1,000 Year Doghouse

Ferrocement is incredibly strong yet inexpensive and easy to build with. In this doghouse, I know my dog will be safe from hurricanes, tornadoes, earthquakes, and small tonnage nuclear detonations.

Step 1:

Assemble a dense wire mesh in the shape desired. The surface must curve in two planes, as on a sphere or an egg. Flat plane, cylinder, or cone surfaces will not be strong. Use at least 4 layers of hardware cloth and/or chicken wire. The finished wire mesh should be mashed or laced to less than 3/4 inch thick with no holes large enough to stick your little finger through.

Comments

[iti]

ferrocement is not waterproof. You can add waterproof agents to the mix before applying, or you can use housepaint, or roofing paints or sealers to seal it. But as it stands? This little guy will be really wet if it rains. :) Nice job building the wire frame, and mudding it. Looks great.

[vermeuliscious]

I seriously doubt the water will pour through an inch of concrete. If the house were submerged it would wick through, but I'm sure mr frisky will be just fine in the rain.

[iti]

lol. Actually, rain will pour through 3 inches of concrete.  Lookat any road, driveway, carport etc.  Concrete is porous. You mightlike to do a google search on ferrocement, there are several excellent sites.

It needs a sealer of some form.  Because the house is curved, therain will run off, but if it rained for a week, it will  obsorb thewater, and sooner or later the saturation point will be reached andwater will run through.

It has tiny fractures throughout, over time if not checked, they grow,turning into hairline cracks, then big cracks.  Any wire insidewill rust, and expand the cracks more.  etc etc.

Sealants are required.  Just do a test, try it yourself.

Even cement walls on a house must be sealed on the outside if you wantan fha loan. Why?  because they will do the same thing, absorb therain, water from sprinklers and then transfer it to the inside.

And in the case of a sprinkler? It doesnt take days, lol. I tried this one too.  It was fun to watch and see that thepattern on the inside was the same as the outside.  I nice curve.  

[clevernonsense]

I made a rain barrel from ferrocement; no sealant, no leaks.

[milesnorth]

Love it! need to make a insulated dog house and this is giving me ideas. We live in Alaska and I think this might just be part of the trick. Cool.

[rawknexstuff]

I want to make a fort out of this!!!!! Then again, with the 3-4 feet of snow and ice that I'm buried in, I could make something similar.

[anatole]

You did a nice job. A lot of work for a Dog House but also an interesting and rewarding experience I'll bet. I understand boat hulls were made similarly years ago and lasted a hundred years. In fact I read somewhere that one is still in existence floating somewhere. Ferrocement is labor intensive and some have built actual homes with this methodology. I wish I was a young man I might build a home in concrete as I think it is a very green and long lasting. Thanks for the project info, very nice! Anatole

[xd12c]

http://www.monolithic.com/
I would like to get/build one, but I don't have the resources :?

[cd41]

i want to build a home of it now and with alot of green stuff.. maybe someday.. i would post a video or instructable of it of course!

[ClayOgre]

Actually, as I understand it, the manufacture of cement isn't all that green. However, the stuff sure is cheap. I have considered using this idea to build an old fashioned claw foot bathtub, then just coat the inside of it with that acrylic stuff they make for refinishing bathtubs. I have also heard of people making hot tubs out of ferro cement.

[spark master]

In the sacred other Eath News of olde days, they did articels where people built Chord wood or bottle/can cement structures. Like this lay down a foundation /footing bring to grade or above. Then layer by layer use old bottles/ beer cans (all washed and dried)pointing the open ends into the structure (water can not fill them, should you get a leak), if you use chord wood use sold whole logs cut into say 2 foot lenghts. For a big structure youbuild a moving armature that rotates and raises, so you can keep the  dome shape (think lemon wedge, where the peel faces the wall and pivots on the thin edge)If you lay it out right , you leave space for doors windows etc. 

Cement structures take time to really dry out and some peolple compain of humidity for several years. I would think in SW USA this could be a lucky good thing, in Manitoba maybe not. 

Jest fer fun you could, with a small dome  use bottles (blue green or flint) with the ends exposed to the light so internally you have illumination.  A design even, say a constellation if it is a shed type building.  In a small structure like for the dogs you could make a two layer bottle wall (no tilt, then put your ferro cement screening and maybe 2-3 in a cluster at the top as a skylight.  If you use small bottles like mini juice things or ginseng bottles, you could do constellations and being a dog house do , errr do SIRUS, (Cannis Major).

