I’ve been working on a project in a house that I almost bought. The work involved removing the entire floor from two rooms in a house, and half a third room, and replacing it. It was largely due to lack of ventilation. I’m curious what solutions others have used for similar problems since there is a possibility that I may still buy this house.
A Few Details – The relevant part of the house appears to be a 1940’s ranch. It could be earlier. (Floor beams were on 24″ centers and were full 2×8’s, about 13’6″. I know they were overstressed.) There was a center girder of doubled 2×6. It gave way too.
The wood was covered in many areas with white mold (?). It was dry to the touch. In many areas portions of the beams were rotted off and missing. In both rooms where the floor was replaced, the beams virtually broke as we took them out, except for those that had cracked before we opened the floor. There was no insulation at the floor level.
The distance from the bottom of the beams to the top of the earth floor below varies from 6″ to 24″. The floor is heavy clay soil. I’ve put black plastic down to help keep some moisture out.
Blockwork ventilation is not the answer. In the back of the house, the level of the soil is basically at or above the bottom of the siding. There is not a true foundation. House was built on piers spaced about 8-12′ apart, then filled in with whatever was handy, or not. The level of this soil outside allows (I think) some water into the crawl space. Regrading isn’t the answer since the house sits in a low part of the lot, kind of in the middle of a hill. (I know something needs to be done to get the dirt off the house. That’s not my main concern here.)
Maybe? I’ve thought about putting some kind of ductwork, maybe 6″ or 8″ pipe, into the basement that I can direct out thru the walls 2-3′ high, possibly with a motor that would be hooked to the light switch in the rooms, guaranteeing that it would operate for a few hours a day. That’s about as definite as I could get. I even thought about going all the way out through the roof. But that seems wasteful.
Building inspector suggested that I use window wells and passively ventilate below grade. I don’t like that because it presents the problem of water getting into – and out of – the wells. He didn’t like the motorized ventilation because someday the motor might burn out.
Has anybody run into this, and how have you handled it?
Replies
"Regrading isn't the answer since the house sits in a low part of the lot."
Rule # 1. You have to keep the water out of the crawlspace first.
"That's not my main concern here"
2. See rule # 1
Im not sure how you can do it but grading to a drain or pump or whatever is your main concern.
Once it is under your house it is much harder to fix.
Will Rogers
Thanks for taking time to respond.
Water isn't running under the house. I know having soil wet or dry against the outside of the house is a problem. But having the soil against the house isn't the main problem.
We had some pretty substantial rains recently and when I went to the property there was no standing water in the basement, not enough to pump or drain. The only evidence of a water issue was a little damp soil in one of the rooms - the bedroom on the northwest corner. That is the room where the clearance to the ground was the least when we started. We did excavate some and there is more air circulation now than before - 15" or so from the plastic to the bottom of the beams.
The other big problem area for the wood beams was the living room - the southeast portion. There was no water intrusion there, and never has been from what I could see. So regrading will have no effect. But the living room can't be ventilated directly since there's a large concrete slab across the front of the house in that area.
FWIW, the other bedroom, which is south of the first bedroom and west of the living room (an ell shape) required no beams to be changed whatsoever. I had to take part of the floor out there to work on the concrete below the wall, but other than that, no problem.
Don K.
EJG Homes Renovations - New Construction - Rentals
Bump
I'm not sure what the the solution is going to be for this house.
Are you saying that it needs to be vented?
They do have motors for venting radon gas.
If they are designed to run for years venting radon I think they would work for what you want.
Ask the inspector if he would pass that."There are three kinds of men: The one that learns by reading, the few who learn by observation and the rest of them have to pee on the electric fence for themselves."Will Rogers
Popawheelie-
It's coincidental that you brought up the radon gas systems. I hadn't thought of those systems per-se until yesterday when the FHB magazine got here and there was an article that talked about house ventilation, which mentioned the same thing.
I am going to look into that. House definitely needs venting in parts of the crawl space. Hope the fans aren't too expensive.
Don K.
EJG Homes Renovations - New Construction - Rentals
Hi Don:
What about jacking the place a foot or so? Easier said than done, but it sounds like the primary problem here is elevation. Post on pier makes it real easy to find your lift points. Of course, it would have been a lot easier before the floors were replaced.
If you get it up, you have a chance at making passive ventilation work along with the opportunity to regrade the exterior a bit.
-t
I've thought about jacking it. I'm really leery, partly because there was other work done to it before I got there. I don't know how or if it would hold up. The original house where we worked is about 28' x 30, but there's another section to the west about 28 x15. There are also porches front and back, poured concrete floors, 2x4 cielings - just a mess waiting to happen. Seems like too much to go thru under the circumstances.
Don K.
EJG Homes Renovations - New Construction - Rentals