Can a house be built without wood?
AlanB4
| Posted in Energy Efficiency and Durability on
A thought experiment, no wood beams, studs, sheathing, subfloor, rafters or anything else that is part of the house (wood furniture or other possessions are fine, we are far from a paperless society). With a price comparable or at most 50% more then a conventional house how would one build a house with a basement, main floor, second floor if possible, attic and roof?
Of course it should be insulated, the 5/10/20/40/60 would be fine, and would have the usual amenities, washer/dryer, fridge/stove, pluming, electricity etc.
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Maybe this helps you .
http://www.quadlock.com/insulated_concrete_forms/icf_floors_and_roofs_video.htm
Sure. Masonry foundations. Exterior-insulated masonry walls (or AAC or something) with stucco or brick veneer or vinyl cladding. Plastered interior. Pre-cast concrete slab floors or concrete beams with masonry infill. Metal SIP roof. Fiberglass windows and doors. Tile floors and trim. Not too hard to envision, but very expensive in an industrialized country due to the high labor costs and slower construction. Of course, it will be better in every way too.
delete
why delete?
I was going to ask why all wood-free construction would be "better in every way", but the sun came out and I decided to go out into the garden instead.
sun beats wood
its not quite rock/paper/scissors but its good nontheless
Sun beats wood
love it!
Best thread I have read since reading Dana giving umpteen answers to Jan...
The only advantages I can think for using wood to build a structure instead of modern reinforced masonry would be faster speed and lower cost of building, modifying, and demolishing it. Masonry is more durable, has better cooling performance, won't be troubled by termites, mold, fire, or children throwing metal toys at the walls (ask me how I know this... as an aside, there's a reason why CMUs are a popular material to build elementary schools out of). It won't crack finish materials due to movement and hygric cycling over time. It won't steadily deteriorate with exposure to the elements; up here in the high desert for example, the sun splits and cracks exterior wood in a few years, even if it's been sealed and protected with ostensibly UV-resistant stuff. Masonry is integrally-colored; it won't need to be repainted over and over again, especially on the exterior.
Wood is simply a low-quality material (especially modern softwoods and engineered wood products) that we use here not because it is the best, but because it is the cheapest and because our construction traditions involve it due to our vast wood resources. We don't have a huge masonry tradition like Europe has, probably because we never deforested the place to build huge wooden warships.
Nathaniel,
Good points. Masonry/concrete is the best building material out there and time and history has proven this over and over. Here in the USA timber is cheap, available and easy to work with so that is what we use. In Europe and the Middle East, masonry/concrete is mainstream. In the past decade some progress has been done with ICF taking off here in the USA.
Wood gets totally destroyed in high elevation locations. I've seen it firsthand. Like you mentioned, even with UV resistant paint, the wood splits, checks, dry rots and falls apart fairly quickly even without any rain. Painting exterior wood every 2 years is not my idea of fun.
Some of the claims made in this thread are ridiculous. Wood has been the premium environmental building material of choice in many parts of the world for many thousands of years. Japan is one example, the eastern seaboard of the United States is another. There are also places where the masonry tradition has been paramount. Usually climatic factors dominate the reasons for these time tested choices even more than material availability. It's nonsense to claim that one or the other is 'better, across the board and in all locations. Pay attention to the long history of local building traditions and you may just learn something.
It's as much economics as it is climate.
They build with stone, ceramic & mud in North Africa or Greece because structural wood is too expensive- it has to be imported.
They build with wood in cool temperate Norway (or most the US) because it's cheap, but in cool-temperate Netherlands build with brick in cool temperate Netherlands they build with brick. For them wood is an import item, whereas sand clay and straw for brick making is abundant.
https://easynorway.files.wordpress.com/2012/08/cropped-img_2957.jpg
http://traditional-building.com/clem_labine/wp-content/uploads/2013/01/Clem-44-3-Amsterdam-Canal-Houses-Traditional.jpg
^^^ even these brick Dutch buildings have massive timbers supporting wood floors inside, since there was no brick alternative that worked economically.
