurt to ask.
I got a quote from an engineering company.

They suggested removing the concrete patio, digging a 60ft long trench,6ft deep and lining the foundation of the house with weatherproofing plastic/vynl material to divert water away from the house.

Also suggested putting in 800 gallons of storage tanks, since that water needs to go somewhere, and rather than drain it 100ft down the hill or erode the side of the hill, its better to retain the water and channel it for gardening.

The quote for the entire project was $16,000 :shock:

Does this sound reasonable, in terms of cost and as a solution? I'm in Los Angeles.

Cost includes backfilling but doesn't include making it pretty with pavers or gravel.
I had a 32 unit apartment building that had foundation settling issues over many decades which cause the corner concrete blocks in some areas to shift. 2 Engineering companies had elaborate solutions $$$$ which were guaranteed to work. A masonry structural retaining wall company I knew had some creative ideas to divert heavy rainwater flow away from the buildings that were "affordable". Then one day, I spoke to a concrete contractor friend who was on one of my other projects and he suggested regrading the grounds, concrete slab pours over a few sloped areas, and wide sidewalks around the perimeter of all 3 buildings. I ended up using a combination of ideas from my friend's retaining wall company and also the concrete contractor. Problem 90% solved at a fraction of the cost of the ideas from the engineering companies.
Sometimes it pays to get input from a variety of contractors on how they might solve a problem in the most practical and affordable way. I've solved many a construction project problem this way.
Makes sense. I'm get more quotes.👍

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marti038
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Re: Crawl space encapsulation

Post by marti038 » Thu May 16, 2019 3:10 pm

marti038 wrote:
Thu May 16, 2019 11:22 am
I just encapsulated mine over the winter. Start to finish took about 3 months and I spent about $3000 to put in french drains and encapsulate. The crawl space at my home was about 1700 square feet and I have and average of about 4' of room between the ground and the bottom floor of the house.

The primary benefit we've noticed is smell. The house smells fresher all the time. Second, because we sealed the vents the air temperature in the crawl space has been about 10 degrees warmer (in the winter at least). I haven't calculated it, but it can't be hurting our heating and cooling costs in the rest of the house. It's also nice to know the chipmunks can't come and go from below my house as they please.

If I had to do it over again, I would absolutely do it myself, and I would do it in the winter. I think it may have been problematic to try and do all that in the hot, humid, Alabama summer.

I used crawlspacerepair.com for my materials and have no complaints. If you do it yourself, go ahead and get some good kneepads and a very sharp box cutter or exacto knife. The biggest headache was having to cut in the material around pipes, wires, and electrical boxes.

Good luck.
I should add that we bought the house "as is" 3 years ago and it had water running through the crawl space during and after every rain event. The first year I installed french drains around the exterior walls in the crawl space (I would have had to dig some extremely deep trenches to put them on the outside) which drain out into the yard. This caught all the water that had been coming in under the foundation previously, but it was quite a task. I graded all the soil in the crawlspace to run outward toward the drains. Also, digging the drain trenches on your knees in a tight space puts some miles on your back and knees. Finally, hauling in 4 yards of gravel so the water could drain properly took some effort. The french drains took 2 months of weekends and evenings. Total cost was about $350 + time.

Stage 2 was catching all the water from my downspouts and directing it away from the house. That water drains out into a concrete storm drain between my neighbor and myself. This was about a 2 week job and was only a couple hundred bucks in PVC materials. Once I did this the french drains went dry and have been dry ever since.

After step 1 & 2 I waited about a year and a half. We had some other projects going on in our fixer upper, so I took this time to test and observe the water drainage measures we had taken. After some very heavy rains (like 3-5 inches in a day) I was satisfied that it would take some pretty significant weather for water to get past my french drains and downspout drains.

I elected to put 2" thick rigid foam insulation on the exterior walls, but will admit that spray foam would have been much easier. You have to seal all the gaps between the foam and the walls and between each sheet. This took a lot of liquid nails and probably a dozen cans of great stuff. I also found the best way to adhere the foam to the walls was to start with liquid nails on each sheet, followed with several tapcon screws.

