Successful Green Pea litter system for bunnies may be cats and other small animals

I gave up on the Green Pea system because it was difficult to clean thoroughly. But it was much worse when I went back to disposable litter. The pellets are gone from the pet store shelves. The remaining have some have sticky residues and made a mess with bunny's tail. I ended up on the top quality paper litter. It's expensive and still I have to change often to keep bunny dry and clean. Over $10 a week just isn't right.

From avoiding pollution during engine oil change, I got the idea of revolving cleanliness. Say you use the same used oil tray every time and you don't ever need to wash it clean with detergent. Say after cleaning some spills, the floor is cleaner than before and you don't normally go there, that's clean enough, until next time.

For my modified Green Pea system, you just need 3 trays that can stack close together, and some sort of screen as in screen doors. And the main ingredient is aquarium gravel. And you also need some duct tape.

The bottom tray is unmodified to hold liquid.

You drill a lot of small holes on the middle tray such that gravels rarely get through. These holes are to drain water after rinsing. The number isn't important but affects the speed of drainage. But the holes should be placed such that water do not pool on the corners, the sides or the middle. A little pooling also not important. Then you put 1 to 2 inch of aquarium gravel on this tray. They support the weight of the bunny and allow liquid to drain to the bottom.

For the top tray you cut off 1 to 2 inch off the bottom, a height approx equal to the thickness of the gravel. Replace the bottom with a screen. I use those for solar screen door. Tough, flexible and soft. I duct tape it to the outside of the tray. I tried to super glue it but not successful yet.

That's it. You need two to three sets for rotation.

For extra credit, if the stacked height is too high for baby or old bunnies, you can put off parts of the wall in all three layers to let them in and out easily. A shallow tray will do, one to two inches. But usually trays are deeper than that.

So, the bunny do it's business on top of the screen. It's weight is supported by the gravel. Any solid or pill will stay on top without going into the gravels making them difficult to clean. If some solid sticks to the screen, you can sprinkle some paper litter to keep clean. You can just lift the top tray off with the screen to empty it as often as you like. Liquid will go into the bottom of the gravel layer.

Bunnies like gravel. He likes to dig a shallow depression and rest in it. Pea gravel from hardware store will do but smaller ones should be more comfortable. I suggest white angular gravels from aquariums but not too fine. You can easily see how dirty the white gravels are. Angular ones stack as in paving well while round ones slip around the feet. Indeed he sleeps on the gravels a lot of times, more so with the soft clean screen on top.

To clean, solids are simply emptied from the top tray as often as you like. Each day you need to soak the screen tray on top of the bottom tray a bit. Then it's easy to rinse it clean of sticky solid with or without a moderate pressurized nozzle.

The gravels just need to be rinsed. You can pour out the top water and let the water drain from the bottom holes.

It's not easy to dry the gravels thoroughly. The sun dries fast but only the top that it sees. I tried to bake it in the oven. It would work but you need a big oven ware. The gravels also have to be relatively clean, free of pills, so that the smell reminds you of cooking rather than the bunny.

This setup is designed to dry the gravel in place. With or without the sun, the gravels at the top will dry fast. So three sets of gravels are enough for a rotation. After enough drying, you just put the gravel tray onto the bottom tray and put back to use. The gravels may not be completely dry, but the top layer is dry, drier and cleaner than the last batch that the bunny did his business the day before. In comparison, if the gravels are not completely dry in the oven, you will feel the wetness when you pour them around into the litter tray.

In my last version, my two problems are that too much water with dirt goes into the outdoor laundry sink. If I use it to irrigate, the pills are fly magnets.

This time I just use a small patch of gravel pit outdoors to clean and drain. Since the pills are separated and the gravels have relatively little dirt in it, I just pour the dirty water down the pit for irrigation. The gravels will help to trap the tiny dirt down there better than bare soil. Everybody and the plants are happy. The liquid waste I pour as far away from plants as possible. And with a lot of water to dilute, I hope the plants are OK with it.

The running cost is the very few gravels that are lost everyday, and water. The water consumption I would say is about a flush of the toilet. I think I can use a lot less water if I try. It's revolvingly clean as long as the gravels don't smell. The top gravels will be relatively clean.

