Cat House




This is a heated cat house that will keep your outside cat warm and cozy all winter long. There is enough room inside for food, water and a bed. Inside the house the water will not freeze even when it is freezing outside.

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Step 1: Start

You may need to train your cat to use the house by feeding them inside. They will see how warm and cozy it is in there and before you know it they will be using it on their own.

We keep our cat houses out all year long but we only feed them inside on very cold days. They are plugged in all winter, day and night. In the spring we unplug them during the day when the weather is warm and plug them in for the cold nights. During the summer our cats dont use the inside, so we put foam pads on top and they love to lay up there. When we turn the houses on in the fall as the days and nights start to get cold again, we find our cats sleeping inside, they really love their houses!

Having fun checking out their new house.

Step 2: The Cats

These are 2 of our cats that adopted us a little over a year ago, Squeaker and Smokey. We do know they are brother and sister and they love each other very much. We made a house for each of them but they won’t use their own, they always sleep together.

They were very neglected and abused by their owners, and then abandoned. When the two of them were abandoned they were both in bad shape, and neither one had been spayed or neutered.

Smokey, he had mats on both his sides so bad that when they were shedding off, his skin was pealing off with them and leaving open wounds that looked like burns. I cut off the mats the best I could, cleaned and medicated his wounds. It took about 3 weeks for him to heal and start growing his hair back.

Squeaker, she was pregnant and close to delivery. I thought she would go some where and hide to have her babies. But I was wrong, on Mothers Day when I came out on my porch I found Squeaker in one of the houses crying and in full labor. She had chosen one of the cat houses to be her nesting box, and that is where she / we raised her litter of 3, two girls and a boy.

When her babies were old enough we got them good homes and had Squeaker and Smokey spayed and neutered. After all this I was worried they might not be close. I was wrong again, they are back to sharing a house and just as close as ever.

This cat house is easy to make and can be built in just a few hours. It is easy to clean and will last for years.

Step 3: Parts

These are the parts you will need to build your cat house:
1 - 100 qt. cooler or larger
1 - super bright 12 ft. rope light
8 - 1" x 1" mounting bases
20 - zip ties
11 - #8 x 1/2" long wood screws
1 - 8" x 8" piece of carpet. Make sure the carpet is a couple inches larger in height and width than the doorway you are going to cut.
1" thick foam pad for the inside bed (cut to fit)
1 rug or blanket for the inside bed
3" thick for outside on top of the lid (cut to fit)

Step 4: Making the House

Making the Cat House

Start by measuring a 6" x 6" square about 1" up from the bottom, in the lower corner of the cooler. Then drill a hole in each corner large enough for a jig saw blade to fit in. Cut the square out.

Mount the piece of carpet to the inside of the cooler with 3 - #8 wood screws, making sure the doorway is covered completely. Then cut a slit about 3" long up the middle of the carpet. This makes it easier for them to exit.

Step 5: Rope Light

Mount the 8 rope light mounting bases with the #8 Wood screws as shown. I tried the self adhesive tape that is already on the back of the mounts and then hot glue, neither one of these will hold, so I decided to use wood screws.

Starting with the cord end string the rope lights around the inside of the lid starting in the lower left hand corner, so the cord end hangs out the back as shown in the picture below. Mount them to the bases with zip ties. The rope light should wrap around twice.

Step 6: The Cord

The cord needs to run out the back of the house, with a jig saw cut a slot the width of the cord in the inside edge of the lid and the top edge of the cooler.

Make sure the lid closes without pinching the cord. Be careful not to nick to the edge of the lid with the saw.

Step 7: Inside

It is best to locate the cat house under a covered porch or at least out of the rain, unless you mount a board to the top that overhangs the door.

If you would like us to build one or more for you, send an email to or visit for more contact information.

Step 8: End

Hey! It's warm and cozy in here!
Please close the lid!

I have placed these under an enclosed porch but others have noted that when used in the open the lid leaks in the rain. So I got a new coleman chest and put it out in the rain and it leaks. Not what I expected. So here is the fix (I hope); I got some weather stripping 1/8" X 3/8" X 10 feet. I put this around the edge of the inside lip. I first tried 1/4" thick stripping but it was too thick. The 1/8" works great I can feel the lid lock into place when closed. It has stopped raining for now so I will get results later. It may be better to put the strip on the lid. I will run more tests when it rains again. Make sure the edge is clean and dry before adding the strip. I used alcohol to clean the edge.

