How Can I Escape Special Charater....

here is the query


DECLARE @NENTITY varchar (100); SET @NENTITY = 'HouseDimension';


DECLARE @FLAGVAR nvarchar (10); SET @FLAGVAR = 'Y';



DECLARE @NFLAG NVARCHAR(50);



SET @NFLAG = (SELECT LEFT(@NENTITY, (SELECT CHARINDEX( 'DIM', @NENTITY) -1)) )+ 'LastUpdateFlag';



SET @SQL1 = 'SELECT * FROM ' + @NENTITY + ' WHERE ' + @NENTITY + '.' + @NFLAG + ' = ' + @FLAGVAR


SELECT @SQL1



OUTPUT: SELECT * FROM HouseDimension WHERE HouseDimension.HouseLastUpdateFlag = Y

where as I need an output with Y in single quotes ('Y')
because when I run this query its gives me an error invalid colunm name Y. I tried to use escape sequence but of no use..



Any suggestion please?