For cats, you can't have the screen layer. The gravel lost will be greater when you scoop out the solids, but you can use cheaper hardware store gravels.

Small creatures like to live in the gravels. So you may want to dry the gravels high up on some stands. There are plenty ways to clean the gravels thoroughly once a while. Many germs die at 60 C for a minute or so. (please check). So pouring boiling water on the gravels and soak them until the water cools will do nicely to kill a lot of things. Bugs will do poorly than germs. You can also use chemicals like hydrogen peroxide, salt, baking soda, vinegar. Bartender's friend is a rather strong acid but organic. Just don't eat it or let it absorb into your skin too much.

Even if the duct tape isn't secure, they don't come off that easily during cleaning, and the whole setup is rather neat when stacked on top of each other. Let me know if you have ideas to get rid of the duct tapes.

Green Pee Litter Box II (for rabbits)

I gave up on the Green Pee system once. I figured out dry is the way to go and you can throw away the trash when and how much you want.

I tried different dry litter and finally back to square one, the high quality plain white paper litter, that expands 3X. I had been running away from it since day one. It's about the most expensive type commonly available. I tried most others. Now my bunny is a bit old to clean himself thoroughly so I have little choice.

The problem is, the litter box is so good that he sleeps in it too. And pee outside the box. And since he can't keep his feet dry outside the box, he pee inside the litter box too.

It's not lack of training or he is hard to train. When he was a baby he just pee on the tiny corner litter box. He kept going when he was a lot bigger, even when the box can barely allow him to sit down.

Now we just want to make it comfortable in every way, and now he lives indoor.

We just can't have his "cage" all covered with expensive litter. And how to clean it? He pees like a facuet.

So we went back to the Green Pee system and see what we can improve. Gravel is less messy if he pees and sleeps in the same place. And we can surely afford to cover the whole cage with gravel.

Now it looks like this. The litter box is two simplest cat litter box stacked together. The top one has some small holes at the bottom for drainage. The bottom hold any liquid passes from the top. The top litter box has inside it a layer of aquirum gravel, or substrate. On top of the gravel is a screen to reduce dirt or pills to get into the gravel. We use solar type screen for patio screen doors, which has a thick plastic coating on the screen wires.

Bunnies like gravel. Given the chance he will dig a shallow depression and hug his body in it. But earth and sand are similar. Just that gravel is easy to clean. Cool too.

My previous mistakes include thinking that the gravel must be completely dry before next use. For this 2nd version, the bottom box is taken away for the gravel to drain through the holes after rinsing. After overnight draining and an hour or two under the sun, the top gravel will be very dry and comfortable. Here we don't worry about humidity.  If the gravel isn't that deep, almost all will be dry except for some on the bottom.

Last time I used pea gravel from gardening stores. They are bigger and less comfortable to sleep on. The sizes of gravels vary a lot. Indeed I use a sieve to collect smaller gravel for the litter box.

Aqurium gravel or substrate are much finer. Some are not a lot bigger than a grain of sand. It's a lot more expensive than pea gravel but you don't need that much. About 10 lb for a litter box.

Some still wet gravel on the bottom doesn't matter, as long as you don't turn over the gravel. In version two, the gravel drains and drys in the litter box. Once done the litter box is put back for use plus the bottom box to hold any liquid. The gravels aren't moved once the top are dry.

Acquarium gravel seems to dry faster. Because it's finer, you don't need that much.

The other mistake is thinking that you need something to absorb the pee. The pee can stay on the bottom of the gravel, and held by the bottom box. So the system is very simple. But you need to clean up everyday, which is rather simple. You can also put something at the bottom to absort the pee, like kitchen towel and baking soda.

I thought cleaning was easy after soaking in some powerful solution overnight. It was the other way round. The more soak, the more is the time wasted for drying. And it is messy.

Now the cleaning is just take away the top screen. Rinse the gravel in the litter box. Pour away the floating dirt. Rinse the bottom box.

It's seems that the gravel are lighter so it's easy to rinse clean. And you don't need that much to be comfortable to sleep on and hold enough pee under.

The screen can be cleaned using thin jet patterns coming out of a garden hose.

