I’m Never Building a Basement Again
Not a question, just a comment to a community that might understand…
I’m never building a basement again. Ever.
I broke ground on our new home a few months ago. We have a walkout basement and the amount of money and effort I’ve put into building it has startled me ($65K total). I’ve blown through a large portion of my contingency on this alone. We hit a natural spring while excavating and here are the additional costs over a slab:
$6K of additional excavating and backfilling over a slab (adding time also for dealing with natural spring and gravel placement)
$3.5K of stone/gravel to place down on top of the mud we made when we hit the spring and more to fill inside the footers to proper depth
$2.0K in sand for backfill
$7K in floor trusses (first floor only)
$9.5K of ICF forms
$6K of concrete (additional over slab)
$3K of rebar (additional over slab)
$3K in waterproofing membranes and sprays and other crap that I had to deal with because I want a dry basement below a natural spring
$2K for a “dehumidifier” and ducting per my HVAC consultant – who told me basements are always humid and wet.
And weeks and weeks of time building a basement when I could have been building a first floor. I spent weeks in muck, dirt and gravel when I could have been framing.
At the end of the day, as my HVAC consultant said, they have never seen a dry basement or one that doesn’t require a dedicated dehumidifier. Really? Why did I do all this?
Take my advice and build your house above ground. Even if you’re in the Northeast where people are hobbits and want cold, damp basements with their homes. Let them dig a hole in the backyard if they want one. Otherwise, build up, not down is my advice.
Adam
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Replies
$35 / square ft of conditioned usable space isn't all that bad a deal if you ask me!
AdamT,
There are sites whee it makes sense, but as a general proposition I agree. A code compliant basement here has almost all the same costs as above ground living space, but yields dark rooms prone to water damage.
Malcom,
I'm going way above code on this basement, so I'm holding out hope that our walkout basement with large windows and 8.5' tall ceilings will yield comfortable living space. If I added this space above ground, I would know this for fact and it would have cost less.
Perhaps I'm just a bit frustrated and the end result will be what I hoped for...
Here in DC zoning limits setback, how close to the lot line you can build; coverage, which is how much of a lot the footprint of a house can cover; and floor area ratio, which is the ratio of square footage of the house to the area of the lot. The economics of building are such that virtually all new houses are built with absolute minimum setback, maximum coverage ratio and maximum floor area ratio.
However, basements are not included in those ratios. If you can figure out a way to support the soil you can go all the way to the lot line with your basement. It is becoming popular to have basements that extend far beyond the footprint of the house. Sometimes it's a good way to support a deck, which also doesn't count in the area calculations. It's also becoming popular to go deep, a builder near me just built a house with a 21' deep basement -- that extends 15' past the front of the house to the edge of the sidewalk.
Wow... I spent a little bit of time in Singapore and the church I attended did this for their main meeting space. They went underground and expanded the footprint of the building considerably.
I also hear they are doing something similar in London these days.
The 1910's Craftsman bungalow I recently moved out of had a basement that extended out underneath a cement/fieldstone porch.
Was not a particularly energy efficient detail. And was not a particularly dry basement either.
The upper story also extended partly out above the porch...
My current basement is not too shabby, but low on headroom. Needs insulation also, but is dry.
Other than storage, one big appeal of a basement (which I've always lived with) is that wiring, plumbing, and HVAC can live openly in a space that you can easily work in, making retrofit/repair work (theoretically) easier.
Is this true in NY as well? What does this look like? I’m on a slope and the basement towards the rear of the house is almost completely above ground, does this still count? I’m thinking of enclosing the area under my deck for maybe a master bedroom and enclosing the deck for a 4 season dining area above. I know not ideal and probably worth peanuts for resale but may be a cheap way to add an extra bedroom. I don’t plan on moving, anyone actually made this work and look halfway descent. It’s weird but basement at that point is practically above ground. Plumbing readily available as well.
