A triangle shaped loft bed has an elevated platform frame that holds a mattress, and this frame is supported by (4) corner posts with an attached ladder to access the bed. The area under the platform is open and may be used for any number of reasons.
The height of the platform will be approximately six feet, the length will be approximately 84" (or 7') and the width will be approximately 48". These are approximated dimensions based on a standard twin mattress. The size of the platform can be constructed to accommodate most any size mattress.
The materials will be 1-1/2" thick smooth spruce or pine (referred to as stock) in various widths, 1/2" sanded plywood, 1/4" wood dowels and various hex head lag bolts, nuts and washers as described herein.
Begin by assembling the bed frame. Using stock that is 12" wide cut (2) pieces to the width of the mattress plus 2". These will be the end pieces. Cut (2) similar pieces of stock for the sides using the length of the mattress plus 2" overall and add 3" to account for the combined width of the end pieces.
Cross cut the ends of these pieces on a 45 degree miter and pre-drill (3) 1/8" pilot holes on each end of each piece. Be sure to offset the alignment these holes. Attach the frame together using glue and 2" wood screws, countersink each screw to 1/4' depth and fill the countersinks with wood dowels, sanded to flush.
Next, using glue and 1-1/2" wood screws attach a 1-1/2" x 1-1/2" ledger around the inside of the frame to support the mattress platform. The line of these ledger pieces should be no less than 6" from the top of the frame.
For the legs begin by cutting (4) pieces of stock 8" wide to 6' length plus the width of the frame, or approximately 12" over 6'. Cut (4) additional pieces to 6'length plus the distance from the underside of the frame to the underside of the ledgers. Cut (3) spacers from the same stock and lay these out on the long pieces, evenly spaced with the top and bottom spacers even with the ends of the short piece.
This will form an interlock at each of the corners. Attach the legs to the frame using 1/4" hex head lags 2-1/2" long. Countersink the lags 1/4". Use (2) lags on the outside of the frame and (10 on the inside at each corner.
Stand the frame and cut 1/2" plywood for the mattress platform. Install the plywood with glue and 1" wood screws at every 6" along the ledger.
For mattresses over 38" in width install additional ledger pieces across the span of the platform every 36" apart.
For the ladder cut (2) pieces of 12' wide stock to 8' length. If a straight ladder is not desired cross cut the ends at an angle of 17 degrees to allow the ladder to perch at a slight angle to the floor for convenience. These pieces will be the stringers.
For the ladder treads or rungs cut (6) pieces of 12" wide stock for ladder rungs. These can be between 12" and 18" long depending on the desired width of the ladder. Align these pieces with the edges of the stringers either on the square or to match the floor angle of the ladder.
Attach by drilling 1/8" pilot holes through the outside of the stringer and into the center of the rungs. Use glue and 1/4" x 5" lags bolts, countersunk to 1/4". Attach the ladder to the bed frame at the desired location using short pieces of ledger stock that is glued and screw attached to the frame. Affix the ladder to these ledger blocks.
The bed frame can be painted or stained to the desired finish.