Help with loft bed construction - DIY Chatroom

burntdawn · 09-11-2008, 08:04 PM

I am building a loft frame for a queen size bed. Two sides of the loft will be against walls and I plan to use 4x4 beams as supports where the frame will not be screwed into the walls. So basically I will have a frame of 60" x 80" built out of 2x6's, 2 sides of which will get screwed into the walls, with 4x4's holding up the other side. To frame out the base, I will also be using 2x6's every 16 inches. I will use plywood on top for my mattress to sit on.

My question is what is the strongest way to attach the 2x6's to the frame? I can pre-drill and screw the nails directly into the edge of the 2x6 or I can use those metal brackets that get screwed in to the frame and the 2x6's sit in?

The guy at home depot today told me I should nail the 2x6's into the wood rather than do either of those, but I much rather use screws if possible. I always though pre-drilling and using screws was better than nailing, but he advised me otherwise. I just don't want this thing to fall down or wobble. Any advice?

Thanks!

**thekctermite** · 09-11-2008, 08:45 PM

I built dozens of these in my old fraternity days back in college. We made them pretty elaborate, with rope ladders steps, hunting tree stand screw-in steps on the posts, etc. I slept in one for 5 years and never got used to bumping my head on the ceiling in the middle of the night.

My suggestion would be to use joist hangers. That will make it very strong. I wouldn't ever recommend screws in an actual structure, but for your purposes they'll work just great. Use 1-1/4" deck screws or similar.

For the corner connections use these or something similar on the interior side of the frame.

For the joists, use these in a 2x6 size.

If you don't care for the metallic color you can spray paint them before you put them up.

Be sure that you secure the "ledger" of the bedframe to the wall studs and not just the sheetrock.

burntdawn · 09-16-2008, 11:51 PM

Thank you so much for your advice. I took it and purchased the joist hangers and angle brackets. Now I am getting started on the project and it is humbling me.

My question now is the best way to attach the 2x6 frame to the 4x4s. My plan was to use bolts but I am not sure how many I need and exactly what the placement to be. I want to use enough that it is strong, but not too many that I start losing structural integrity in the post. My original thought was to use 2 on each side but once I started to lay it all out I started to think that is too many holes in the 4x4. I decided to do one bolt in the middle on the shorter side and 2 bolts (top and bottom) on the longer side for strength. I didn't realize it would be difficult drilling a straight hole into the 4x4 but it proved to be. I am getting better, but before I continue, I thought I should inquire about my bolting method. I would also be interested in hearing about better techniques.

Also, how long of a wood screw should I use to attach the 2x6 to the wall stud?

Thanks in advance for taking the time to advise a novice.

**thekctermite** · 09-17-2008, 12:56 AM

I'd opt for about four 3/8" bolts through the 4x4. Just put them in a square pattern. It'll hold. I'd suggest clamping the 4x4 to the 2x6, and drill through both at the same time. You'll need a fairly long drill bit. Or, you can drill the holes in the 2x6 and use a nail to mark the hole locations on the 4x4.

For attaching the loft's "rim joist" to the wall, you just need to be sure you're hitting studs. Honestly, 3-1/2" deck screws would work just fine if you put two or three in each stud. You could also go with 1/4 x 3-1/2" lag screws. You'd need to pre-drill holes for lags, but they'd be super-sturdy. I'd use one per stud.

If I were doing it, I'd forget the bolts at the post and do this...
Use a circular saw set to 1-1/2" deep to notch out the post to allow the 2x6's to rest ON it, not next to it. Very easy to do, it makes a cleaner look when you're done, and nothing's stronger.

Here's a little sketch to illustrate what I'm talking about...

**thekctermite** · 09-17-2008, 01:07 AM

Here's an easy way to make the notches in the post.

burntdawn · 09-19-2008, 12:55 PM

Thank you very much for the detailed drawings! I was originally thinking of the notch idea, but was intimidated by the cutting. You are inspiring me to rethink that option. Now that I screwed up a 4x4 and have to buy another one, I think I will use it to practice. If I take this route. How many screws would you suggest to join the 2x6's to the 4x4? Should I also screw the 2x6's to each other?

Thanks again for all your help. I will post the result.

jeepnfl · 01-03-2009, 01:27 AM

Let me dust off this post and ask a question. I'm also building a loft which will be attached to one wall with two 4x4's for the front support. I'm planning a mortise and tenon joint for the 2x6's into the 4x4's and a half lap joint for the 2x6-to-rim joist joint. The rim joist will be secured to the wall studs with 3.5" by 5/8 lags and washers. These same lags will be used to secure the 2x6 to 4x4 mortise and tenons.

I was then planning on just running a 2x2 around the inside with 6 1x3's supporting the mattress. My other thought is to use 2x4 "joist" with a sheet of plywood. I'd rather use the 1x3's seeing as I have already purchased those.

Please let me know what your thoughts are on the M&T 2x6 to 4x4 and the mattress support. I'll be assembeling this in the morning so if you know of a better way to complete any of this I'd love to know!!

Thanks,
Randy

**thekctermite** · 01-03-2009, 05:14 PM

Sorry if it is too late for this question to be answered, as you were going to do this project this morning.

Personally, I would not waste time with a mortise and tenon joint for a loft bed framed from dimension lumber. If you were making it out of cherry or wanted it to look like fine furniture a M&T joint would be great. Half lap joints (or notched) or simple framing connectors will be more than adequate.

Depending on the width of the bed, you may wish you had used 2x3's or 2x4's for slats. If it is a twin size bed, 1x3's will be fine.

jeepnfl · 01-08-2009, 12:15 AM

Thanks for the post. I went ahead and used the mortise and tenon and I agree it's probably overkill but I feel good about it. Also I've decided on using 2x4 joists with a sheet of half inch plywood for the bed base. Here's some pics of the current progress; I think it's turning out great! A little more detail work to complete and she'll hopefully this weekend.

**thekctermite** · 01-08-2009, 12:57 AM

Very nice. The steps/shelves are very creative and the M&T joinery is something to be proud of. Thanks for posting pics. Post some completed ones when it is all done!

sdm2009 · 10-14-2009, 05:14 PM

Does it matter what mattress to use for this project?

Willie T · 10-14-2009, 07:14 PM

I like it! Really sharp. You going to skirt this side of the steps too? Kids get careless, and the open area could become a leg breaker.