This is really site dependent. We have a water table about 4 feet below grade, so a basement was not really an option. However, I've been in plenty of basements that had neither sump pump nor dehumidifier and were bone dry and arid, year-round. If the site was favourable, a basement offers a couple of tangible benefits. One is as a storm shelter, the other is a place to keep cool in the summer even in the face of a power outage.
Basements are great place for mechanicals, storage, and workshops (if you can't fit a pole barn or other seperate structure). It does depend on the site though -- high water tables make basements more problematic. There are many that are fine without dehumidifiers though, and I'd say most probably don't have leaks, but they have to be built correctly and that's not always guarnateed.
You're case with the spring is pretty unusual. I would be concerned with high water table at your site, so it may be worth doing some core samples to be safe. High water tables can cause problems for ALL foundations, and that can mean shifting/settling down the road and all kinds of expensive problems. My recommendation to you would be to have a geotechnical engineer check things out at your site to see if you need any special anchoring to stabilize anything. Some extra caution now might save you a LOT of money and headache later.
Bill
I have to admit that whenever I hear "high water table" my first thought is "fix your damn gutters." So many people get told that they have a high water table when the reality is that rainwater is running down into their basement. Yes, if the excavator is digging along and water starts flowing out, that's a legit high water table (or he just crushed a water main). But if you get water in your basement after it rains that's rainwater.
I'm going to be Contrarian and make the case for basements. I was raised in New England, where people take great pride in their frugality, yet you almost never see a house without a basement. First, your foundation needs to go below the frost line, which is 40" in southern New England and deeper further north. You're going to want to put the first floor at least 3' above grade so that when there's three feet of snow on the ground in the winter you can get out your door. So you're basically going to be building 8' concrete walls for the foundation either way. The question is whether to dig out the soil between the walls or leave it as a crawl space. To dig it out, the excavator guy is there already, you've already paid him for the day and he can finish it the same day. If it's dug out every other part of the home construction is easier. If you leave it as a crawl space you have to encapsulate it anyway to keep your plumbing from freezing, which probably costs about the same as insulating the whole basement.
Even if you leave it unfinished you can use it to house your mechanicals, which otherwise would take up space somewhere in the finished part of the house. So you're basically getting finished space for the cost of unfinished space.
DC,
Half-below grade basements and walk-out ones should have another name as they don't share many of the attributes of the fully submerged ones.
The DC zoning code distinguishes between "cellars" which are less than half below grade and "basements" which are more than half below grade. All those good things I said about basements in #2? They don't apply to cellars, which are counted as part of the finished area of the house whether they are finished or not. There's been a lot of back and forth in the past couple of years about how exactly they're measured -- can you pile up dirt around the foundation to turn a cellar into a basement? I haven't kept up but as land gets more valuable it gets more contentious.
I have to admit, if a basement needs to be fully below grade, I've been in one or even seen one in my life.
Basements make a whole lot of sense where the water table and flood plane allow for it (and those things are often related).
Reasons why:
- You're building in a part of the site that already needs some amount of excavation anyway. Sure, it's deeper, and you need a bigger foundation, but it's not increasing the footprint of the house.
- Soil temperatures moderate the heating/cooling load of the additional space. It's likely a basement has the best thermal characteristics vs. any other floor of the house.
- Zoning ordinances restrict impervious coverage and building coverage. Basements allow for more useable space in the same coverage area.
- As mentioned in other posts, they're great places for mechanicals and utilities, even if you never use the basement for finished space.
- It provides a place to service first floor plumbing and electrical changes in a a much easier fashion than a crawlspace, let alone a slab.
But to channel the theme of your post, I'll say: "I'd never build a new crawlspace."
It's one thing to make an existing crawlspace useable, but if given the option in new construction, I'd switch to a basement or a slab if a basement was impractical.
I built a crawlspace (sealed and "conditioned") and wish I had a basement. I'd gladly pay the premium...as I have all the issues noted above regarding zoning, lot coverage, etc. Over the long term I'm sure the OP will come to appreciate the basement.