The final coating can vary but the stuff they use to lay ceramic tiles is water proof on drying . Big bro waterproofed an entire basement with it, filled cracks and space too, so it is like hydrocement in that it filled cracks and stayed waterproof (over 10 years, no leaks). When we did the facade onhis bar/club we used it there as well.

It pays to add something to the cement mix that makes it water proof over a final coating of paint which peels.  It would be great to paint over it anyway.

A structure as small as this dogigloo might be better made with Struclite and then a finish coat of water proof cement with lotsa bonding agent. Structite is a cement mixture with styfoam and pearlite (perhaps) mixed in. With your wire mesh it should be self supporting and will be cooler in summer warmer in winter.

seeya in the funny papers

[jamiebeau]

How about using a hypertufa material composed of cement, perlite and peatmoss to make it light enough to move about? Actual concrete would be a very heavy base to move about.

[dome_head]

Would not be as strong, since ferro cement gets its strength from the compressive strength of the cement.  Make it thicker to compensate, but this increases weight.  Each type of structure would have an optimum set of compromises between weight, strength, cost, etc.  The additives would improve insulating value.

 

[MacGyver1138]

This is a pretty cool idea. Are there any paints that can be used on this?

[jsummerlin]

Having roofed for more years than I care to share. An excellent product and compatible with most substrates is Elastomeric. Can be purchased at your local home center. Latex product cleans with water. When applying several layers use the fiberglass re enforcement mesh 6" wide roll.

[vhcl]

You can use regular water base paint or better yet the anti fungi type like the one regularly use in bathrooms, or even better get it paint while the cement is drying using diluted paint and when it dries it will be fix forever, Imagine a dog house with murals on the walls. How cool is that!!!

[thepelton]

Painting on fresh plaster is the concept for fresco. What occurred to me is that you could cover the outside with glass beads, stones or something of the like for a kind of mosaic decoration.

[studiobil]

Just a note about rust and concrete. They don't mix! Avoid using rusty metal ie rebar, chicken wire, wire ties etc. The moisture in the cement mix will help accelerate rust in the end job which will eventually cause cement/concrete "spalling" - more dramtically known as 'Concrete Cancer". Yikes! This causes the concrete to crack from the inside and eventually it fails. If you see any rust on reinforcement for construction projects etc it means the inspector isn't being tough enuff -- rust is a no-no. However unless you're building a house, hi-rise or boat, rust is probably not an issue. It can take 10-30 yrs to destroy your project! I don't think Frisky is in any immediate danger!

[Trollfish]

(removed by author or community request)

[MrLWJ]

Just to clarify. Liberty ships were not built by the navy nor were they made of concrete. They were built by a number of contractors, Kaiser, Todd Shipbuiling, etc. They were built of welded steel plate, a new technology at the time as ships were built with rivets till then. The only Concrete on the ships was used as a checp version of armor around the bridge and gun tubs.

[glorybe]

It is ferro-cement not ferro-concrete. The wire replaces the stone aggregate in concrete. Also to space the layers of wire some people make little slugs of cement to use as spacers between the layers. Ferro-cement can be super strong to say the very least. It is a wonderful medium and the world is just catching on to it. Homes can be built with this method.

[Briguy9]

I thought it only works when the dog is inside the house? lol.

[glorybe]

There is a huge error in this how to. Concrete is not cement. Trying to stuff concrete into this mesh will not go well at all. Ferrocement is usually about 15% cement, 85% sand and no rock at all. Water is added until the mix is a sort of stiff , plaster like, substance. Also, good ferrocement jobs require either a form or someone on the inside keeping the mix looking decent so that the mix stays within the wire matrix.

[extrordinary1]

I've seen monolithic domes made with air forms inside the metal frame and allow the exterior to set up first, then go inside and finish after deflating the airform. I hope to someday build a home, but not dome style, but still stylish.

[bassmasta1010]

it would be awesome if you had a hill in your back yard and you put the house into the hill (except for the entrance/exit hole)..............BUNKER STYLE!!!!

[watermelon]

Ever thought about using that stuff to build him a boat?