I believe that closed cell type stripping is the best, There is an open cell strip but this may collect water.

The house was in the rain all night with the weather stripping installed and I opened it up this morning and it was dry inside! The weather stripping is a success. It would be a good idea to add a strip about the door to act as a gutter, make it arched or angled for drainage. Also the cut for the bottom of the door should be slopped to the outside. When opening the lid while wet it will help to run your finger around the opening first to remove standing water. This will keep it from dripping inside as the lid is opened.

3 People Made This Project!


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66 Discussions


Question 11 months ago on Introduction

So the Rope Light is what keeps it warm? Even in 40 below weather?


12 months ago on Introduction

It would be very important to mention that the Rope Light to be used for a cat shelter should absolutely be the 'INCANDESCENT' type, even if they are usually harder to find in stores.

Please make sure that this info is totally VISIBLE and UPFRONT, because most people will

mistakenly buy the DEL Rope Light version, which give no heat at all and stay totally cold !!!

That would be a waste of time and money, not to mention that the goal of giving cats a

little extra warmth in the winter would be a failure only due to a lack of info.

Thank You,



1 year ago

Some cooler cat house helpful hints. (1) To locate cooler in the open air, glue heavy mill plastic drop cloth piece to cooler top - hanging over the sides 8". (2) 10-20 watt incandescent bulb is sufficient for both light and heat. (3) For door, cut carpet slightly smaller than opening and glue to door made from mentioned drop cloth plastic - attached to cooler with glue - slit up middle for easier access.


10 years ago on Step 2

commendable that you rescued them. But why not just take them inside all the time, or at least when it is cold out. It is not like they are true ferals. and why the rope light? they don't need it.

8 replies

Reply 2 years ago

my stray is still getting used to us-there is no way I could catch him, hold on to him, and hope we'd all survive.


Reply 10 years ago on Introduction

We have inside cats already and unfortunately they will fight. The rope light is used for heat and reading (if they are in the mood).


Reply 10 years ago on Introduction

Thats too bad, our rescue group has found that fighting is very very rare with anything other than Tom cats who would rather be outside. Cats are communal and usually reach a form of detente.


Reply 5 years ago on Step 2

depending on where u live an the speacies of the rat. they can be smarters than you. but once they an you get to know each other they can be very helpfull as well.


Reply 10 years ago on Introduction

My poor cats have to put up with snakes, dogs, mini komodo dragons and hedgehogs!


3 years ago

Your tips on building a cat house were wonderful! We bought a marine ice chest with 3" insulation (Coleman) on sale. We installed one cat door, but we have yet to close the door because the cat seems fearful of being trapped. We added two strands of Christmas lights ((not LED Lights), and provided a K&H Extreme Thermostatically controlled Extreme Heating pad. I just checked the temperature on the cat house, and it is 73 degrees in the cooler--house when the real-outside temperature is in the 20s in Michigan. So amazing! That's with the cat door open. I moderate the temperature by unplugging a light strand until the right temperature is achieved. I am so relieved to know the cat is safe in the cold northern winter.

We also placed the chest on some limestone blocks so the house is higher than the ground. We added a tarp to protect the house against rain and high winds. We never leave food near the house to discourage predators from bothering the cat. We took everyone's advice into account. It is truly a rewarding gift to help the homeless cat. I didn't pick the cat,, but he somehow picked us... Couldn't have kept him safe without your tips and help!!! Thank you!!!!

Christmas strands.

1 reply

Reply 2 years ago

I can't wait to make one tomorrow! We r taking care of a very skittish male stray that only shows up for feedings - unless he is wandering around at night and we don't know. The weather is bitter right now (12 degrees) and I am worried sick about him. I have heat bulbs in a storage room propped open, makeshift beds, food, water. I know he's eating the food, water, but no evidence he's in a bed. Both beds have the automatic warming pad. Im not sure he has sense enough to try the bed! I'm making myself sick worrying about him. Maybe this new approach will help. Thank you all so much!