VERY happy to have at least a crawl instead of a slab, also for all the reasons noted above...
Adam-we will stipulate your costs are representative. However, it really is site dependent. On small constrained lots ie less than a 1/2 certainly, with height zoning restrictions, you must build down to get teh square footage uo need these days to justify land prices in places like nyc, hosyin, Washington DC, all of California, etc. we actually found it was highly cost effective to max out basement space, suspending front porch and garage to create additional basement space below. That said the one thing we can all agree on is -no crawl spaces ! What a nightmare with limited utility-at. A minimum you need a rat cellar concrete floor or just forget it. Build on piers.
deucevantage,
Our climate is ideal for crawlspaces. The typical excavation is about 30" deep leaving you with a 3' crawlspace. To me they make a lot of sense. A house wth a trussed roof and crawlspace is by far the easiest to renovate or add services to. It is much less likely to flood, but unlike a basement which inevitably either gets some finished spaces or used for storage, the consequences aren't serious. They work particularly well on sloped sites where one side ends up high enough for a water heater, while still keeping the excavation to a minimum.
On a typical construction site, who are the highest paid guys? The plumber, the electrician and the HVAC guy. With a full basement it's a lot easier for them to do their jobs, which means they take less time, which means they charge you less. Insulating and air sealing is much easier too; you use somewhat more material but you can work standing up instead of on all fours which means it's easier to do a good job.
In our house plan, we are debating a basement vs slab. Or a partial basement/slab combo. Not sure a partial basement makes a ton of sense or not either, the extra detailing might add complication. But one of our driving ideas here is that being in the midwest I would like somewhere to go in case of a tornado. A basement is NOT a true storm shelter, but it's a decent bit better than nothing I think. Of course you can build a proper storm shelter on grade too, but that's another cost.
Is that $65k including the labor to do all that work?
I like basements in general. They're an efficient use of building footprint.
However, as others have mentioned, its site specific. If I have acres of land and no zoning committee to deal with, your comment makes sense. If you have limited space in your lot, well, it can be pretty important for quality use of space, density, and/or quality of life.
BTW, my basement isn't damp. I designed against it.
Also, you get into daylighting design, and it can be pretty good space.
As DC mentioned, many zoning considers 51% sub grade to be a basement. where 49% of the wall can be above grade and can have rather large windows. Moreover, sub grade terraces/light wells can play a really good design role.
One thing you dind't include for arguments sake is the hypothetical cost of doing a slab on grade. The delta between the a basement and slab on grade can be not that bad considering what you're getting.
Another thing you didn't include is the cost of another storey in lieu of a basement.
I am planning a garden suite build, and as much as I want a basement, I'll most likely do slab on grade, to lessen the project cost. It irks me inside, because a basement isn't something I can add on later.
But ya, I get what you're saying: concrete wall construction costs more than wood construction. Is it that much more to freak out over? I think it depends on your site conditions and overall project.
With some saying a basement is mandatory in northern climates I'd recommend looking into frost protected slabs that have insulation fanning out on the perimeter, though for areas with height limits a walkout basement seems like it could be very nice if waterproofing is done well and it's not on top of a natural spring. Ideally that would be discovered in time to move the house site away from it, but it sounds like enough has already been spent to deal with it. In my area of NC I see whole house/crawl space dehumidifiers as a good idea in general, and $65k for a basement doesn't sound that bad given how expensive housing in general is at this point.
I’m a builder. I did the same thing for a client. I gave them a price to do above grade but they wanted a walk out. Once you start in there is no turning back. 6’ of ledge had to come out. Major springs revealed do to all the rain this summer. 120 k over budget on this alone. I could have framed there house and has an on grade slab and frost walls for that same cost. I think people have it in there heads that it’s cheaper to build down. It’s cheaper to build one story and go big then to build up or down.
Best