I clean everyday and have two litter box system for rotation. I can have 3 if needed, less than $10 each.

The problem of washing is that rabbit poop is top fertilizer but attracts flies. So unless you have some sort of draining pit outdoor that flies cannot get to, you need to deal with the waste water. I have a big outdoor laundry tub and I can wash things in it.

Fault tolerant vacation automatic pet feeder

Finally, I made it. I went on vacation for a full week and my bunny survived. Though I have a pan and tilt cam watching if anything went wrong.

Those on the market are too expensive. And even if I get one I don't trust them. First, they have a single motor. Auger / screw types can jam. If the motor fails, all meals will fail.

I actually built a multiple meal automatic feeder for my dog. It was complete with a hacked digital timer, and low level logic chips like NAND gates. I did that because I always have about a week to design and build it. And it have to work. The problem is, the motors are too expensive, or I couldn't reliably mount them to "open doors". So I only tested it for a weekend or two before he rested in peace.

At the time I hardly know what is a servo. And after I came across it, I just didn't have time to learn the hardware and software of a controller to drive them. And how much 7 servos cost? I used the cheapest motors and they work fine. The problem is that it's hard to glue some latches to the bare motor axle without gears.

This time around it's different. Tiny servos like sg90 cost next to nothing. Arduino kits are cheap and you can do a lot of other things with it. You order it from Amazon and they came quick enough before I setoff for vacation. I hope it's plug-and-play as they claimed. But I saved some money by ordering from other sources. So it's not plug-and-play but I figured it out how to program it.

I'm sort of a hardware and software professional so the rest is easy. The software is supposed to be simple, just wake up everyday at the same time and turn on different motors. That's why I actually built one with discrete logic that could be more reliable, and worked first time. But I don't trust a cheap controller working outdoors. One power outage or interruption the controller can be trapped into non-operational states.

I was prepared to write and test complicated software so if power is stopped for an hour, the operation behaves as if time has been lost for an hour or two, not whole days and not skipping meals.

After more thinking than coding, I realized it's best to drive the Arduino with a digital or mechanical timer. When the Arduino has stable power, it only need to use one location to remember which motor to turn on. The software is real simple. I was preparing to work overnight to make something work reliably. With this simplicity, I just needed trivial modifications to the sample code. There's only a few "critical" lines so I can tested them thoroughly in no time and went to sleep before leaving early the next morning. So to fail the timer has to fail and the board hardware has to fail. They seldom do.

My designs has been for the servos to open something like a trap door under food, and so all the food fall down to a tray. And I have no time to make the custom containers.

What I did was building a see-saw with fat lolipop sticks, with a cup of food on one end and a servo arm on the other end. When the servo turns the cup will drop. Everything is made of fat lolipop sticks that you can find in craft shops, and school glue. They are a surprisingly fast and secure combinations. To guard against earthquick, bigger animals and an angry bunny shaking the pet house, there are little slip guards also made of strips from wooden sticks and the cups are stabilized by cup cake paper liners. The craft isn't too bad but I have to build ad-hoc guards and defences to defend against bigger wild animals and the weather.

Wooden sticks was a surprisingly good choice because you can stack them up with glue to your desired height, or stick them to square dowels, also from craft stores and also hardware stores.

All the wires from the servo, 21 of them, are not soldered, but using the wires from the kit that plug directly into the Arduino board, and also use the tiny development board for the 5V and GND distribution. It doesn't matter if the wires fail to contact. Only one servo will be affected by one circuit failure.

And to ensure a good drop, the first thing was to custom built a big tray and inclined walls for the pet house. I had sewing threads glued to the cups and sticks to ensure they fall as expected but not into the tray to confuse the bunny.

The see-saw isn't the best design but I picked it because I had no time for other things. A long see-saw can balance out a heavy cup if the servo is weak.

As seen in the picture, one of the cup didn't drop. But there's only treats in the cups. There are plenty of other pellet food and hay that the bunny doesn't eat that much unless he has to. The problem was that the little vertical slip guard wasn't vertical enough. So the see-saw stick was trapped. This was a known problem in one or two of the unique handmade mechanisms. I forced the little glued sticks sections apart until it was smoother for the see-saw stick to drop. But one of them revert to the bad position eventually.

