How to build a wall-mounted cat tree 

Not an Engineer OR a mathematician but your logic and process is a good reminder of all that needs to be considered. Very clever and cat-practical design.

You've given me the confidence to proceed with my project. My husband was astonished one day to come home to find I'd changed my entire curtain system throughout a rented house -- 24 windows. He'd bought a drill, and the hardware store wasn't far away . . . I was amazed at myself. But this catification project is 1,000 more difficult. Still, I'll start with three or four shelves and take it from there. BTW, I'm a cat behaviorist. That means I know more about cats than shelves. You need a cat scratching post at least 1.5 times the length of a fully-stretched cat to maximize her health. You're going to have to use more rope or carpet (I advise sisal rope) to cover the rest of your post. Scratching does several things: marks the area with the oils from her foot pads, which soothes her nerves; tears off shedding cuticle on her nails, thus sharpening them; and most important, stretches and strengthens their shoulder muscles. You'll notice that they stretch to within 3" to 6" of the top of the post, then pull their bodies using their body weight to add force and stress. It also loosens their ligaments, keeping them flexible. A cat's clavicles, unlike ours, are free-floating. Keeping that area "loose" is what allows them to sneak through the super-narrow openings that surprise us so much. "How the hell did she get out?" "How'd she get in the closet/suitcase?" They estimate the width of an opening by whisker length/width. They can always get through anything narrower than their whiskers, and usually less, depending on their build. Wily little devils.

Non-engineer here. Wood you get more strength out of the shelf if you made the side boards (boards running perpendicular to the wall) flush with the back board. So you are changing the load on the screws from pull out to shear. Just a thought, I really enjoy your videos. Keep up the great work! Chase

As a fellow civil engineer, I thoroughly enjoyed the statics explanation. Great project too!

I said this before and I say it again: I like your methodological approach to your problems. Your surprise math-attack certainly did add something new to the host of uniform build videos out here.

There should have been a "Math Warning" at the beginning of the video. :) Great project!

The dog at the end looks like he's pouting, like "He never makes anything for me"

I’ve been watching a lot of catification videos lately and yours is the only only to bring up the increased forces of the cat jumping onto the shelves. Thank you!

I'm impressed to see an engineer that can actually build something. It's a running joke in the construction industry that architects and engineers can draw, but not build a doghouse. I'm glad you're more than a "Clicker".

My statics teacher could take a few notes from you on how not to put an entire clasroom to sleep when calculating moments.

I loved the engineering. Wish I would've known how cool that could be back in highschool. I really like the shelves too. Simple and functional.

God bless you! It is heartwarming to see your pretty pets, and how happy they are, and how you did this out of thoughtfulness for them. Wonderful stuff, thank you.

I love it and the cat looks like he loves it too.

I can tell this man is a great person. There dogs has 3 legs. I have been there. I miss my 3 legged dog so much. They are so special!

Cats, shelving, engineering, carpentry, knots... I think we're long lost brothers.

Been a fan of the channel for 5-6 years and just saw this old video. Even 'Young Grady' was fun to watch/learn from. Gonna' have to catch up on all your pre-fame content now ;)

Brilliant! This will surely keep your cat happy as it gives him a place of his own from which to watch all the comings and goings. He won't be stressed as he can get out of the way, and he knows he owns that bit of the house. Lucky cat: loved cat :-)

Nice people. Doggie manners and unassailable kitty food. Well, very thoughtful people. These are things I wouldn't have thought of ....

Where i actively encourage my terrier to chase and play with our cats. I also made a cat tree out of a large limb from my yard.

thats an great idea but i think you could add a cat cave a little hideout for your cat to play hide and sleep

I gave you a thumbs up and was about to leave, but I decided to add a comment. I was very impressed with your engineering statistics added to the video. Most people don't care about such, as long as the video looks slick. I'm adding your video to my favorites because it is worth saving.

Thank you so much for this. We are converting a bus to live in full time, and have 4 cats. I appreciate the math to make sure I don’t do something stupid and hurt my senior guys coming along for the ride. 💜

lol not surprised to find something like this on your channel.

I love that this is in the Civil Engineering playlist. It's so wholesome

Best thing you could ever have with you.

one thing left out was proper use of glue. screws are only meant to hold the 2 together long enough for the glue to cure.

Very talented and creative! Its perfect! Thank you.

Way to go Doc. those were my exact calculations too, with a few short cuts on my part. It's about time we have a man of intellect on hand here on social medias' RU-vid. BRAVO Professor.

Engineering and cats? Heck yea!!

Lucky little kitty !

You read my mind about pull out and force, but I did not have the vocabulary, so thank you for explaining the engineering.

LOVE THIS!! long time fan of the channel and was searching the tube for cat tree vids and found you had made one. Mind=Blown.

Just found ur vid..love it..What a great kitty dad r u😊making those great looking shelves for your cute kitty..I wish I was as handy as u..but..I'm on a mission to get shelves up on the wall for my cute Coconut😊2..they love to b up high..