In Norway there has been a trend toward masonry cladding in high density communities for fire hazard reasons ( that post-dates the industrial revolution for the most part) but structural wood is still a very common building material there, as in most of northern Europe. There are stave churches more than 800 years old still standing in Norway: http://upload.wikimedia.org/wikipedia/commons/1/12/Urnes_Stave_Church_1.jpg
There are also many many massive log/stave houses and exposed post-& beam stucco-clad houses in sunny high altitude locations from the Tatras in Slovakia to the Alps from Austria to France, many of them centuries old. The notion that wood doesn't cut it as a building material at high altitudes has many existence proofs to the contrary.
Properly managed wood is a renewable, sustainable, building material with a very low lifecycle carbon footprint relative to concrete or brick (it is in fact, sequestered carbon). The stuff grows on trees. The carbon emissions from cement making are huge, a significant chunk of the total greenhouse gas emissions worldwide. Using fly-ash cement is somewhat lower carb, taking advantage of an environmental hit already taken, but any concrete construction has a significantly higher environmental hit to work off over the lifecycle of a house, than a wood house of comparable size does. That's not to say we shouldn't build with concrete, but it's important to acknowledge the up front environmental costs relative to other materials & methods.
What a climate. Two hours of sun in three weeks of drizzle. Sometimes I wonder why anyone lives here.
There's wood and there's WOOD. The wood they built those Nordic churches out of is probably 10 inch thick heartwood from thousand year-old trees. And Julius Caesar was unable to set fire to a barbarian fort made out Larch. But the studs used to build my house come from young doug firs. Termites love to eat it. A little water rots it right out. Left outside in the sun, it will twist, warp, and crack. In a fire it goes up quickly. My house is absolutely full of wood that needs to be replaced due to not-quite-perfect moisture management. Maybe if my house were timber-framed with thick wood from high-quality trees, I might see it differently. But it's not, and nothing is nowadays. The wood we build with is terrible (young softwood conifers, OSB, fiberboard, MDF, etc), and we need to go to extraordinary measures to protect it.
Most of the historical reasons why people built with certain materials was due to local availability, as Dana's examples ably illustrate. But we don't have that limitation anymore. People didn't use to have polystyrene and fiberglass insulation materials or inexpensive glass for windows, either; now we do. And if anything, this "local availability" comes down on the side of masonry since you could theoretically build structures and claddings out of unfired earth anywhere on the planet with only a small amount of cement as a stabilizer (as in fact they do wherever labor is cheap). Even cast concrete is mostly sand and rocks by weight, which can be found everywhere.
But my general argument is that masonry has a greater range where it can be safely and appropriately used, and vastly lower sensitivity to damage from nearly all sources. In general, wood deteriorates and grows mold anywhere it can get wet and stay wet for extended periods of time. Masonry doesn't. In general, wood will char, burn, produce choking toxic smoke, and act as a fuel in the presence of fire. Masonry doesn't. In general, wood can be eaten and bored through by termites and other insects. Masonry can't. In general, wood needs to be shaded and sealed from intense UV radiation. Masonry doesn't. In general, wood construction requires a large amount and variety of different materials to "finish" it that all have their own characteristics, incompatibilities, coefficients of expansion, and layering requirements that must be understood: drywall, paint, stains and sealers, chemical rot and insect deterring agents, plastic films, etc. Masonry is simpler. In an earthquake, wood can beat un-reinforced masonry, but earthquake zones don't blanket the whole world, and in those places, reinforced masonry works just fine.
