4×8 vs 5×5: buy the size that costs less, not the one that sounds cheaper.
Baltic birch 5×5 sheets nest some cabinet work onto one square. Construction 4×8 is
cheaper per sheet and takes long parts a 60-inch square cannot. Paste the parts,
type what your yard charges, and see which size you should actually load.
Four 28 × 28 doors, 1/8-inch kerf, no edge trim. That is a real cabinet door blank,
not a toy list.
5×5 at $90: one sheet, $90. High utilization, one trip.
4×8 at $42: two sheets, $84. Six dollars less cash, more offcut.
4×4 at $22: four sheets, $88. Easy to carry, not the cheap buy.
Flip the 5×5 to $55 and the 4×8 to $62 and the ranking reverses: one Baltic sheet
is $69 cheaper than two 4×8s. The answer is the yard ticket, not the folklore.
Rank this list on your prices
Change a price or the parts to rerank.
When 4×8 is the only size that works
A 72-inch bookcase side will not fit a 5×5 even rotated. The 5×5 can be cheaper
per sheet and still be the wrong buy because two pieces never leave the oversize
list. Long casework, stair treads, and tall doors are 4×8 (or 5×10) jobs.
Common questions
Is 5×5 Baltic birch cheaper than 4×8 for cabinet doors?
Only if the extra you pay per sheet is less than the sheets you avoid. Four 28-inch doors fit on one 5×5 and need two 4×8s. At $90 versus $42, the two 4×8 sheets still cost $6 less. At $55 versus $62, the single 5×5 wins by $69.
When does a 4×8 beat a 5×5 even if I need more sheets?
When the 4×8 is cheap enough that two (or three) of them still cost less than one Baltic sheet, or when a long part will not fit the 60-inch square at all — a 72-inch bookcase side is the usual case.
Should I buy half-sheets instead?
Half-sheets (4×4) are easy to carry and sometimes cheaper per sheet, but you often buy more of them and pay for more edge trim and kerf. Rank them on the same list before you assume they save money.