After the foam was in I but down a layer of felt material to protect the liner and to give me something to sit on that wasn't just bare dirt. I hung 12mil membrane on the walls and put 20mil on the floor. 20mil is probably overkill unless you plan to also host dance parties in your crawlspace.

After installation, I opened two supply vents to the crawl space to help with humidity (this is also code). It is much better than it used to be, but as temps and humidity rise outside, I've noticed it increasing in the crawl space too (as high as 70% this last weekend :( ). I may have to break down and buy a dehumidifier if I can't mitigate that.

The overall project cost, not including the french drains and downspout drains was about $2500.00. The insulation was much more costly ($30/sheet x 16 sheets) and more time consuming than I expected, but I was certain I didn't want to have a condensation issue later and have to take all that liner down and reinstall it.

We had a bid from the previous homeowner to install a small section of french drain, grade the soil, and install a dehumidifier (no liner, no insulation, and no exterior drains) for about $10k. We leveraged this to lower the price of the house when we bought it. I chose to do the work myself because I was confident I could do it well and save a lot of money. Being 37 doesn't hurt either. I would not want to take something like this on in my latter years.

P.S. - Momma will probably get tired of you mulling around under the house while she watches the little ones. Plan to do some of this at night, bit by bit. This doesn't sound compatible with your desire for haste.

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gasdoc
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Re: Crawl space encapsulation

Post by gasdoc » Fri May 17, 2019 10:38 am

marti038 wrote:
Thu May 16, 2019 3:10 pm
marti038 wrote:
Thu May 16, 2019 11:22 am
I just encapsulated mine over the winter. Start to finish took about 3 months and I spent about $3000 to put in french drains and encapsulate. The crawl space at my home was about 1700 square feet and I have and average of about 4' of room between the ground and the bottom floor of the house.

The primary benefit we've noticed is smell. The house smells fresher all the time. Second, because we sealed the vents the air temperature in the crawl space has been about 10 degrees warmer (in the winter at least). I haven't calculated it, but it can't be hurting our heating and cooling costs in the rest of the house. It's also nice to know the chipmunks can't come and go from below my house as they please.

If I had to do it over again, I would absolutely do it myself, and I would do it in the winter. I think it may have been problematic to try and do all that in the hot, humid, Alabama summer.

I used crawlspacerepair.com for my materials and have no complaints. If you do it yourself, go ahead and get some good kneepads and a very sharp box cutter or exacto knife. The biggest headache was having to cut in the material around pipes, wires, and electrical boxes.

Good luck.
I should add that we bought the house "as is" 3 years ago and it had water running through the crawl space during and after every rain event. The first year I installed french drains around the exterior walls in the crawl space (I would have had to dig some extremely deep trenches to put them on the outside) which drain out into the yard. This caught all the water that had been coming in under the foundation previously, but it was quite a task. I graded all the soil in the crawlspace to run outward toward the drains. Also, digging the drain trenches on your knees in a tight space puts some miles on your back and knees. Finally, hauling in 4 yards of gravel so the water could drain properly took some effort. The french drains took 2 months of weekends and evenings. Total cost was about $350 + time.

Stage 2 was catching all the water from my downspouts and directing it away from the house. That water drains out into a concrete storm drain between my neighbor and myself. This was about a 2 week job and was only a couple hundred bucks in PVC materials. Once I did this the french drains went dry and have been dry ever since.

After step 1 & 2 I waited about a year and a half. We had some other projects going on in our fixer upper, so I took this time to test and observe the water drainage measures we had taken. After some very heavy rains (like 3-5 inches in a day) I was satisfied that it would take some pretty significant weather for water to get past my french drains and downspout drains.

I elected to put 2" thick rigid foam insulation on the exterior walls, but will admit that spray foam would have been much easier. You have to seal all the gaps between the foam and the walls and between each sheet. This took a lot of liquid nails and probably a dozen cans of great stuff. I also found the best way to adhere the foam to the walls was to start with liquid nails on each sheet, followed with several tapcon screws.

