I grew up in a house with a full basement, and in some ways it was the best part of the house. Much more quiet when it was noisy outside, much warmer when it was cold outside, and much cooler when it was hot outside. And we never had a hint of moisture or cracking, even though it was a cheaply built house. This was in the desert of eastern Washington state, but only about a mile from the Columbia River.
I’m getting ready to buy or build what I hope will be the last house I ever live in, and it occurs to me that instead of having to buy a large acreage so I don’t have to worry about noisy neighbors, or move to a very expensive area like San Diego so I don’t have to worry about temperature extremes, I could just get a house with a large finished basement, and sleep down there so it’s comfortable and quiet, regardless of the conditions outside.
But in almost every place I’ve lived since high school, basements seem to be rare, and those that exist seem to be plagued with cracks and seepage.
Why should that be? If we can put a man on the moon, can’t we come up with a flexible, waterproof shell for a basement?
So, my question is, if I’m willing to pay for it, does the technology exist to guarantee me a trouble-free basement, and can I get it built correctly wherever I want it built (in the US)? If yes, what’s a ballpark figure (or range) for the price per square foot?
Thanks for any help.
ETA: Shit! If a mod could please correct the typo in “wherever”, I would appreciate it.
Yes, but the cost can be incredibly high in some cases. If you’re on wet marshy land you might only be able to do it by raising the property with fill. If you are on bedrock you could face considerable excavation costs.
For normal water problems proper drainage and sealing, and in the worst cases something like a French Drain may be needed. But ground water levels change over time, sealants degrade, the ground can move, in wet areas water infiltration is inevitable, but it doesn’t have be more than a minor nuisance with proper planning and maintenance.
I don’t know if earthquake codes are a problem in CA, I didn’t see many basements in the LA area. I certainly wouldn’t want to live in a basement in an earthquake zone. Wherever flooding happens you’ll get your basement flooded no matter what you do, which makes it pretty useless space.
Very, very few true basements here in SC, the water table is too high. I would expect that you also can’t get one in, say, New Orleans, unless you plan on building a tiny little mountain and then digging a basement into it.
Basements are common here in Bergen County, New Jersey. If the house is in a flood zone, you will have to get flood insurance and you should install a sump pump, which goes off at the first sign of water and pumps it out into the street gutters.
I would have thought that you would be better advised to build a house with a very high level of insulation. This, together with a super-efficient H-vac system should enable you to keep your home at whatever temperature you feel is comfortable at minimum cost. High levels of thermal insulation usually also offer high degrees of sound insulation.
Done right and with an array of solar panels on the roof, you would benefit from very low energy bills.
There are some places with good building conditions (i.e. easy to dig) and good water conditions where basements are almost ubiquitous, and relatively low maintenance.
Even in those environments your basement needs some features to help deal with very occasional water problems, something to keep in mind is your basement will interfere with the flow of ground water. The water will pool up against a wall, and eventually start to come right through it. The typical solution in areas where this doesn’t happen often is to have a drainage system around the basement’s “envelope”, often times tied into a city storm water drain system under the street.
In areas where water is more of a problem but digging is still easy, usually you need to go a step further than just passive draining, you’ll have a sump pump that actually sits “below” the floor of the basement. Ideally it rarely kicks on, if it’s running constantly then it’s questionable to have built the basement in the first place.
In areas with high clay soil basements are rarer, Oklahoma is famous for a lack of basements despite being in tornado alley–but unlike say, New Orleans or Florida where there’s water concerns, in OK it’s mostly a cost issue. Digging out clay is just a lot more expensive so most builders don’t do it, but if you do, you won’t have tons of water issues there.
In places with high water tables it can be functionally impossible to build a basement that can be kept reasonably dry.
We’re in northern Virginia and have a full-sized basement. We’re very lucky that our basement has remained dry through tail-ends of hurricanes and the occasional frequent heavy rains. We have a sump that we care for like a child. It runs off and on almost constantly (not so much in August when it’s dry here, but most of the rest of the year) and isn’t really that noisy. But here are the issues that the OP needs to consider if he wants to make a basement his bedroom:
Radon - You should buy radon abatement system from day one. It was never installed in the homes in our neighborhood so we had it done to our house a few years ago. So now our basement is sealed from both water and radon off-gassing (gasses are collected in a vent pipe that lets it out above our roof).
Walkout access - in some places this is mandatory by code if you turn the basement into living space. You need a fire exit and if that’s a window it has to allow an adult to quickly and easily get out, so no climbing on furniture to reach the window. Then if you have a door for access, you’ll need to pay attention again to water entry into the space. French drains just outside the door are a common solution.
Bathroom - some places also mandate a usable toilet if the basement is turned into a sleeping space. I wanted to install one in our basement (because I’m too lazy to go upstairs, our basement is just a “media” room) and learned that it’s tricky having plumbing below your septic line. You may have to buy a pump-style toilet to get the waste up into the septic lines, and if the toilet is below the septic main pipe, the waste from your other facilities may flow down into your basement toilet and overflow… eww. Get an experience plumber to take care of this for you.
I was surprised during a recent house hunting trip to the Phoenix area to discover that about 10-15% of the houses we looked at had basements. When we lived in Tucson in the 90s I don’t remember ever seeing a house with a basement (other than walk-outs perched on the side of a hill). The realtor was fascinated when I told her that where I am moving from (Southeastern PA) just about every house has a basement. Likewise when we lived in upstate NY and Wisconsin.
I always figured the thinking was that if you had to dig below a deep frost line anyway you might as well dig a little deeper and have a basement.
Because if you make something that is waterproof enough and strong enough to keep out all the water that is trying to get in, what you’ve made is a boat. That boat is going to try to float and push up hard on the house above it causing bad things.
In the Dallas area 99% of houses are slab foundations with cast-in ribs on the bottom because of the expansive clays in the soils. In a dry summer the there may be a 1-2" gap between the dirt and the foundation at ground level.
I’m guessing that if the area in CA doen’t have soil expansion or ground water issues it would be doable. A heavly reinforced poured concrete basement would probably pass earthquake codes - it’s done for large buildings.
As stated above, in southern Florida high water tables preclude basements. But hurricanes are a danger. I’ve seen proposals to build a concrete block house (a common construction material here) with no windows on the ground floor, (or only perhaps a single window and an entry door), then backfill (dirt then landscape plantings) around the entire building (or around 90%+ of it, leaving the window and doorway exposed) up to the second story windows. This would theoretically greatly reduce wind load on the building. But it would also create a complete “finished basement”, providing the insulation and isolation the OP desires. Being above grade level, there should be no water seepage issues.
You couldn’t do this on a standard residential lot, there just wouldn’t be room for your little mountain. But oversized residential lots and “pocket farms” are available, here and elsewhere. The OP should be able to achieve the desired effect almost anywhere.
One problem with a completely water-proof basement is that it would be buoyant … if the water table comes up to the surface there’s a chance your house will begin floating … like a boat. My mum’s house in the Eastern Oregon desert had a small basement, they do get the occasional tornado out there. Here in Western Oregon, basements are all but unheard of … they’d flood every winter or float down the Willamette River … both of which impact the resale value.