2 years ago

Good post! I made this yesterday for our "barn" cat. Am currently waiting to see if she'll use it.


3 years ago

I just built a few of these and came up with some ideas along the way.

First I used a larger plastic tub than the cooler, leaving about 8" of empty tub space next to the cooler inside the tub. I also offset the opening on the tub from the one on the cooler. I had the one on the tub on one side and the one on the cooler on the other. This cuts back on air transfer/wind entry without a flap, although I'll probably hang a little half or 3/4 flap when it gets really cold. I put an old hand towel on the floor of the free space. This lets the cat withdraw to the cooler area when its really cold or hang out in the open space of the tub when its warmer. It also prevents larger predators from having direct/close access to the cat. They'd have to rip the tub open to get them, and good luck with that. I bought a superduty tub/lid from Costco for $9. I had to use a reciprocating saw to cut into it.

My next problem was that after building the first one with a thickwall 'omaha steaks' cooler I already had, I couldn't find anyone selling large enough styrofoam coolers in november. So I picked up some 2" foam board at Home Depot which was a real win...foil on one side and waterproof plastic wrap on the other. 2x4' board was under $5 and I needed two. I cut one of them through the plastic waterproof layer and folded it into the bottom and two sides where the mylar/foil remained intact during the fold, then cut a front, back and top. I put it in the tub and found a cardboard box that just fit the inside, applied a few pieces of tape and it was perfect. No air transfer except for the door and much better insulation than the average 1" cooler. I might get away without a heat source here in northern california where <30 degree weather is unusual. Put the foil part on the inside as it'll retain heat. You can also buy some of those mylar 'space blankets' for about $4-5 or less and wrap those around the cooler for extra waterproofing/heat retention. Back when I had indoor cats I used to put a 2x3' piece of those into a pillowcase and my cats would lay on them as though they were cat magnets.

Next I dug up some polyester fabric pads that reminded me of a 'cat pad' I'd paid a ton of money for. Not affected by moisture, very warm and heat reflecting. This was just dishwasher insulation and only cost a few bucks for a large sheet. I put this inside of an old pillowcase and it fit in a U shape inside the cooler, covering the bottom and parts of the sides. I have a million old pillowcases and they tend to wash up pretty easily.

Lastly, I was worried about water sneaking in the top, although these are under a covered porch. I noticed that I could flip the lid over and the heavy duty tubs I bought have holes in both the lid and cover that let you tie/bungie the lid on, whether its upside down or right side up. I tied it off with a little twine, drilled a hole in one corner for drainage, and taped off the seam with some high quality tape. Now if water gets on top, it collects and drains out of the weep hole I drilled. I could also put a piece of wood on top that overhangs and drill a few holes to twine that off to the lid/tub which would make it even more predator proof.

I faced the door openings away from direct wind towards a wall. The entry is walled on 3 sides. Only really whipping wind from one direction can come into the entry and then it has to do a 180 to get into the main opening, then take a right and left turn to get into the cooler.

The cost of the tubs was $18 for two, two sheets of the foam board was $10, the polyester insulation pads were two for $10. So considering I already had one heavy duty cooler it was about $19 per box. If I could get foam coolers this time of year the cost would have been lower. They should last virtually forever, and even the polyester pads can be hand washed and will last a very long time.


3 years ago

Great Cat House!! FYI for everyone: When using the rope lights for heat, be sure to use the incandescent lights instead of the new LED lights. LED lights do not produce any heat, but incandescent lights do.


3 years ago

It's a good idea to have 2 openings in case, for example, a racoon wandersin. Kitty can go out the other way. A weighted door is good to keep drafts out. Thank you ti everyone who is looking out for the homeless cats! = D. ♥♥♥♥♥


7 years ago on Introduction

I feed an outdoor, homeless cat. I got him a shelter made of large plastic storing crate. It is insulated, and has straw for a bed. Unfortunately, Ginger refuses to enter it. Another cat, who has a home uses it instead. I am very upset. Shall I make the entrance larger? You said place food inside. I am rally desparate. Toronto is known for very cold winters.

1 reply