It's true that the production of concrete and fired bricks leave deep environmental footprints. But repeatedly replacing, re-staining, and re-painting wood surely can't come out very well either. By way of illustration, my folks have a brick-clad house that has an addition clad with with painted wood shingles. In the 30 years they've lived there, the brick cladding has cost them zero dollars and no resources to maintain. During that time, they have re-painted the wood shingles three times and replaced a number that have rotted or blew off in high winds. Eventually they or somebody will have to replace all of them once they deteriorate completely. In addition to the environmental footprint of all of this work, it's damn expensive too. The total lifetime cost of ownership would have been much lower if the addition had been clad with brick like the rest of the house is. Another: I'm just now ripping out my bathroom shower that was framed with wood and drywall and not perfectly water-sealed, leading to termites eating many of the studs and the rest being destroyed by rot. Obviously this assembly was built incorrectly, but not only would it have been more difficult to built incorrectly out of masonry, but the consequences probably would not have been total destruction and replacement. The environmental footprint of ripping out perfectly good tile because the paper-faced drywall and studs behind them turned to oatmeal and made a tasty meal for the bugs that are perfectly capable of destroying my entire house is non-zero.
Nathaniel,
This is a false debate. You should use whatever materials your prefer and can afford.
It's not as if masonry and concrete are unknown in the U.S. In almost all locations, concrete is used where it makes the most sense -- anywhere that there is contact between a building assembly and the soil -- and brick is a very common material in much of the U.S.
Masonry walls can be tricky to insulate, and they usually cost more than wood-framed walls. But if you prefer them, spec them.
Nat, you are dealing with bad construction not wood issues.
I side with Dana and Martin as to material options.
I just attended a workshop in how to build monolithic domes. These would satisfy your thought experiment. The domes are built by inflating an air form and spraying foam on the inside. Then you hang rebar and then you spray shotcrete in several layers. The resulting structure has many advantages although it is somewhat unusual.
"The resulting structure has many advantages although it is somewhat unusual."
I'll bite. What advantages?
Monolithic domes claim to be tornado proof, hurricane proof, rot proof, termite proof, mostly fire proof, earthquake proof, cheap to heat and cool, and bullet proof. I may have forgotten a few but you get the general idea. I saw nothing at the workshop to make me doubt these claims.
Laura, Against those advantages I would put:
They can not be stacked so you are limited to one storey. For the size of the footprint at the base, you end up with much less floor area than conventional construction - and this gets worse if you try and join them. They are difficult to place and flash openings in. The geometry makes space planning difficult resulting an awkwardly shaped and inefficient rooms. Running services is much more involved and costly.
I see your point as to them satisfying the criteria of the thought experiment, but you don't really end up with many of the attributes you want in a house.
I will take Malcolm's point that these structures are round with the problems you would expect with trying to fit square people into round homes but I totally did see domes that were 2 and 3 stories high with finished upstairs.
The prosaic reality is that the reason you don't see unusual structures, whether domes, earth sheltered, movable, converted containers or any other variants being commonly adopted is that they don't make a lot of sense.
I became enamored of earth-sheltered in high school--my physics teacher built such a home. A few years ago I began looking into it seriously, and found a company that does domes and/or half-cylinders. My wife and I visited such a home and liked it quite a bit. Meanwhile, in large part due to this site I have concluded that a more conventional home that is super-insulated makes more sense...but we'll probably go earth-sheltered anyway.
Paul,
Our experiences in the world would be a lot poorer if everyone did everything the same way. What we should do as a larger culture is not governed by the same concerns as the choices we make as individuals. In a similar vein, the things I include as a builder for others are heavily influenced by being risk adverse - so I can sleep untroubled. As long as you go into it with your eyes open, why not?
Quite true. On the other hand, there's nothing unusual about no-wood structures. They're prevalent in the commercial market. Block walls, metal roof deck, polished concrete floors, metal windows and doors.
