I have a question, actually I’m trying to identify my problem so I can solve it. My home was built with a full 8′ basement under it. There was an existing garge, the house was built 14 feet away from that. After the house foundation was in, there was a crawl space put in to connect the house to the garage and it is approximately 7 ft wide by 14 ft long. Crawl space was dug out completely, walls poured, plastic layed down, and a foot or two of stone put in. Floor in crawl space is made out of 2 X 12 with 12″ of insulation between. The room above the crawl space acts as a laundry room, and it has always been a cold room, not unusual for it to be 10 degree’s or more lower than the rest of the house. When the rest of the home is 70 degree’s, the laundry room is 60 degree’s, but if you check the temperature right in front of the dryer, temps go down at least another 5 degree’s. On extremely cold nights it can dip even more. I’m not sure if I should blame the coldness on the crawl space or the dryer vent or on both? Crawl space floor is ceramic tile. The crawl space has no vents but the floor is insulated with 12 inches of fiberglass. There is a heater vent that goes thru the insulation out into the crawl space. Any idea’s anyone? I was not sure if the crawl space should have had a vent or two in it? I was not sure if there was any type of special vent for the dryer that is insulated, can’t find one locally. Clearly the dryer vent has something to do with the coldness though, just wasn’t sure what I could do about that. Typical vent on the dryer, one that goes thru the wall and has the “flap” on it that opens when dryer is on. Thanks in advance for any help you can offer….
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Do I understand correctly that the crawlspace is heated??
Is the laundry room heated directly??
Given the info given, it does sound like the problem is the exhaust vent on the dryer. I'm not sure what products there are to deal with this, but I'll bet there is something.
Rich Beckman
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Thanks for replying Rich. I'm sorry I wasn't clear. No, the crawl space itself isn't heated. That is sealed up entirely with no access whatsoever. The room that was built above it that connects the house to the garage is heated and part of the house.
The dryer vent is definately part of the problem, I've stopped at a couple appliance stores and inquired about ways of dealing with that, but they tell me the only vent they know of is just that cheap flexible type hose that connects from the back of the dryer to the vent that passes through the wall. On the outside of the house all there is, is the cheap tin flap so you can see where it can let a ton of cold air in. I figure I can't be the only one with this problem, there must be something a little better on the market?
On the crawl space itself, since the entire ceramic tile floor in that room is always pretty cold, I was just wondering if we did all we could to eliminate any problems or if I could do anything more? I've seen vents put in crawl spaces before but I was not sure if they should have been installed in this application? Or perhaps I thought I should cut out part of the concrete wall dividing the crawl space to the basement, although I have read posts where folks are having trouble with the crawl space making their entire basement cold.
I'm just trying to look for more ways to make the house more comfortable and save a bit of energy along the way.....Thanks again! Mark
This might work for the dryer vent:http://www.energyfederation.org/consumer/default.php/cPath/86_742_110In your first post you wrote:"There is a heater vent that goes thru the insulation out into the crawl space."What does that mean??Is the crawl space accessible??Is it open to the basement??
Rich BeckmanThis signature line intentionally left blank.
Hi Rich,
I'm very sorry, I couldn't have messed that first post up more if I tryed. I think I must have changed a sentence or something and forgot to proofread! Plus I type faster than I think! The crawl space, which is under the laundry room, is completely sealed and there is no access at all. It is not open to the basement, nor are there any vents in it. The dryer vent goes out through the wall above ground level. The floor in the entire room stays very cold, but the closer you get to the dryer, the colder it gets. I know the dryer vent is the cause of a lot of the coldness, but I've always wondered if the crawl space was insulated enough or if there was also more I could do with that.
The link you sent me with the Heartland dryer vent is perfect! That's exactly what I need. Around me, all anyone carries is the cheap tin vent that goes through the wall. A sealed vent, made out of plastic material will surely not leak as much air as the one I have. Thanks so much for sending that! I will order one right away....
This is by far the best message board I've found on the computer, I'll try much harder to be more clear on my posts so I don't waste everyone's time. I've had so many things happen over the years without knowing where to go for advice and I really appreciate the help everyone offers. Thank you again Rich.
Mark
Why connect the house to the garage with a crawlspace?
Did Jeffrey Dahmer influence the design?
I did the walls myself BZbuilder, and back when this was done, pretty much did what was asked of me by the builder and didn't question anything. However, I'm wondering, what other options would I of had? The laundry room above was to be heated, you couldn't put a room like that on a slab with no walls under it when it is tied to the house and garage would you? Or are you thinking it should have been completely filled in with a concrete floor poured on top?
I am wishing now that we had left at the very least an access hole between the house and crawl space, but with no pipes or anything in there to give a guy troubles I thought at the time we were doing the correct thing and didn't question it.
