Securing an inbuilt desktop

[Mark Gibney]

A designer contacted me about making and installing a 2 x 18 x 60 white oak desktop in an alcove.
She does not want to see any brackets underneath.

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I advised her that in the past I have used aluminum angle to attach to the studs and to the desktop, tapered back at the front on each side and painted the wall color.
I also said I have installed shelving in the same situation with screws from underneath angles up into studs, but in this case I'm concerned about people sitting on the desk.
But I think she likes this method.

I could suggest using angle that is secured by removing the drywall and screwing the angle directly onto the studs (drywall is later repaired), and the bottom of the desktop is relieved to seat the aluminum angle.

So, what would you do?
All opinions welcome! thanks, Mark

[Jamie Buxton]

I’d screw 1x1 oak cleats to the wall. I’d cut a 1x1 rabbet along the the bottom edge of the back and sides of the desk. Then I’d rest the desk on the cleats.

Okay, the cleats and rabbets on the sides wouldn’t come the full depth of the desk, so they wouldn’t penetrate the front.

[Cameron Wood]

18" deep you may or may not have a stud near the front edges. If not I would cut in some blocking.

[Jim Becker]

My solution would be similar to Jamie's for this situation but clarifying that the rebates would be stopped. The pieces attached to the wall could be wood cleats or angle iron. In either case, they would "disappear" unless you crawled under the desk.

[Mark Gibney]

Yes, that what I have been thinking too. I guess steel in place of aluminum in that case, cheaper!

[Jim Becker]

Steel angle would be more resilient to weight being applied onto the desktop...like when someone "had a few too many" and sits on it for some stupid reason. The other advantage for steel angle over wood cleats is that the steel is thinner which makes putting in reasonable sized fasteners from below to secure the desktop without having length issues a bit easier.

[Mark Gibney]

Thanks Jim!

[Sam E Miller]

You could also cut a stopped dado and a deep slot on the end of the top to receive the angle. The top would be slid in from the front and the angle is completely hidden. This will only work if the top can slide in from the front so if the back of the opening is wider than the front then this doesn’t work, unless you’re putting some trim peice around the edges to hid the gap. Would look much better for the top to be scribed to fit the wall and avoid the trim.

[Tom M King]

How square are the walls, and if sheetrock, what is the taper on the inside, and outside corners. Typically those are not straight lines. Hold a straightedge against each wall to see. If they are typical sheetrock, the piece will have to be cut to fit each wall very precisely, and hinged down in place, which will limit the possible thickness of the top. It's more complicated than it looks and how it's held up is the least of the worries.

[Kevin Jenness]

As Tom points out, the main challenge is fitting to the opening. Drywall is usually built up at both inside and outside corners so sliding in from the front is probably not an option unless the opening is framed out of square, and hinging a thick desktop into place makes a tight fit difficult. You may want to float the drywall with compound to reshape the opening - that could be done after installation.

A hidden support is easy enough with that thick a top, just rabbet the edges and support with wood cleats or steel angle.

[Jim Becker]

As with many "built in" things where drywall is involved, fitting involves "damaging" the 'rock and fixing it after the fact to make it invisible. It's one of those art-forms that are necessary to learn/perfect if one is going to do built-in things.

[Bob Cooper]

I built some shelves recently and they were about 18x40 if memory serves me right. I Attached the shelf from inside the torsion box into the studs. I did have places where there were no studs on the sides (on one side) and ended up using a high-quality anchor. I believe I can stand on the shelves, and in fact, I think I sat on them to verify they could hold my weight the covering his quarter inch Cypress.

[Cameron Wood]

A few years ago I did one of those. Didn't get any pics, but it ended up being stained VG fir plywood to match the other finishes, with solid nosing that hung down, mostly concealing ~1X2 cleats screwed to the walls on three sides. The front of the cleats were clipped to be less visible.
There was adequate framing except one front end, which got a beefy wall anchor and a bit of glue between the cleat and the sheetrock.

Another more recent job got kitchen/pantry shelves from 6/4 walnut- stopped dados sliding on to cleats fastened to wall and adjacent cabinet. That was a PIA partly because it was tucked in a corner & light strip.

More recently still, I installed cabinets in a recess, and attempted to make a stone top. The walls angled in a bit and there was some corner trim preventing the top from being slid in.
Because it was 3cm thick, cutting it and tipping into place was tricky, & it ended up with the fit to the walls a bit too loose. Fortunately, the client was OK with getting actual countertop fabricators to do it so I was able to punt.


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[Tom Bender]

So there are two challenges beyond your initial question.

1. How do you get the piece onto the space if the space is not perfectly square or tapered in your favor?

2. Suppose there is not a stud near the front on both sides? (I think you should assume someone will be injured if it fails when sat or stood upon)

My solution to the second would involve drywall work.

The first might be solved by making a sorta close plywood surface. Fill the gaps with drywall mud or other filler of your choice. Then apply veneer, which could be cut accurately and flexed as needed to get into place. Of course you will use plywood because expansion would make solid wood unworkable. Then of course you will need a front edge of solid wood. I'd make it from stock about 2 x 3 and make it the main support for the front edge with hidden fasteners into the walls. This big piece can then be generously shaped. The hidden corner could be scalloped organically for an intimate moment for the user, such as when on a rolling chair and pulling up to the desk.

Well...I seem to have wandered out of the box again.