Crawl space encapsulation with or without insulation?

[Rich1028]

CRAWL SPACE ENCAPSULATION WITH OR WITHOUT INSULATION?

for our house it is around $10,000 without insulation,or $12,000 with insulation.
just wondering what if any savings of heat,or air conditioning we will save buy going with the insulation.

the type of insulation I am asking about is the kind that they put over the brick walls,before they put the vapor barrier over them

 

[Copymutt]

Depends on ground moisture. Even here in drought stricken Co. Vapor barrier goes on the dirt.
Whats your water table? Expecting sump pump?
If dry not much benefit.
If you insulate under the floor, will you worry about freezing water lines below the insulation?

 

[Leaflessshadetree]

I had the walls and rim joist of my crawlspace spray foamed.
I can feel the difference in the room above it, especially in the winter.

 

[Notgrownup]

I was going to do it but opted to just seal my vents and install a dehumidifier and leave the 80% vapor barrier, my humidity has been 55% since. $1500.
Way different climate than you though but my floor did feel warmer this winter if you insulated your walls it would give you more effective heating results.

 

[finn]

I put a visquene vapor barrier on the sand floor, 2” blue foam on the block walls, and had the rim joists spray foamed on our guest house.

The house is very energy efficient, and the floors are relatively warm in winter, even though the only heat in the crawl is leakage from the furnace ducts, and radiation downward from the room floors.

Well worth the minimal investment. The previous owner constantly fought freezing pipes. Not an issue with it now, even though we cut the heat back to 50 degrees in the winter, on below zero days, when the house is unoccupied.

 

[Rich1028]

Depends on ground moisture. Even here in drought stricken Co. Vapor barrier goes on the dirt.
Whats your water table? Expecting sump pump?
If dry not much benefit.
If you insulate under the floor, will you worry about freezing water lines below the insulation?

2 sump pumps,one in old end of house,and one in newer side of house.

 

[fsae0607]

I remember a similar discussion here a few months back. Another fellow GJ'er that also lived in California mentioned that crawl spaces need to "breathe" and that insulation would trap in moisture and cause rot in your structure.

I have a crawl space without any insulation or vapor barrier. No mold issues. Also, the floor isn't too bad in the winter. I have the original oak floor from '56 when my house was built.

Not sure about back east where the OP is, though.

 

[joey1320]

I would try contacting Tanner Flowers --

I have spoken with him about his work and the guy is super cool and accessible. His work speaks for itself.

 

[Rich1028]

I would try contacting Tanner Flowers --

I have spoken with him about his work and the guy is super cool and accessible. His work speaks for itself.

they do not cover Michigan

 

[Mogana]

Thanks for the all the contribution......

 

[50pascals]

The idea with encapsulating the crawl space is you bring it fully "inside" the home. Thus, do the insulation now.

Would you ask if you should insulate a porch that you were now going to enclose and turn into living space? No, you would automatically insulate it. This is the same scenario, but people minimize it in their heads because it's "down there" and they never see it.

 

[b-boy]

I have a cistern and a crawlspace under half my house. I had spray foam added and they put down a vapor barrier on the floor/walls. I added a dehumidifier. I have a temp/humidity sensor in the area.

Humidity stays in the 35% range (It was in the 70%s), and the temp never goes below 60F, even in February (I'm in buffalo, NY). That's a good thing, because some yahoo ran an uninsulated 3/4" copper heating pipe through the area.

Total cost was about $3.5K.

 

[glentre]

I have lived in houses with crawl spaces and houses with slabs. Crawl spaces are nothing but constant problems with moisture, critters, insects, and difficulty servicing anything on your belly. Our current house is built on an elevated insulated slab, much like many of our garages are constructed. Crawl space problems gone........ best decision I ever made when designing the house. I understand some home designs make it difficult to go with a slab but if possible, an insulated slab, IMHO would be the best choice.

Our neighbor has a crawl space but his contractor laid down a vapor barrier and poured 3" of concrete on it and he has no moisture problems and doesn't need to spend money year after year to keep the space conditioned.

Glen

 

[mikec35]

Can't advise about the insulation but just so you can get an idea of what others have paid: I had my crawlspace encapsulated. They removed all existing fiberglass insulation under the floors, sprayed all the wood with a mold inhibitor, installed new insulation under the floors, installed trench drains going to a commercial sump pump, sealed the vents and used 30mil vapor barrier on the floor and walls. They also installed a commercial dehumidifier plus ran a new circuit to it. Cost was $9800. They did not insulate the walls. I am in NC so we don't have the cold you have up North but we typically have warmer weather.

My house had a lot of moisture in the crawlspace. The previous owner disclosed that "occasionally water get's under the house." Based on what it looked like it think they should have said it's occasionally dry under the house. Fortunately the seller paid for the work...

 

[jbwilkins]

Another fellow GJ'er that also lived in California mentioned that crawl spaces need to "breathe" and that insulation would trap in moisture and cause rot in your structure.

It all depends on how tight the entire structure is, most new construction with a crawl is conditioned.

One thing to be aware of is Radon levels in your area. If you live in a location with high levels you want to make sure that the enclapsated crawl has a Radon mitigation system.

 

[GRivera]

My house has a partial crawl space around 600 sf. I have it sealed with 15 mil on floor and up walls. 2" foam board insulation on walls and rim-joists spray foamed. Also have a small HVAC vent into the space to condition it. I've been in the space in the middle of winter and it is very comfortable. And, it keeps the hardwood floor above the same temp as the rest of the house - used to be cold before.

 

[ddurrett896]

My house has a partial crawl space around 600 sf. I have it sealed with 15 mil on floor and up walls. 2" foam board insulation on walls and rim-joists spray foamed. Also have a small HVAC vent into the space to condition it. I've been in the space in the middle of winter and it is very comfortable. And, it keeps the hardwood floor above the same temp as the rest of the house - used to be cold before.

I'm in VA - kinda close to you. Do you have do termite inspections up there? If so, how the process with the rim joist sprayed? Thanks!

 

[Diesel Dan]

CRAWL SPACE ENCAPSULATION WITH OR WITHOUT INSULATION?

for our house it is around $10,000 without insulation,or $12,000 with insulation.
just wondering what if any savings of heat,or air conditioning we will save buy going with the insulation.

the type of insulation I am asking about is the kind that they put over the brick walls,before they put the vapor barrier over them

IMO, treat a crawl space like a basement.
Intercept the moisture and cold on the outside of the walls.
Insulation, are you referring to ridged foam board?

I've helped with some crawls and basements in the Saginaw valley years ago. Best thing is dig down to the footer, perimeter drain tile and work your way up from there.

If I ever built on a crawl it would basically be a short basement. Would have proper vapor barrier under a thin concrete slab so I could scoot around on a creeper if need be. Plus I'd make it a conditioned space so no exterior vents.

 

[3onthetree]

1.5 year-old thread resurrected by a spammer

 

[Diesel Dan]

1.5 year-old thread resurrected by a spammer

So it is.