Mark
"This is by far the best message board I've found on the computer,"Welcome to Breaktime.Ask for access to the Tavern and then we can give you "advice" on any subject you can think of (whether you want it or not!).
Back to the thread:Generally, a completely sealed up crawl is a bad idea. Also, I believe code forbids having a space like that and not having access.I think you would be better off if the walls to the crawl were insulated instead of the crawl "ceiling" and then run a heat duct into it. If it is a small enough space and the "ceiling" is sealed well, then it might be necessary to put in a cold air return so the heat would actually enter the space.This opinion may well be worth what you are paying for it.Rich BeckmanThis signature line intentionally left blank.
Looking back now Rich, I do wish we'd have run heat out there and heated the underground crawl space, and also left an access hole through the basement wall as well. I believe at the time the house was built, the carpenter used the logic that the ground temps were 50 degree's, therefore putting insulation in the floor and one heat duct outlet in the room above should have been quite enough to take care of things.
In hindsight heating the crawl space now sounds good, but not real practical anymore. The crawl space was filled in with a couple feet of stone, and now it has 2' X 12" joists across it every 16" and a floor on top of that. You've given me an idea though, perhaps it would help if I dug down on the outside of the walls and at the least put a couple inches of foam along the crawl space walls.
Mark
Found a photo! This probably won't tell you guys a whole lot, but at the very least you may pick up something I'm missing.
When the house was built, we did all the foundation walls, but not the crawl space walls right away. The carpenters were not sure at the time exactly how or where they wanted to tie the walls & roof in with the existing garage. So, we did the home foundation, and put the crawl space walls in afterwards. You can see in the attachment where I drew the line, this is approximately where the house foundation (8') walls are. The crawl space walls were just two short walls that went from house to garage.
I'll try to "attach the file" to this message, but if that does not work, I have posted the same photo on this site:
http://www.members.aol.com/mjaxn82361/crawlspace
Thanks!
Mark,
The dryer vent goes out through the wall above ground level. The floor in the entire room stays very cold, but the closer you get to the dryer, the colder it gets. I know the dryer vent is the cause of a lot of the coldness
the tile floor itself is a great contributor to the cold, the dryer vent by itself is not a huge source of cold (but some) unless maybe the wall that the vent passes thru is not insulated(?)....or has a huge hole for the vent to pass thru? i.e. the insulation was pulled out to pass the vent thru..
you mention you are not sure if there is enough insulation in the crawl space....so maybe there's not enough in the walls as well?....
.....I didn't see where you answered the question about any direct heat in the laundry room, assuming there is none, any drafts or air leaks you can seal up will help reduce the coolness, but without a direct heat source the isolated location and "cool" tile floor will work to keep that room fairly cold all the time, and it will be worse as the temp drops.
Geoff
Hi Geoff,
I was thinking last summer that perhaps the wall wasn't insulated as well, so I removed the old vent, it is a 2" X 4" wall and it was insulated with the 4" fiberglass and it was right up to the vent, and there is also 1" foam on the outside of the house. I have also caulked around the edges.
Just under the floor of the crawl space there is a heat duct that goes clear through to the far side of the laundry room, so yes, the laundry room is heated. Thats why I find it odd that the room stays so cold. The heat duct I believe is just under the floor and it is surrounded by fiberglass insulation quite well. I'm curious, is 12" insulation the norm for a crawl space floor?
Thanks! Mark
"Just under the floor of the crawl space there is a heat duct that goes clear through to the far side of the laundry room, so yes, the laundry room is heated"When the furnace is on, and there is hot air blowing out of the ducts, how much air is coming out of the duct in the laundry room???How is the laundry room connected to the house? I'm guessing there is a door. And I'm guessing it is closed most of the time. Is it an exterior door that seals tightly? Or an interior door with a gap between the door and the floor?For a room to get heat from a forced air system, there has to be a way for "cold air" to bet from the room back to the furnace.
Rich BeckmanThis signature line intentionally left blank.
Rich,
I'd have to say there is just as much air blowing out of the heat vent in the laundry room than any other room vent. I don't really have any way of measuring it but it seems the same as all the rest. When the furnace is on, the room warms up, although it doesn't warm up as much as the rest of the house, but I have always blamed that on either the tile floor, or the dryer vent.
I have posted another picture of the doorway, here is the link:
http://www.members.aol.com/mjaxn82361/csdoorway
This picture shows a view standing in the kitchen looking out into the crawl space when building the house. A doorway was never installed, we simply trimmed out the doorway is all just like you see in the photo. That's why I'd like to find a solution to the problem, the crawl space coldness really affects the entire kitchen area. I've even thought of installing a door, but to be honest with the washer & dryer out there, I'd be afraid to think how cold it would get.
