USE tempdb
GO

IF EXISTS (SELECT * FROM sys.tables WHERE name = 'SizeCheck') DROP TABLE SizeCheck
GO

IF EXISTS (SELECT * FROM sys.tables WHERE name = 'SizeCheck2') DROP TABLE SizeCheck2
GO

CREATE TABLE SizeCheck (
  ID INT NOT NULL IDENTITY(1,1) PRIMARY KEY, 
  Value VARCHAR(8000)
)

INSERT SizeCheck (Value) 
SELECT SPACE(8000) 
FROM sys.all_objects

UPDATE SizeCheck SET Value = SPACE(1)

SELECT * INTO SizeCheck2 FROM SizeCheck

EXEC sp_spaceused SizeCheck
EXEC sp_spaceused SizeCheck2

/*
name            rows            reserved        data            index size unused
SizeCheck	1987       	16008 KB	15896 KB	72 KB	40 KB
SizeCheck2	1987       	80 KB	        48 KB	        8 KB	24 KB
*/