Need help with floating shelf stability

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Forum topic by MRod posted 06-23-2009 04:46 PM 4176 views 0 times favorited 8 replies Add to Favorites Watch
View MRod's profile


74 posts in 4057 days

06-23-2009 04:46 PM

Topic tags/keywords: floating shelf shelves

Hi LJ family,

Can you please provide some feedback on the following project questions:

Am I crazy to think a shelf that is probably 40 lbs on its own can float with anchors into drywall? Will two 4’ shelfs butted next to each other work better?

Should I be using different materials?


Project Requirements:
- 8’ long shelf
- about 7’ off the ground.
- display shelf for 1lb coffee bags
- Desire to have shelf float
- Shelf should be 2” thick and 10” deep

- The wall has either metal or wood studs. Not sure
—The wall is painted in a custom color that I don’t want to poke a lot of holes into to see if the studs are wood or metal

Torsion Box
- 1/2” Oak Hardwood Plywood for the top and bottom
- One – 2” h x 1”w x 8’ l piece of Alder for the wall support (a bit lighter than than oak)
- One – 2” h x 1”w x 8’ l piece of OAK for the front facing vertical piece
- small alder pieces in the middle to make up the strength

Dry fit picture here –
Floating shelf dry

Thanks for the help!

-- MRod, Henderson, Colorado by way of Brooklyn!

8 replies so far

View patron's profile


13603 posts in 3335 days

#1 posted 06-23-2009 05:15 PM

i just used some new ” butterfly type dry wall anchors i got at ace hardware .
they are a t type with long side (2) ribbons and a sliding outside holder ,
you drill a 1/2” hole in sheetrock and slide the base in and it flatens behind wall,
then you slide stopper down ribbons and push it tight by wiggleing it as you pull on ribbons .
it goes flush to wall face , and then you just snap of the ribbons and you put the enclosed machine screw
with whatever clip holder and tighten it in anchor .
they make then in various holding powers , VERY EASY .
they go from 3/8” to 31/2” adjustment .
if you hit a stud just use a regular screw in that spot .

-- david - only thru kindness can this world be whole . If we don't succeed we run the risk of failure. Dan Quayle

View lew's profile


12052 posts in 3749 days

#2 posted 06-23-2009 07:37 PM

With a shelf that long, you will probably span about 4 studs. A cleat, lag screwed to the wall, should be more than enough to support the shelf. Make the cleat out of a 2 X 4. Make the lag bolt holes in the form of short slots to allow for leveling. 1/4×3” lag bolts will be more than sufficient. A couple of #8, 1 1/2” screws thru the top- into the cleat should be all you need to fasten the shelf into the cleat.

-- Lew- Time traveler. Purveyor of the Universe's finest custom rolling pins.

View MRod's profile


74 posts in 4057 days

#3 posted 06-23-2009 08:32 PM

Thanks guys. Patron, I picked up the butterfly anchors today. I will use Lew’s idea to create a slot for the anchor bolt for leveling.

Lew has a good point that there will be at least 4 studs that I should hit. My concern is that if they are metal studs I won’t get a good hold, aren’t metal studs hollow?

I’ll do a test to see if there metal, if wood then I’ll go with lag screws instead.

Thanks guys!

-- MRod, Henderson, Colorado by way of Brooklyn!

View BigAxe's profile


32 posts in 1665 days

#4 posted 09-05-2015 02:31 PM

For that weight you have to anchor your shelves into studs.

View ChefHDAN's profile


1062 posts in 2844 days

#5 posted 09-05-2015 02:55 PM

Tricky thing with the snap toggles if you’re dealing with an insulated wall. I did a shelf project and the walls were so tightly insulated I had to fight with every single one to try & get the “in-wall” piece to lay flat to screw a bolt into, managed to get almost every other one to work and used 50# screw anchors for the rest.

If steel studs, you can get self tapping screws designed for steel stud assembly. They are very common and no prob at HD etc. another thought could also be to see if you could set the snap toggles in the steel stud, which IMO would be near bulletproof, but perhaps a fussy PITA

-- I've decided 1 mistake is really 2 opportunities to learn.. learn how to fix it... and learn how to not repeat it

View runswithscissors's profile


2750 posts in 2019 days

#6 posted 09-06-2015 02:39 AM

A magnetic stud finder should quickly tell you whether you have metal studs.

-- I admit to being an adrenaline junky; fortunately, I'm very easily frightened

View Daruc's profile


460 posts in 1127 days

#7 posted 09-06-2015 03:02 AM

I don’t think your 1” cleat is enough to handle the leverage of the 10” shelf.
Maybe if your shelf was 3” thick with a 2” cleat would be better.
I did these shelves with just a cleat, they’re only about 5’ long.

I used panel adhesive on my cleats, put them on the wall (into studs) and let them set up for a day before putting the shelves on. I also used panel adhesive along the back edge of the shelf when I attached the shelves with nails into the cleat. Another trick I do to keep them level, is cut the back edge at about 2 degrees so that they angle up a tad. Setting up, and over time, and with weight on them, they will come back to level instead of drooping down. Just something I do that works for me.
I would also prop the shelves up, after attaching, until all the adhesive has set up, over night at least.

If it were me and you wanted to keep them 2” thick, I would drill steel rods into the (wood) studs and set the shelves onto the rods. I don’t think your cleat will stay on the wall with only sheetrock anchors. Maybe with the panel adhesive they have a chance

-- -

View TheFridge's profile


9444 posts in 1480 days

#8 posted 09-06-2015 03:05 AM

Metal studs are hollow. You could toggle bolt them too. Hit every stud you can wood or metal. If the space has a drop ceiling then push a ceiling tile up and take a look at the top plate.

-- Shooting down the walls of heartache. Bang bang. I am. The warrior.

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