Mark
Mark,
pics are great! it does help a little.....you say the heat duct runs all the way thru the crawl space...since that space has no heat source, other than the duct, you are losing a fair amount of heat to the crawl space,how much exactly, depends on how far from the furnace the crawl space is, the outside temp, how well the duct is sealed and how well it's insulated.....all of these contribute to heat loss on the way to the register in the laundry room....as Rich says FHA(forced hot air) systems need to have a return in order for the system to work properly...think of it like a FHW(forced hot water)system, the water has to be returned to the boiler to gain more heat, which is then sent back thru the pipes to the radiators (or baseboards),a loop........
as to 12" insulation being the "norm" , they would or should have put in enough to fill the depth of the joists......realize to, that since you can't access the crawl you can't tell if the insulation on the duct is really done well or not,i.e. it may have come loose over time, or was not really sufficient in the first place.....also if the insulation in the joist bays is exposed on the bottom side of the joists( most likely it is) it loses some of it's efficiency(refer to my 1st post about "air wash")......it's job is to retain the heat that is in the laundry room from "escaping" , but if there's no heat in the room, there's nothing to retain,regardless of how much insulation you have.....hope this helps a little
Geoff
Geoff,
The heat duct does run all the way through the crawl space to the opposite end. I have even wondered if possibly the heat duct perhaps was sized a bit too small but I wasn't sure. On the cold air return, the nearest cold air return vent is in the kitchen, but in a room like this, with the heat duct vent being on the very end, wouldn't the open doorway itself act as the cold air return? Sorry if this is a foolish question, I'll admit I don't know a thing about this.
I do remember them putting rigid insulation under the joists that the heat duct ran through, , I thought they nailed in 1" styrofoam, possibly 2", I didn't look that close. I didn't ask at the time, I assumed it was to help insulated around the duct a bit better. I am pretty sure that they did not do this throughout the entire room though under the joists. With the room being sealed, I don't think there would have been a way for them to put plastic under the joists though to keep any moisture off the fiberglass insulation. They used 2 X 12 for the flooring on top of the crawl space walls, and 12" of fiberglass insulation was put in. I myself put a vapor barrier in the bottom of the crawl space, and then put stone over that.
Perhaps I should take the floor up this summer, and see to it the dustwork is well insulated? If I do take the floor up, is there anything else you guys might suggest I do while under there? I also hate to do it in a laundry room, but I thought I'd install carpeting in the place of tile when I put it all back together.
Thanks a milllion all you guys for your input. I truly am glad I found this bulletin board, thanks Fine Homebuilding!!!
Mark
"On the cold air return, the nearest cold air return vent is in the kitchen, but in a room like this, with the heat duct vent being on the very end, wouldn't the open doorway itself act as the cold air return?"
I would think so.
Rich BeckmanThis signature line intentionally left blank.
Your gonna be in trouble with a completely sealed crawl space. Where are you located?
My take on crawl spaces is to treat them like mini basements. Vapor barrior on the ground rigid ins on the walls and put a heat run in there.
I really disagree with venting crawls. In the summer the temp in the crawl will be lower than the outside temp and thats how condensation forms.
Good Luck, I know I didnt exactly address your question but maybe you'll be able to prevent another problem.
MSA1,
I am located in East Dubuque, IL 61025. I'm 1/2 mile south of the Wisconsin state line, far north as you can get in IL without getting to Wisconsin.
I remember back when I was in the concrete business, there were always folks that believed strongly in venting crawl spaces, and there were those that strongly opposed it. Seems like that's still the case. In my case, I can't really vent the crawl space any more because of the way the landscaping is. If absolutely necessary, I can cut an access hole in the 8' basement walls though. Be a messy job but I'd do it if necessary and if that would help. I have read posts on this bulletin board I think where folks had an access door into a crawl space and tons of cold air was coming into the basement. If I cut the access hole though, I'm assuming I should also add a heat outlet to the ductwork as well. I could do all that, but the real hard part of all that would be to find a way to insulate the walls inside the crawl space. If memory serves me correct, they were 4 ft walls, 8" footing, and I filled it approximately 1/2 the way up with stone over plastic.
When you mentioned I'm going to be in trouble with a completely sealed crawl space, what are you referring to? Something I haven't thought of yet?
Mark
When you say the floor is tile. What kind of tile do you mean? Ceramic? Vinyl?
Why did you put that much rock in the crawl?How much room do you guess is there between the top of the rocks and the bottom of the joists?Where is the top of the rocks in relation to the grade level outside of the room?
Rich BeckmanThis signature line intentionally left blank.
Rich,
The floor of the laundry room is ceramic tile.....