Gorgeous kitten! And great idea.

Really liked the engineering explanation!

Wholesome and mathematical

I was hopeful that this was going to be: "Wall mounted cats."

Super cute kittens.

Very cool idea and cute animals!

(To the tune of I wish I were an Oscar Mayer Wiener) Oh I wish I were a three legged doggy, That is what I truly want to be, 'Cause if I were a three legged doggy, I wouldn't have to lift my leg to pee.

the rope is plenty long if you flip the wood and have it on the top half! cats like to stretch vertically when they scratch so having the rope on the top half would be plenty

this one's wholesome, Grady!

Hi, I like the technical info because I want to know how h why things work.

We thank you, purrfect idea beautifully engineered.

Nice project, pets, sketches and calculations! Man after my own heart, lol.

I'm not an engineer and I really liked the math. It's great you included it. Can I ask you to elaborate how you got the pull-out force to be >60lbs? I'm familiar with Fsmax = UsN where Fsmax=Maximum force of static friction where if this is overcome the object will move Us is the coefficient of static friction and N is the normal force (mass x gravity). Is this on the right track and then you are somehow accounting for the force applied over the dimensions of the shelf?

Combining my two favorite things; cats and engineering! Great video

Nice idea, I miss my furry pets, but I have learned to really love having fish for pets.

First rate and love the math to explain why it needs to be properly engineered.1

inspired! you've got skills. thanks for the video. I will use this when I rescue in the future

Your cat is sooo cute

Your channel is amazing. Thank you

I love cats and dogs

3:50 love the not! Would love to learn how to do it.

It´s true... dogs eat cats. But they only do it in the wild, when they are in packs. .... I loved your shelves! thankyou.

Good cat

Cute pets you have

Awesome Video! Love the math and physics involved. Looks great. I couldn't tell for sure, did you design the top level as the food station as well? Very interesting idea. I would however separate the water from the food. In my experience cats prefer their water and food in different places. Also if the water is on the top level the potential mess would not be easy to clean up. Just my thoughts. Great project.

Your dog is adorable! :3

Cute video

So awesome 👏 👍😎

Very nice, thank you!

I love you man

nice idea

Statics + cats FTW!

I loved your video because I have two of those, LOL!

Awesome video

Dayuuuuuuum...I just had a brain freeze...too much statistics 😂

I love the videos beginning

Good video, but I was itching to take it off you and fix it when you folded the trimmed side of the carpet *over* the front! Tuck it under the front flap so it can't be seen, especially since your carpet has a one way pattern.

Great vid! Thank you!

I subscribed after watching this video, my first time telling that I subscribed, I blame Mr JonesyBones below :) I want to do this for my two cats, fingers cross. Thanks for the inspiration, was looking at catriss (environmentally friendly cat furniture ...expensive) somehow ended here.

No one wants math problems in a diy cat shelve video!!!!!

LOOOOOVE YOUR IDEA!!!! THANK U!

so refreshing !!! love it!

cat's ownning it

God imagine being married to an engineer. I'm in the wrong degree!

love the math explanation. only thing i didnt like was the carpet pattern

I like it!

Nice idea. I have 2 cats that would love to get away from our lab/retriever.

nice vid

Wish I had the tools for this!

Ya could have just said whack a big screw in for strength , ya didn't need to geek out on us . But nice job . And I want that kitty cat .

I absolutely love your videos, so I hope you dont take offense to my questions. Wouldn't it be more sturdy to just use a few corner plates for connecting the side that is going to be next to the wall? Also, why didnt you use glue to make the carpet adhere better to the wood? Lastly, I think it would be a little more asthetically pleasing to cut the carpet so you cant see any fold-over. Awesome concept though, and I think your cat is really cute.

Excellent...!! Cheers...

I know this is an old video but if strength of the joint was so critical, why not use a more advanced technique of joinery; such as a dovetail?

awww you got a ball for christmas! Anyway. How much resistance force would you assume for two cats thudding on the shelves at the same time? Wish you had shown us exactly what kind of screw you used, and exactly what kind of hole in the wall, and how you attached screws to wall. I'm a newb and still not clear...

I actually like these more than the cat trees, because they are much cheaper to make, requiring less materials.

so what kind of screws should we use? also, no math necessary for the pullout resistance from the wall?

1:37 giggity

Step one: get a workshop with several woodworking tools and a knot tying resource.

How did you attach the rope with the monkeys first to the ledge?

I had 32 cats in my home... :D

You were concerned about pocket screws, then proceeded to use drywall anchors instead of going into the stud??

❤️❤️❤️❤️❤️❤️❤️❤️❤️❤️ love it, thank you

Wow!!, I would love to do this for my cat but she's in excess of 20 lbs and the dog can jump 3 ft no problem, but the cat can only jump 0.5 ft

How is your little Hanko doing now?

Hi, can you please tell me what kind of pen you were using in the video.

Uau!

what is the size of the box?