I almost built a automatic flush toilet too using the Arduino with servos. But it's too risky first time so the flush was driven by the lawn sprinkler controller for now.

Validation of the Green Pee litter system for rabbits (and cats)

The modified Breeze litter system

The homemade Green Pee litter system is designed for cats, with ideas from the commercially available Breeze system.

The Breeze is one of those products that give away good, tested ideas when people can make it for next to nothing.  And if you promote it too much, it will affect the profitability of your other products.

First, the Green Pee is two stacked trays.  The top one has holes in it to drain liquid waste, and pea sized gravel for cats to cover their solid waste.  The bottom tray collects liquid waste and allow you to put in anything you fancy to deal with the odour and ultimate disposal.  You scoop away cats' solid waste on top, and sacrifice some gravel to go with it.  You have to maintain the level of gravel with new additions and the old ones are supposed to be rinsed and dried from time to time.

The Breeze that inspired Green Pea is the same thing.  The top tray has a plastic grid on most of the bottom for drainage.  The grid maintain the strength of a fairly large tray, some 20" by 12" (check spec).  The bottom tray is securely snapped onto the top, but has a drawer like tray in the middle that can be pulled out.  The tray just fit a custom sized pad with probably very absorbent gel.  The drawer is very shallow but will allow the gel in pad to expand a lot and hold a lot of liquid waste.  Instead of gravel, Breeze has it's own pellets that is perhaps made from soft rock with a waxy coating.

I got the Breeze just because I wanted to use disposable pellets that I liked - feline pine.  The slots will work better than drilling holes.  And that the feline pine's own double tray system, very similar to both, is only available online with expensive shipping.  The Green Pee is better, and cheaper.

The other reason I got the Breeze is because I was obsessed with adapting to rabbit use, getting rid of the pills / pellets / pebbles in a convenient way.  Unlike cat waste, the pills are the same diameter as typical pellets, so you can't scoop or filter them out to reuse the pellets.

It turns out that for rabbit use, the best adaption is nothing.  When you rinse the gravels, the pills will float while rocks sink.  You just pour away the pills and flush it, or pour the pills into a sieve / colander to get rid of the water, then dump the pills in trash.

Some people put a semi-rigid screen on top of the gravels to prevent the pills from mixing with the gravels.  You scoop away the pills from time to time.  That doesn't save much work because you need to wash the screen at least daily for the semi-solid waste.  And you need to wash the gravels anyway.

My particular problem is that the screen on top of gravels is too comfortable.  My rabbit occupied it as his bed and pee on his normal sleeping area.  Without the screen, he still likes to sleep on the gravels and pee on the corners of the tray.

I see no advantage of the Breeze pellets to gravels.  The regular cylindrical shape of the Breeze pellets may drain better, and the coating may reject water and therefore odour.  But I don't see any problem of using pure rock instead.  You can use finer gravels for you rabbit if you worry about their feet without pads.  There are very smooth and exotic aquarium gravels, but for a few dollars I get a huge bag from gardening store and filter out the larger than 1/4" stones with a discarded potting tray with a grid bottom.

As for what to put in the bottom tray, newspaper and baking soda is excellent I'm sure.  If you can get the huge baking soda box in the laundry department (non-food grade from the same manufacturer), it's much cheaper than from the baking department.

My problem is, I don't have any newspaper.  But even though the Breeze has a tiny tray, you can still put a lot of other stuff in it that will last you about a day or two.  If you only want to empty every week, you just need to put the Breeze on another tray and get rid of the drawer.  You can put crumbing cat litter and scoop away the crumbed solids.  But they are not that environmental friendly.  You can put anything absorbent down there and let nature equalize the liquid distribution.  You can put biodegradable gel for camping but that would be expansive.  I put in feline pine because I have some left.  There are similar much cheaper pellets but not in my town.  The pet store do have some pellets from recycled paper that are cheaper.  In general compacted pellets are more absorbent than other loose materials.

To convert a Breeze into a Green Pee, I put a screen on the grid, under gravels.  Some of the gravels are too fine and fall through the grid.  So far I keep the drawer system because it's a piece of cake to empty every day.  People use plastic canvas from sowing / craft stores for the screen that you can cut to size.  I use bug screens or those for windows and doors.  I use the thicker ones that seems to be weaved from nylon threads and coated with plastic.