I put a couple feet of rock inside the crawl space for a few reasons. The main reason though was because when I dug for the foundation, the ground was pretty wet. The "overdig" was so big that it reached half way to the garage. When I backfilled everything, I put in clean stone and compacted it, but no matter how good you compact any type of material, over the years there will be some settling. I didn't take a chance, so I put extra stone inside to allow for plenty of settling. As you can see in the first photo I posted, there was a rock retaining wall on the right side, and on the opposite side there was a wooden porch built. I didn't ever anticipate having to go back in. Also, the joists are running parallel with the crawl space walls, there was nothing holding the walls "apart" aside from the rerod I doweled into the garage and house foundations. I didn't want to take any chances on down the road after any serious settling occurred that may have pushed the foundation in, I put a couple feet of stone inside just to feel better about backfilling the outside. Once again I was trying to think ahead but may have outsmarted myself...
MSA1,
That makes complete sense. I tiled the heck out of my foundation, below and above, but as you can see in the first posted photo, the crawl space sits back to where not alot of sun can get at the right side (north side). It does stay damp outside in the back, so I can easily see in any case similar where moisture problems could occur. Might be worth tearing up the floor just to make sure that isn't happening.
Mark
Sorry Rich-forgot to answer one of your questions. Outside of the crawl space walls were pretty much backfilled right to the top and then sloped away sharply to a drain, so I would guess outside finish grade is 2'-8" higher than the inside of the crawl space.
Mark
I think you missed the question about space between the top of the rocks and the bottom of the joists. Any ideas on that?In post 17 you mentioned possibly taking up the floor. It is possible all you need is a hatch, which you could put in under the washer or dryer. But for a hatch to be useful, you need some room between the rocks and the joists. Then again, you could remove sufficient rock through the hatch (not fun, but....)What is the measurement of the duct that runs under the floor, width x height?
Rich BeckmanThis signature line intentionally left blank.
Sorry Rich. I've been away from the computer. I'd guess there is approximately 2 feet of space between joists and the rock in the crawl space. You're right, working thru just a hatch would be a real pain, I'll just take up a pc or two of plywood most likely. I'll be removing all the tile floor and putting in carpet anyway most likely to help warm the room up.
The duct itself going out into this room is 6 inches in diameter...Mark
LOL!!If there is two feet between the bottom of the joists and the top of the rocks, I would consider that to be plenty of space!!Give me a 16" by 24" hatch and I'm in business!But if you're gonna remove the tile anyway....
I asked about the duct because I was wondering if it would be possible to open the duct up before it enters the crawl and, working from inside the duct, open a vent from the duct into the crawl. But six inches doesn't allow much room to work
Rich BeckmanThis signature line intentionally left blank.
Thanks Rich...Since it sounds like I'm going to be heating the crawl space now though, I'll be taking up some flooring so I can go under there and dig enough out to insulate the walls. I just wonder if I should dig down the full 4 feet of wall to get rigid insulation on there, or if I should just insulate what concrete is exposed?
Mark
"I just wonder if I should dig down the full 4 feet of wall to get rigid insulation on there, or if I should just insulate what concrete is exposed?"I don't know the answer to that. I probably would have just done the presently exposed wall and not dug anything out. That puts the insulation 32" below grade (if your 2'8" number in an earlier post is accurate). Your frost line is probably deeper than that (40"?). So maybe another foot down.Rich BeckmanThis signature line intentionally left blank.
Thanks for the advice Rich! Be a good project for this summer...
Since it sounds like I'm going to be heating the crawl space now though
Don't forget to put in a "return" (a small floor grille), or the air you "feed" the c/s will have no place to "go."
Oh course, you want to seperate the supply (which might could just be a small 1-2" tee out of the landry room duct) from the return by as large a distance as the laundry room allows.
For your hatch, plan that a bit in advance. Otherwise you can have more fun than is allowed during the carpet install. Don't put it under the washer, though (no reason to make a leak worse). And try to not put it under the dryer, either; other wise you have to drag the dryer out of the way to use the hatch, and it will never be all the way out of the way, either.Occupational hazard of my occupation not being around (sorry Bubba)
Thanks!
I was thinking I'd open up a small access hole in the floor joists between the basement & crawl space to act as a return, and I'll put the supply on the opposite end. ....and I've got a closet in the room which is where I'll put the access door, so I think I'll be all set.
Thanks everyone for all the help and advice! Mark
To those that say to vent a crawlspace, I ask them if they vent their basement?
When they say no, ask them why not.
We worked on a house that had a small sealed crawl space. By the time we bought the house the floor had rotted so badly from trapped moisture, that the joists had given up. You could bounce on this floor. Luckily it was only a landing so the span was under 8', otherwise the floor would've just completely given up.
Had the same dryer vent problem here in Alaska. Moist air going out into the cold forms ice and the vent flap won't close properly. Put your hand in the dryer when off and it's really cold! Only fix I have found is frequent de-icing and removing lint. I would be game for a better solution.