[smokehill]

Ferrocement is used for boats, often in primitive countries. When I first looked into ferrocement for building houses, about 30+ yrs ago, in the old Mother Earth Catalog, they showed pictures of some native fishermen on the beach, making big "forms" out of hard-packed sand -- basically shaped like an upside-down boat hull. Then they'd lay chickenwire over it, tightly woven, and start packing in the ferrocement with trowels. When it was cured, they'd flip it over and have a boat. In the old original Mother Earth catalog they showed people who'd made their houses of ferrocement, and often many of the interior walls and furniture (or at least chair and couch-like platforms to hold cushions. For big projects you need to use re-bar to hold the chickenwire skeleton stiff. Some say you should really use thicker, stronger mesh than chickenwire for larger structures, but it probably doesn't make much difference as long as the cement coating is thick enough, or unless you're aiming for a 40-yr lifespan for the bldg and it takes a significant load. CAUTION: When you pick the chickenwire or welded fencing wire for the skeleton, make sure you do NOT use the newer plastic-coated stuff. While it might seem like it would hold up better, I'm pretty sure the cement will not bond to it properly. Using dirty or rusty chickenwire is also a no-no. Some cement guy who does a lot of re-bar work could probably also give us some useful hints on tying the wire, etc. I believe chickenwire is sometimes available in different gauges, like chain link. Obviously you should use the heavy stuff if your structure is bigger than a doghouse.

[Full Frontal Graphic]

What is the problem with using rusty wire? I'm building some steps, taking a long time, and the re-bar is rusty... ... is this going to cause issues?

[Goedjn]

A little bit of rust is actually helpful, because it makes a pitted surface. Too much rust forms a dusty/flaky layer that helps the metal slide within the concrete, and is therefore bad. If you're doubtful, take a stiff brush to the armature, and knock off anything loose. --Goedjn

[thepelton]

Rust is corrosion. Rust will continue inside the concrete until your chickenwire base is powder. Ever see an old ship with orange streaks on it? That is Rust, and it is causing the ship to degrade to powder.

[smokehill]

I was hoping someone really experienced in cement would answer this -- I don't really feel qualified. Since chickenwire and smaller-gauge stuff is so thin, I believe rust is more of an issue, since there isn't much metal to begin with. For regular rebar, I don't think minor surface rust is a real problem. I've seen somewhat rusty rebar laying in the trenches for footers, before the concrete truck arrived, and no one seemed concerned, including the inspector that approved it. Once the rebar is dropped onsite, it's often many days before it actually gets installed and covered with concrete (sometimes even weeks), so apparently the surface rust isn't an issue there. I do recall reading, decades ago, that rusty chickenwire should be avoided in ferrocement, but I'm just guessing that the thin gauge of the wire is the issue here.

[Full Frontal Graphic]

Thanks smokehill, I appreciate the answer. I think you are substantially correct, and I've been assuming pretty much what you said. I've since learned that the reason for steel or iron in cement is that cement is very resistant to compression, while it only weakly resists flexion, tension and torsion. The metal re-(inforcing) bar and chicken wire help to resist tensile forces, while torque and flex are resisted by the combined structure of the tied/wired framework of metal. The combination of the cement mass and the armature (the tied wire/rebar structure) gives even more strength than either material by itself. So depending on the stresses which will affect the finished project, the armature becomes more -- or less -- crucial. On the steps I'm building, rusty rebar should do just fine, the main load is going to be people walking on it (compressive forces) and we don't live in an area where frost or freezing will likely have a significant impact. Thanks again for trying to help, smokehill. Much appreciated.

[watermelon]

I have first hand experience helping to build a 73 foot motor-sailer. 1/2" hardware cloth made of pre-galvanized steel wire was used - meaning that the wires were not welded where they crossed to eliminate the need to cut out pieces for fitting curves. We laid up 11 layers. The advantage of a boat over a house is that a boat can take you places and can provide a living. We planned dive charters in the Caribbean. Ferrocement houses can be free-formed with just chicken wire if enough layers are used. The Japanese build ferrocement boats all of the time using wood forms and chicken wire. Damage from things like hitting a reef are very localized and will seep from damage that would knock a hole in a wooden boat. Most ferrocement housing projects, however, are done to provide the interior layer for a geodesic shell that can be covered with a thick layer of polyurethane foam. Some builders even do the exterior polyurethane shell first and then come inside to tack the wire followed by application of the cement.

