Bloodlines counts towards ECL by RAW!

[HouseRules]

By RAW:

The Object of X Volume fits into Y Space for Z Size Category.

Size	Volume	Space
Fine	0.5-foot cube	0.5-foot square
Diminutive	1-foot cube	1-foot square
Tiny	2-foot cube	2.5-foot square
Small	4-foot cube	5-foot square
Medium	8-foot cube	5-foot square
Large	16-foot cube	10-foot square
Huge	32-foot cube	15-foot square
Gargantuan	64-foot cube	20-foot square
Colossal	128-foot cube	30-foot square

Yes, you could fit those larger objects into a smaller space than them.

Mechanical Units of Measures
Thickness of Materials: multiples of 1 inch.
Height: 1 foot.
Distance: 5 foot.