After the foam was in I but down a layer of felt material to protect the liner and to give me something to sit on that wasn't just bare dirt. I hung 12mil membrane on the walls and put 20mil on the floor. 20mil is probably overkill unless you plan to also host dance parties in your crawlspace.

After installation, I opened two supply vents to the crawl space to help with humidity (this is also code). It is much better than it used to be, but as temps and humidity rise outside, I've noticed it increasing in the crawl space too (as high as 70% this last weekend :( ). I may have to break down and buy a dehumidifier if I can't mitigate that.

The overall project cost, not including the french drains and downspout drains was about $2500.00. The insulation was much more costly ($30/sheet x 16 sheets) and more time consuming than I expected, but I was certain I didn't want to have a condensation issue later and have to take all that liner down and reinstall it.

We had a bid from the previous homeowner to install a small section of french drain, grade the soil, and install a dehumidifier (no liner, no insulation, and no exterior drains) for about $10k. We leveraged this to lower the price of the house when we bought it. I chose to do the work myself because I was confident I could do it well and save a lot of money. Being 37 doesn't hurt either. I would not want to take something like this on in my latter years.

P.S. - Momma will probably get tired of you mulling around under the house while she watches the little ones. Plan to do some of this at night, bit by bit. This doesn't sound compatible with your desire for haste.
I'd go ahead and put in a dehumidifier and seal/insulate the vents. Then you can achieve low humidity and take advantage of all that new insulation. We have a completely clean, dehumidified, sealed crawlspace that we open to change the dehumidifier filter every three months. It is great.

gasdoc

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marti038
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Re: Crawl space encapsulation

Post by marti038 » Fri May 17, 2019 1:33 pm

gasdoc wrote:
Fri May 17, 2019 10:38 am


I'd go ahead and put in a dehumidifier and seal/insulate the vents. Then you can achieve low humidity and take advantage of all that new insulation. We have a completely clean, dehumidified, sealed crawlspace that we open to change the dehumidifier filter every three months. It is great.

gasdoc
I should have been more clear that the vents I opened are supply vents from the HVAC system. Other than access, no part of the crawl space is open to the outside anymore.

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gasdoc
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Re: Crawl space encapsulation

Post by gasdoc » Sat May 18, 2019 9:37 am

marti038 wrote:
Fri May 17, 2019 1:33 pm
gasdoc wrote:
Fri May 17, 2019 10:38 am


I'd go ahead and put in a dehumidifier and seal/insulate the vents. Then you can achieve low humidity and take advantage of all that new insulation. We have a completely clean, dehumidified, sealed crawlspace that we open to change the dehumidifier filter every three months. It is great.

gasdoc
I should have been more clear that the vents I opened are supply vents from the HVAC system. Other than access, no part of the crawl space is open to the outside anymore.
Now that makes sense. :happy

gasdoc

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marti038
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Re: Crawl space encapsulation

Post by marti038 » Wed Jul 17, 2019 9:46 am

As an update, I did get a dehumidifier in May after humidity levels kept pushing above 70%. I was afraid the dehumidifier would use a lot of electricity, but I haven't noticed any significant increase in our bill. It's pretty much in line with last summer.

I haven't measured it carefully, but I suspect that having insulated and sealed the crawl space has helped reduce the amount of time our A/C runs. It is now a steady 70 degrees with 40%-50% humidity under the house. I've been very pleased with the overall results of encapsulation.

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gasdoc
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Re: Crawl space encapsulation

Post by gasdoc » Wed Jul 17, 2019 3:52 pm

marti038 wrote:
Wed Jul 17, 2019 9:46 am
As an update, I did get a dehumidifier in May after humidity levels kept pushing above 70%. I was afraid the dehumidifier would use a lot of electricity, but I haven't noticed any significant increase in our bill. It's pretty much in line with last summer.

I haven't measured it carefully, but I suspect that having insulated and sealed the crawl space has helped reduce the amount of time our A/C runs. It is now a steady 70 degrees with 40%-50% humidity under the house. I've been very pleased with the overall results of encapsulation.
That is very similar to our experience. I will add though that we have had a problem with field mice getting into the crawl space now that it has become such a nice place with regards to temperature and humidity.

gasdoc

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