[smokehill]

Wow -- Ferrocement has fascinated me since I read those old Mother Earth catalog articles. When I was stationed in Turkey in '72, I saw several rural motels and small housing projects that seemed to be basically ferrocement domes, but my Turkish wasn't good enough to get a clear explanation of how they did it. I've always wanted to do a ferrocement project, but never seem to do it. I had a plan for enclosing our 50-dog kennel with a ferrocement dome, but wound up cutting back to 25 rescue dogs and gradually moving them into the house & an attached bldg to make the upkeep easier, and free up a bunch of chainlink panels to make dog runs next to the house. We still need a few doghouses in the adjacent yards, so I may try this idea on a small scale. Any thoughts for basic insulation that a dog can't chew? I thought about using that expanding spray foam, but I suspect the dogs would regard it as entertainment instead. I suppose I could make a dome, cover it with the spray foam, and then do another ferrocement dome over that ... but it seems like a lot of work, and a REALLY heavy doghouse to move around occasionally.

[KEYBOARDISBROKEN]

put it on rollers

[Lithium Rain]

I wonder if a similar idea would work to make a storm shelter? Dig a hole, line with mesh in this manner, then line with concrete and build a roof in the same way. Hmm...

[solitary man]

Here are a few positive and informative articles about the "green" dynamics of concrete building by the Portland Cement Association

http://cementamericas.com/mag/pca-honor-green-efforts/

When I say "green" I also mean resource efficient. :)

http://cementamericas.com/mag/cement_cement_concrete_environment/index.html

Have a good one. :)

[LAWNPRO]

very slick idea no more dog chewing up the house

[fishcatcher]

i like it but 1 problem does it melt in the summer?

[jackcday]

That would have to be bloody hot - 2600°C to be exact.

[dome_head]

It does get very hotin Houston, but I've never seen concrete melt.

[cd41]

If i ever see concrete melt in the heat i better be close to death and/or on a massive amount of drugs

[mg0930mg]

haha, why would it melt?

[Berkin]

Maybe you could melt concrete if you used a plasma torch... I'm not sure...

[mg0930mg]

I don't think it could.

[Berkin]

Would instant concrete, the powder that comes in 60lb. bags work for this?

[omnibot]

Cool!

[Wolfrick]

Questions: How much concrete was used in this project? Did you use premixed concrete (dry, by-the-bag)? Or did you have readymixed (wet) concrete delivered by truck? Did you use a motorized mixer to keep it from going off while working? How did you finish the inside of the structure? Or did you leave it rough? Thanks for posting this. I need to build two or three of these!

[PKTraceur]

Its "CEMENT," not concrete. I've been reading tthe comments, and many people made this mistake.

[mg0930mg]

However, the guy in the instructable did say concrete in step 2

[TheTrueZeRO]

LOL thats cool

[Full Frontal Graphic]

Nice. I could see making one that looks like a boulder, so it is part of the yard decor.

[dardley1]

I would like to make a semi-flat fish shape; what concrete mixture and proportions should I use? I tried it with a recipe using sand, but most of it fell apart.

[kirnex]

Typical ferrocement recipe: 3:1 sand to portland cement (not concrete), and enough water to make it spreadable. For a very strong ferrocement, use a 1:1 ratio of sand to cement.

You should be able to squeeze the mixture in your hand without having it fall apart, or having water drip off it when squeezed.

Hope this helps.

[dome_head]

Start building the wire shape using the hardware cloth, cut like the attached template. The base should be as long as the circumference of the base of the doghouse. The height will be about 1/4 of that length. So you end up repeating the template four times. Try it with cardboard first to make sure you understand how it works before you cut the hardware cloth. Once cut, fold the points over and around to make a half dome. Imagine the longitudes and latitudes on a globe. Bend loose wire around to connect the seams. For the chicken wire layers, just wrap it around a few times to get a dense mesh. Put the half dome upside down on the garage floor and walk on it to get the wire mashed together good. Use steel wire like sewing thread to lace around the dome to pull in the high spots. It does take some time. Also use short lengths of wire like tie wraps to pull the mesh together into a dense layer. Cut the door opening in such a way that the excess material will form the door collar. Lace that together into a dense mesh also.

[dome_head]

I said half dome a couple of times. I meant to say half sphere.

[Whaleman]

perhaps you are obsessed with domes, eh dome head?

[kirnex]

Ferrocement is a 3:1 sand to cement (not concrete) ratio. Would have been good to mention this in your instructions.

