diff --git a/_grid/expand.m b/_grid/expand.m
new file mode 100644
index 00000000..8bd15eec
--- /dev/null
+++ b/_grid/expand.m
@@ -0,0 +1,36 @@
+	// now figure out which rows and columns really expand
+	hexpand = (BOOL *) uiAlloc(xcount * sizeof (BOOL), "BOOL[]");
+	vexpand = (BOOL *) uiAlloc(ycount * sizeof (BOOL), "BOOL[]");
+	// first, which don't span
+	for (gc in self->children) {
+		if (gc.hexpand && gc.xspan == 1)
+			hexpand[gc.left - xmin] = YES;
+		if (gc.vexpand && gc.yspan == 1)
+			vexpand[gc.top - ymin] = YES;
+	}
+	// second, which do span
+	// the way we handle this is simple: if none of the spanned rows/columns expand, make all rows/columns expand
+	for (gc in self->children) {
+		if (gc.hexpand && gc.xspan != 1) {
+			doit = YES;
+			for (x = gc.left; x < gc.left + gc.xspan; x++)
+				if (hexpand[x - xmin]) {
+					doit = NO;
+					break;
+				}
+			if (doit)
+				for (x = gc.left; x < gc.left + gc.xspan; x++)
+					hexpand[x - xmin] = YES;
+		}
+		if (gc.vexpand && gc.yspan != 1) {
+			doit = YES;
+			for (y = gc.top; y < gc.top + gc.yspan; y++)
+				if (vexpand[y - ymin]) {
+					doit = NO;
+					break;
+				}
+			if (doit)
+				for (y = gc.top; y < gc.top + gc.yspan; y++)
+					vexpand[y - ymin] = YES;
+		}
+	}