The reason I gave up on pine pellets is that you have to keep paying for the consumable.  You can't separate the good pellets from the pills.  You need to keep adding fresh pellets so the degenerated dust will not stick to his feet and being carried around.  (This is minor.)  The Breeze drawer is too shallow for the pine pellets.  And you have to use a scoop to "encourage" the wet dust to go through the grid and down to the drawer.  The dust should fall through by itself but fresh pellets and wet dust can accumulate to a thick layer and it gets harder for the dust to fall through.  Feline Pine's own system may be better but I don't see how the problems are totally eliminated.

The only problem is drying the gravels.  You need two or three sets to rotate.  And you need a yard but can be done without one.  Pouring away the pills, soaking the gravels overnight will allow any dirt to rinse away the next day.  If you have space, spread the gravel into a single layer and sun dry.  If they are completely dry, you are not creating an environment to accumulate germs.  Germs cannot survive without water.  If you feel the need to disinfect anyway, household beach is effective when you soak the gravels.  But it is not environment friendly and can be harmful.  Germs that survive on animals adapt to neutral pH or 7.  You can kill germs with extreme acid or alkaline.  Vinegar can kill many germs.  If you buy citric acid crystals you can get more acidic solutions.  Washing soda should do too but vinegar is safe because you can eat it.  Baking soda is a weak alkaline so it cannot be effective.  You cannot mix acid and alkaline because you will neutralize them and become useless.  Alcohol and hydrogen peroxide are effective but because of the cost, they are only limited to small surface areas.  For Vinegar or Washing soda, you need to consider the concentration level.  If you can, check with cheap pH papers to get less than 4 or more than 9 for sufficient concentration.  But since washing soda is so cheap, I would think it is easy to be alkaline enough. 

Miracle liner for pet cage and anything else

The miracle liner is polyester film such as Duralar.  It's like a sheet of paper but made of clear plastic instead.

The miracle?  It's easier to work with than paper.  It is tear and scratch resistance.  It stays flat, better than non-slip.  It's heat resistance and chemical resistance.  It's low cost.

Even if you brought a huge roll, it stay flat when you unroll it.  I know because I used it to cover the whole dinning table.  It's clear and you can write on it.  You can put it on a table or on the floor with a grid pattern on it.  It's extremely easy to align and measure the exact size.  Or you can trace the outline of the cage, or you can just cut freehand until the sheet fits the cage.
 
The sheet is slightly too thick for a paper cutter.  But it's extremely easy to cut with scissors.  It's easy to cut while following a straight line.  It's easy to make a smooth cut whether you cut is straight or slightly curved in multiple parts.  And since it's clear plaster, it's hard to notice that the cut is not perfect.

If the cage floor is reasonably fitted with a sheet from wall to wall, it's very difficult to take the sheet off because it stays flat from edge to edge, corner to corner.  My bunny toss everything and attack steel wires but he couldn't do anything to the sheets.  If the cage has some sort of "wall", it's better than non-slip liners.  It just couldn't slip pass the walls.

The sheets are extremely easy to clean.  I used rigid sheets before such as acrylic.  I have to soak them in acid to get the rabbit poop off.  It's a lot harder to cling onto flexible plastic sheets.  When the poop are dry, they will almost fall off by themselves.  Chemical free.  I suspect that there is something to do with it's diet and the strong sun.  In any case, this material is the most easy to clean stuff I ever used.  It will return to it's flawless clear state after cleaning.

Because it is cheap, I stack several of them.  It's non-slip even when stacked together.  When the top one gets dirty, I just lift it off and expose the 2nd sheet.  Then I dry the dirty sheet in the sun.  If you want to wash it clean immediately, you need some acid such as vinegar and citric acid.  Or, you can wipe the poop off with tissue paper whenever you see them.  It's almost perfectly clear again once you wipe it.

The sheets are slippery so the naughtiness of the bunny is reduced a little.

My cage floor is made with perfectly pre-cut to size wood pieces.  Polyester sheets are the perfect liner for that.

