Your thoughts on my basement plans

[EddieWalker]

I've had two road bores done under the highway to get water and natural gas to my land. Price is based on the size of the hole bored times how far you want to go. Both where 100 foot bores. The big one was $7,000 and the smaller one was $3,000. My guess is that I would be in the $5,000 for every hundred foot range, which really isn't an option.

There will be no water lines anywhere near the basement, so broken pipes are not a concern. There was a lady down south who drowned in her basement from water filling it up and she couldn't get out. This is always a fear, but mostly from the house collapsing over the opening and not being able to move the debris to get out. I've read that having a bottle jack inside the room is good for this. Not sure if I'm crossing over into the crazy world or not in this, just home sick and doing some thinking and hopefully learning.

 

[EddieWalker]

I've had two road bores done under the highway to get water and natural gas to my land. Price is based on the size of the hole bored times how far you want to go. Both where 100 foot bores. The big one was $7,000 and the smaller one was $3,000. My guess is that I would be in the $5,000 for every hundred foot range, which really isn't an option.

There will be no water lines anywhere near the basement, so broken pipes are not a concern. There was a lady down south who drowned in her basement from water filling it up and she couldn't get out. This is always a fear, but mostly from the house collapsing over the opening and not being able to move the debris to get out. I've read that having a bottle jack inside the room is good for this. Not sure if I'm crossing over into the crazy world or not in this, just home sick and doing some thinking and hopefully learning.

 

[forgeblast]

Just wondering if a picture would help us out to see the "lay of the land". Wasnt there a post where someone made a root cellar and put a shed on top. Easy access will allow you to use it. There are products like drylock that will help seal the inside of the concrete walls. We used it on our basement (walk out) after fixing the gutters and it made a huge improvement.

 

[MossRoad]

I've had two road bores done under the highway to get water and natural gas to my land. Price is based on the size of the hole bored times how far you want to go. Both where 100 foot bores. The big one was $7,000 and the smaller one was $3,000. My guess is that I would be in the $5,000 for every hundred foot range, which really isn't an option.

There will be no water lines anywhere near the basement, so broken pipes are not a concern. There was a lady down south who drowned in her basement from water filling it up and she couldn't get out. This is always a fear, but mostly from the house collapsing over the opening and not being able to move the debris to get out. I've read that having a bottle jack inside the room is good for this. Not sure if I'm crossing over into the crazy world or not in this, just home sick and doing some thinking and hopefully learning.

OUCH! That's pricey. Our neighbor has cable TV and internet on and overhead line. It started acting up and the cable company came out with a directional boring machine and did two bores. One under the street to his house, they pulled the cable back to there. Then another bore down the block to the cable box. I was completely surprised that they'd go that route VS just replacing the overhead lines. One person had to locate the buried utilities. Two guys to do the boring (only took them about 1/2 an hour). And a fourth guy to hook it all up. VS one guy on a ladder, a box of wire and be done with it. Anyhow, I realize a cable pull isn't a 4" drain line.

What are you going to do for a door overhead? My father built a bomb shelter into our house when he built it in the late 50s. You know, to save us from nuclear attack! :laughing: Anyhow, it had a reinforced concrete ceiling, but the trap door was 4 x 8 double thickness plywood on a counterweight. I asked him how would that protect from a bomb. He laughed and said it wouldn't. He hadn't finished it. He was going to install a concrete door with hydraulic system to open it from underneath and never got around to it. A couple very large hydraulic rams and a hand pump. He said it would have to be big enough to lift the door and anything that may be laying on top of it, like several oak trees or a truck. As it was with just the wood, there were various tools down there that you could remove wood with. As I recall, it was about 16 X 16 and 8' deep. A couple cubbies about 4' deep on each side of the fireplace foundation. We'd hide in the cubbies during storms in case the trap door caved in. Thankfully that never happened.

 

[MossRoad]

Oh, and you haven't even come close to crossing over into crazy yet... :laughing:

 

[westcliffe01]

Eddie, rest assured the water will find a way to get through your defences. It has forever and will do so at the molecular level. I thought it was the builders maxim, that "water always wins" ?

Just do it the old fashioned way that the rest of us do and instead of trying to seal it off, put the pond liner down first, then a layer of gravel on top to provide a flow channel which leads to your sump pump. A lot of homes put the sump pump in a pit outside the foundation with a cover on top, because the inside space may be all finished. So long as the sump pit is deeper than any part of the concrete by 1 foot or so, and the water is able to flow freely to the sump pit, you will be all set. Don't forget that you want gravel against the walls, since water coming through the wall is no better than the floor.... Then pour the floor, do the walls and build like you plan to. A backup pump is always a good idea and a float tied to an alarm to warn you that water is rising is also helpful.

