Expert: Jamie Yocono - 10/21/2007

Question
I have a beautiful mahogony 4 poster bed in a queen size...I would like to refit it to be a king size...is that possible


Answer
Hi Robyn,

Unfortunately, unless you posses a good deal of woodworking skill, changing a queen sized 4 poster bed into a king size is somewhat difficult. I will try to explain, and then if you do, indeed, have the tools and skills necessary, you could probably attempt this changeover.

The big thing is that you're going to need to disassemble the head board and footboard, to lengthen them. Taking that joint apart is often difficult, as it's usually constructed with a mortise/tenon joint. That joint is commonly pinned with doweled, in order to make it stronger. Unfortunately, pinning it makes it quite difficult to take apart.

So the first step is to look at how the headboard and footboard connect into the 4 posts.  

Next, you're going to need to make those two cross pieces, only longer, to accommodate the king mattress. I believe a queen bed is traditionally 60" x 80". A  king is usually 76" x 80". (in some cases, either of these mattresses can be 84" long, too, but that's not important; the width is what you're going to change.) So that means you're going to need to make the new piece 16" longer than the existing piece. Now- if the one you remove is, for example, 59 1/2" long, then the new piece you'll be making is going to be 75 1/2" long. You want to make the new piece exactly 16" longer, since the difference is 16". So it's a half inch undersized, or one inch oversized, adjust your length dimension appropriately.

You'll want to reassemble the new pieces exactly the way you removed them. So if they were doweled, you'll need to drill some holes for dowels. Or if it was a mortise/tenon as I mentioned above, you'll need to cut new tenons. If this is the case, make sure you don't cut the headboard and footboard too short. You'll want your shoulder to shoulder measurement the same as your old pieces, only 16" longer.

As you might have guessed after reading this, lengthening a headboard and footboard is fairly labor intensive. I recently made two bed side rails for a client who bought a bed, but discovered his mattress was too long. But changing the length of the side rails is MUCH easier than changing the width of a bed. It's CRUCIAL that you have tools and the skills to cut new joinery. If you don't it's quite possible that you could ruin the bed.

Good luck, write back if you have more questions, or if you need more information.

Jamie Yocono
Wood It Is! Custom Cabinetry
Las Vegas, NV
www.wooditis.com