No-sparge brewing skips the sparge step entirely — all the water a batch needs goes into the mash itself as one large strike-water addition, and the wort is simply drained off without any further rinsing of the grain bed afterward.
The simplest process, and the honest cost of that simplicity
This is about as straightforward as all-grain brewing gets: one water addition, one mash, one drain, no timing two rates against each other and no calculating a separate sparge volume. The trade-off is real and predictable — leaving the grain bed unrinsed means real sugar stays behind in the spent grain, so no-sparge brewing typically runs several percentage points lower in extract efficiency than either batch or fly sparging on an identical grain bill.
When accepting that efficiency loss makes sense
Brewers using this method usually compensate by simply adding more grain to hit the same target gravity, which is a perfectly workable trade for a homebrewer prioritizing simplicity and speed over ingredient cost — a genuinely reasonable choice for a smaller batch or a brewer who values a shorter, lower-effort brew day more than squeezing maximum yield from every pound of grain purchased. Brewhouse efficiency figures for this method should be tracked separately from a sparged setup's own numbers, since the two aren't directly comparable.