If you want to keep the floor warm, put rigid foam type 250 extruded polystyrene on top of the gravel before you pour concrete. Nothing will suck heat out a concrete floor faster than contact with 50F ground water... If you do that, then consider installing PEX for radiant heat. It will also dry out the concrete over time. Absorbent floor treatments like carpet are of course the worst possible thing in any situation where moisture could ever be a problem. If you go radiant then you can tile and do area rugs. The floor will not be uncomfortable underfoot anyhow (in winter with radiant heat) and in summer it may be refreshingly cool.

 

[dragoneggs]

Eddie, rest assured the water will find a way to get through your defences. It has forever and will do so at the molecular level. I thought it was the builders maxim, that "water always wins" ?

Just do it the old fashioned way that the rest of us do and instead of trying to seal it off, put the pond liner down first, then a layer of gravel on top to provide a flow channel which leads to your sump pump. A lot of homes put the sump pump in a pit outside the foundation with a cover on top, because the inside space may be all finished. So long as the sump pit is deeper than any part of the concrete by 1 foot or so, and the water is able to flow freely to the sump pit, you will be all set. Don't forget that you want gravel against the walls, since water coming through the wall is no better than the floor.... Then pour the floor, do the walls and build like you plan to. A backup pump is always a good idea and a float tied to an alarm to warn you that water is rising is also helpful.

If you want to keep the floor warm, put rigid foam type 250 extruded polystyrene on top of the gravel before you pour concrete. Nothing will suck heat out a concrete floor faster than contact with 50F ground water... If you do that, then consider installing PEX for radiant heat. It will also dry out the concrete over time. Absorbent floor treatments like carpet are of course the worst possible thing in any situation where moisture could ever be a problem. If you go radiant then you can tile and do area rugs. The floor will not be uncomfortable underfoot anyhow (in winter with radiant heat) and in summer it may be refreshingly cool.

Good stuff west, you are making me want to put radiant heat in my basement floor and finish it with a man cave style.

 

[Bengineer]

Eddie, with the difficulty in getting natural drainage you describe, I think if it were me, I'd build an above ground storm shelter. It just seems to me that it would be easier to build and to keep dry, especially if there are torrential rains associated with the storms. Additionally, I think it would be easier to ventilate, put an alternate escape hatch in, get out of and so on.

Another way of looking at it is there is lots of info on above ground shelters and none on waterproof (as you describe, without drainage) underground building.

 

[dragoneggs]

Eddie, what else do you plan to use the space for other than storm shelter? Since you say you want to build an attachment to your house I assume this will be accessible from the inside? I suggest you make it a comfortable functional space you can use year around. One very nice thing I like about below ground basements is their ability to help regulate the inside temperature of the whole structure. The below grade room in addition to the added thermal mass helps both summer and winter. It can function as a nice natural air conditioner in the summer with adequate air movement.

 

[EddieWalker]

A little more info. Our main goal is to add on a large 24x48 room that has 12 ft walls and exposed beam ceiling with a 6:12 pitch roof. If all goes well, I hope to start on the dirt work in the spring. Just need to finish a few projects over the winter first and save up enough money to get started. This is my number one priority project, and something I've been day dreaming about for years!!! Off to the side there will be a 16x16 sun/garden room for my wife. This is what she has been dreaming of having for years.

The dimensions for everything is pretty much set in stone. After the two tornadoes that came so close to us last winter, we go to thinking that it would be nice to have a tornado shelter. First, and most obvious plan was to build it above ground into the corner of where I plan to build a new workshop. Simple, easy and effective. But not really ideal. One of those projects that I'm working on now is a canning/processing room on the other side of our house from where the new room will be built. Karen is really into gardening, and we are both borderline preppers with a desire to be as off the grid as we possibly can. Storing food and supplies is always going to be something we will never have enough space for. The canning room is 12x24 with quite a bit of storage space, but we can see where it's not going to be enough fairly quickly.

Out thinking then turned to adding a small basement. In all reality, I could make it a lot smaller, but with the size of the room above being 16x16, I feel it just makes more sense to use the walls of the basement as footings for the sun room above it. Access will be from an exterior door inside the sun room that leads to stairs down to the basement where I will install another door. I'm still unsure about this lower door. I doubt a standard exterior door will be enough is we are hit by a tornado. I can get solid core doors used in commercial buildings that would be a lot stronger, then add extra hinges with longer screws to hold it in place, and add a massive bolt system to lock it into place. This is all in the air as I tend to let the smaller details wait until I have something to work with and then make a final decision then. Under the stairs will be a camper type portapotty with plastic bags. I plan on having some cots down there, or a couple of futons and lots of shelving for canned foods. I don't see any need for heating or cooling it year round since we will rarely go down there except to increase our food supply. To keep warm, I'm sure we will just stock it with blankets or maybe an electric space heater if we have power, if not, we are in survival mode and just going to listen to the battery radio and huddle up in blankets.