[BOOM5601]

I'm am going to test this for strength with some flash powder bombs. If it can stand up to 5, its above average, if it stands up to 10+ it would be extraordinary.

[TheMadScientist]

thanks much for the instructions, was very helpful in making an explosives containment center, which not only made me happy, but my neighbors were pleased with the fact that my devious experiments were somewhat contained

[rimar2000]

Very nice. I was made successfully an "pagoda" barbacue chimney with this method.

[steven07]

Add a wire mesh floor , door and you have a Faraday cage protecting your dog from harmful rays too. nice instructable

[StepsoftheSun]

Hahah

[bethehammer]

The beauty of this, if you live in a hot place like Arizona, it will stay cooler inside and give your dog shelter from the sun.

[tjb]

If you want to work up a "flat" structure, you start with a pink styrofoam shape held with wire mesh and coat it with the cement/quickcrete. Makes for great insulation properties and a bit lighter, so easier to move if necessary.

[boylason]

Dunno about that thing withstanding hurricanes, tornadoes, etc. but what good will it do if it's up in the air? It does seem like it can absorb shock pretty well but did you ever think of anchoring it?

[TheMadScientist]

hey, could this be used to make an explosive testing apparatus? adding a few layers of plexiglass or bulletproof glass to make something resembling a microwave?

[cooy]

you should make a more modern shaped dog house so he will be the envy of the other nabors sorry i suck at spelling (real bad)

[stkrzysiak]

Uhmmm, something about your dog seems familiar. Take a look at my dog.
http://profile.myspace.com/index.cfm?fuseaction=user.viewprofile&friendid=85517856
I never thought I would ever see a dog that resembles mine.

[SmartAZ]

Yes, this works well. Use many layers of chicken wire until it's an inch thick or more and tie the layers together until it rings like a bell when you hit it. Then just stuff the mud in using rubber gloves. Forget trowels, this is a hand job. You'll need about 50% more mud than you calculate. You have to do the mud all at once, so larger structures require a lot of manpower.

[Drew_Blood]

I appreciate you posting this. I've spent a fair amount of time looking into mid-sized ferrocement building (sheds, etc) but when looking into a doghouse it never occured to me!

[bornfamous]

Looks like a good, fast way to build a cheap house for people.

[_soapy_]

There have been plans to use inflatable forms and then spray the concrete over them, letting it set, then deflating the forms, leaving a solid concrete shell, for emergency housing and stuff. Obviously without the chicken wire, though. You could use a similar plan for things like making a giant boat for emergency housing after hurricanes, too!

[senacharim]

Such houses/structures have been built.

[bowakowa]

Do you know where I can see examples?

[Drew_Blood]

www.monolithic.com has lots of information about this style of building on a large scale.

[blksheep]

Nice project. Could be used to do all sorts of small, outdoor containers. Make it bigger and your kids could play in it.

[norml]

It would probably make a good wood fired pizza oven if it had a vent in back, brick floor etc.

[trebuchet03]

Just wondering... and its probably just semantics... If concrete is a mixture of cement and aggregate/sand and ferrocement is a mixture of cement and sand over wire. is ferrocement simply concrete over wire? Theme parks use this method a lot when building complex natural (or unnatural) scenes -- just on a tiny bit larger scale :P

[Ian01]

Ferrocement sounds more like cement mixed with iron filings or something like that.

[dome_head]

Sounds reasonable to me. I wonder why they don't call it ferroconcrete? Maybe to distinguish it from the more common concrete with embedded rebar.

[westfw]

Do you suppose that you could add more details about the part where you construct the chickenwire frame? It looks like that's where a lot of the difficulty shows up, and it looks very much easier said than done...

[blog.darkforestdesign.com]

This looks like cool stuff - strong if it can withstand the likes of Frisky and small tonnage nuclear detonations, to be sure. Could you give some more info on what kind of structure you used beneath/inside it, and how you applied it? Is it messy? Can you get it at your local Home Depot/Lowes?

[dome_head]

No structure underneath or inside. It is a free standing dome. Just chicken wire and concrete. Huge free standing structures like airplane hangers have been built using ferrocement. Google ferrocement to get many good links. Use one part cement to 3 parts sand. Use just enough water to moisten the mixture. Use a trowel to apply. Just slap it on and work it in. Wear gloves as wet cement will irritate the skin. All materials are available at Home Depot. This is not rocket science, but it is messy.