Or the other way around....timber framed mult-story and high rise buildings are being built using a variety of new techniques. CLT (cross laminated timber) floor slabs can span 20' and more.
https://www.mnn.com/green-tech/research-innovations/blogs/timber-tower-trend-reaches-new-heights-norway-tall-wood
"Masonry is expensive" is an over-simplification. If the market shifted away from wood new technologies would appear over night. Metal studs already exist. Non-flammable wall sheathing already exists. Non-flammable beams joists and rafters exist, although work does need to be done in that area. Fire insurance rates need to be considered too, in the overall big picture. Non-flammable structures would have a major environmental impact too. In the long run. Our forests and forest creatures would definitely benefit.
The forest creatures are curious as to where the raw materials for these new products c0me from.
What if we built with carbon directly sequestered from the air?
You’d have a house made of graphite then. Pretty much fireproof, but REALLY messy. It would be like living inside of pencil lead.
I may be in the minority on GBA since I work mainly in commercial buildings, but commercial buildings have been built almost entirely without wood for a long time. Most commercial buildings are built primarily with steel and concrete. Drywall is used too. There is very little wood used. It’s not like building structures without wood is a new thing, it’s just unusual to see houses built that way.
I don’t really think there is much benefit to building houses that way though. Cost is likely to be higher for the relatively small buildings. I don’t see it as “greener” either — most lumber is farmed these days. No one is clear cutting old growth forests anymore like in the old days. Steel and concrete are more energy intensive to produce too. Everything is a tradeoff.
Bill
There is a real push-pull within the High Performance Building community. On one hand they seem to advocate for the best performing components - like self-adhered WRBs over building-paper of house-wrap - but at the same time like to claim that going from code mandated assemblies to their preferred ones only raises the cost of building by a marginal amount. We can't have it both ways. If we want to go back to load-bearing masonry structures or concrete, we are either going to have to pay a lot more for a house, or lower the wages of the trades.
I grew up in a brick townhouse in Montreal that had beautiful hardwood floors, trim and finishes. it was possible to build that way at the beginning of the twentieth century because the craftsman involved lived in small tenements down by the river.
>"What if we built with carbon directly sequestered from the air?"
What if the tooth fairy actually rides a unicorn, and doesn't really fly? :-)
What REALLY doesn't fly is the energy equations for sequestering carbon from the air, and converting that carbon into a suitably structural material.
Like cellulose insulation, wood structural elements of buildings are sequestered carbon that nature sequestered directly from the air using direct solar energy.
Steel often has a minute amount of sequestered carbon in the alloy, but orders of magnitude less than what is normally released in the making of iron & steel from ore.
The carbon footprint of clay brick, CMU, and cementicious mortars are also quite high.
Sustainably harvested & managed wood is about as green as it gets in structural materials world (though bamboo is arguably even better.)
The thermal performance of structural steel is abyssmal, and needs special treatment in the design to work around it. Thermal performance of brick and stone is better, but it's still several times more thermally conductive than wood, though if the building is properly designed the thermal mass benefits can allow comparable energy use to wood buildings using somewhat less insulation.
>What if we built with carbon directly sequestered from the air?
I think you are describing wood.
I guess my jest was a bit dry, and I can't fault folks for taking words literally on a forum (what else can you do?).
I was indeed describing wood.
Though living in pencil lead sounds totally adequate to me; my partner is an artist and would love it ;)
Or as Dana puts it:
"Like cellulose insulation, wood structural elements of buildings are sequestered carbon that nature sequestered directly from the air using direct solar energy."
Proper forest management helps of course.
Steel frame construction with metal stud interior framing .....
That's what I was talking about. The standard commerical-style construction of the last century or so. It's not a new idea, just uncommon for residential sites.
Bill
> not to say we shouldn't build with concrete, but it's important to acknowledge the up front environmental costs relative to other materials & methods.
+1 on this. If you really want to use concrete, go ahead. But since we don't have a Pigouvian tax on environmental damage, voluntarily do something to offset it. For example, donate about $2000 to a cost efficient carbon reduction project.
Personally, I bought ex-pasture afforestation land that offsets more than a new concrete house every year + burning nat gas for heat + any car I want to drive + etc.