Perfect low cost custom pet houses

You know I have been building things to improve my bunny house.  The last time he was living in a concrete block bunker with a big grass yard to himself.  That didn't solve all the problems.

I was going to custom made an acrylic house with all the easy to maintain gadgets.  It would be perfect for indoors and outdoors and while we are on vacation.  It was never done because the more I think, the more it's impractical.

Acrylic is expansive and you have to be precise to glue pieces together.

I have been building small PVC gadgets for a while and it suddenly dawn on me why I don't try to build a pet house from scratch.

I have been building very precise PVC pipe structures using only standard tee's at less than 30 cents a piece.  PVC pipes are virtually free - less than $2 for 10 ft.  With the help of a spread sheet, I can build very complex structures.

For pet house, the first problem is the floor.  You can use pipe grids as the floor but still you need something to cover the gaps.  You can use pipe grids for the walls but the total cost of tee couplings can be high, even at 30 cent a piece.

Wood is still the best choice for the floor.  This bunny house is for indoors so I paid for a premium board, so I can nail ready made side guards on it to prevent spills.  The board has to look smooth for indoors and can be painted if needed.  For outdoors a flat particle board will do.  The wood pieces are of standard dimension so I don't need to do any precise wood work (I can't as I only have a jigsaw).

For the walls I use 24 gauge galvanized steel wire forming a 2" grid.  It turns out to be a great idea and looks neat too.  It's easy to drill small holes into PVC pipes with a plastic bit.  I sand the holes briefly with an oscillator tool.

It turns out that it's easy to tie the wire onto the pipes and tighten them.  If you go around the same holes twice or more around the pipe, it will be securely attached.   Add a Cirus clip on the endpoint and you can secure it further.  After you tighten a length of wire, you can keep the tension by Crius clips as in the last post.  Then you continue to wire and tighten the next part.  You can wire the entire structure without one single wire without breaks.  But for modularity I wire only one side at a time, and use separate wires for vertical and horizontal.

This bunny has been known to attack chicken wires and succeeded.  He had a go on the steel wires but can't do anything to it, yet.  Because the wires are hand tight, he managed to put his head through the grid, but fortunately not his feet at the same time.  So, the cage is secure.

This cage is open top with walls two feet high.  But I decided to put in a door so the kids can do the daily chores too.  What you see in the middle is a toddler-proof door.  I still have to add some legs so the vacuum cleaner hose can get under it.  Also, it will be ideal if I don't need to bend down to feed him or clean the cage.

This is 20" by 3'.  I'll build a 2'x4' for outdoors.  It will be higher than the sprinklers can reach so we can put it in his yard without turning off some of the sprinklers.

You can clip anything on the pipes like sunscreen, rainproof sheets, blankets.  The outdoor one will have a roof structure.  You can see the Crius clips in the picture, near the lower left and right corners.

Critter home a success

The modified critter home is a great success, passing the winter flood, storm and cold with flying colors.

The insulation is great.  It's water proof.  And even water leaked from the tiny cracks in the roof, they are still held in place by tapes even when wet.  They don't get wet and still functions, and water didn't drip from the ceiling.

The flaps and magnetic closure were designed to keep warm from cold draft.  It also prevents rain storms that went horizontal.

Well before the severe weather, we put the home on a pile of paving slaps to raise the height.  We can use a big bucket under the litter opening to collect waste in one go.  The horizontal rotating/sliding door works well for it's simplicity.

The raised acrylic platform inside the home is good.  Dirt mostly fall down onto the floor level.  The acrylic platform is kept clean by newspaper on top, fresh every day.

The gap below the platform and above the floor is filled with compacted plastic bags from the supermarkets.  They are pretty warm.

Washing the home frequently is a bad idea.  Too much work and it takes time to dry.  Now the platform is mostly clean, if not you can  pile more newspaper on top for a day or two.  You can empty the dirt on the floor once a week.  The wet litter has to be emptied through the hole daily or every other day if the weather is bad.  Once a month or so I use the steam cleaner to clean the house thoroughly, without moving the whole thing.

The heater using broken soldering iron is good.  It's simple mounting near the top so the critter cannot play with it.  It's shielded with wood plates.  Now that I don't wash and move around the house the mounting and wiring is simple.  It will never overheat.  It may be too mild but a warm wall instead of a freezing wall makes a lot of difference.  You can always use a higher power soldering iron when not in use, taking the tip away.

Improvements: kids can do the upside down bottle, but will wet the place a bit.  Keep the wet area away from the dry area so it will not make a wet mess.  The gaps on the side of the platform could be sealed to control where the dirt collects.

Winterize your outdoor pet hourse

I found the perfect material for adding insulation to my outdoor pet house. Fiber glass is unsuitable because they are for filling cavity that you never touch or breath into. Rigid materials are difficult to cut to size, and do not fit my plastic house with odd corners and odd wall angles. Soft materials are too time consuming to fix onto my plastic walls.

This one looks like some packaging material like packing peanuts. It's like Styrofoam but semi rigid. It's like bubble wrap but it is very dense and the bubbles are not visible. It's cheaper than packaging material - 3.5" x 50' for less than $5.

It's not very thick so it's easy to go around non-flat places. After application it's not bulky so my pet house remains portable, and easy to dissemble for cleaning. It's light weight so I can stick it at the roof with tapes and not worrying something heavy falling down crushing my pet.

It goes very well with sticky tapes. I got clear packing tape 2" x 50m for less than $2. You can tape the insulation to plastic or to other pieces of insulation. Nothing absorb moisture so it will last a long time and the thermal property will not degrade. You can even use it to rain proof something.

The insulation will withstand water and likely steam. The tape may withstand water spraying on it but I'm not sure about soaking and steaming. Washing a big pet house is too much of a hassle. I'll scoop away the dirt and wipe wet spots with newspaper. Occasionally I steam clean the really part. So I don't worry about washing and steaming very much.

The insulation is very difficult to break by pulling, but can be easily cut with a scissor. You can also easily pierce holes in it. I don't feel that big and small pets will want to mess with it. Or, you can always use it only on the roof and on the outside.

The insulation will take adhesive well, such as the caulk adhesive that I use. But I want to rip off some of the insulation in summer, and reuse it the next winter. So I used adhesive tape. If I have a wooden house, I will use staple guns or thumb nails. If you take out the staples carefully, I guess the tiny holes will seal itself.

Because of it's semi rigid property, I can use it for sealing the metal grid door. Leave some extra insulation and it will cover the gaps when the door closes.

For the heater, there's simpler things than my broken low power solder iron. 10W is about right for a small heater. For 110V supply, you need 1.1K ohm resister with > 10W rating. The resister is pretty cheap and so is the electricity consumption.

If you have some cavity to fill, the best and free is supermarket plastic bags compacted. They trap air and do not absorb moisture. I have a two inch high void between the platform and the floor. The bags will get dirty given time. I can just wash them and dry them in the sun. Then use them again or recycle.

A storm proof critter home

How well the new acrylic critter home perform in a big storm? After several days of winter storm, we do the clean up. The critter home is of course dry no matter what. It's plastic in a raised platform that cannot possibly be flooded.

I had Velcro attached to bubble wrap sheet to cover the windows, so that it can be taken off easily like a window. My wife used to tear them off straight away if I use duck tapes - too ugly. The Velcro fell off in the storm, so I have to use the wooden door to cover the open windows. The door was covered by bubble wrap sheet only, without the wooden door.

Some cardboard used to cover the windows fell off. I used tapes on top of them to make them water proof. It's obviously not enough.

Now everything should be hosed off. So cardboard should go. Now that my wife don't tear duck tape anymore, I use duck tape to seal all windows, covered with double or triple layer of bubble wrap sheets.

Cleaning up the sticky poop on the plastic and around the cage is too much work. So I decided that everything should be hosed clean in place. I drilled an opening at the outer cage corner. I attached a 1" diameter PVC pipe as the drain guide, with height about 0.5". Actually I glued the guide before I drill small holes through it and then knock out an opening. The drain will be covered with a 1" PVC cap when not in use. The whole cage is now raised about ground on 2" high wooded frame to accommodate the drain.

The option is to put the drain over a big bucket during cleaning. I may also fit pipes to carry the waste water to some paved area with drainage, or composing hole.