Please excuse me if this is the incorrect forum to post this question.

We would like to have an addition built on our house. I know about HELOC's
and Home equity loans. I was recently talking to an acquaintance who
mentioned a "blended mortgage". Here's how he described it. Talk to your
mortgage company. See if they will do a construction loan for the
addition. Pay the going rate for the construction loan. When it comes time
to close the construction loan and make it permanent, have them roll it into
a 30 year mortgage and then "blend" my previous mortgage (at 5.75%) with the
current going rate. I'm not sure if I can do this with another company
other than who holds my current mortgage and get some of the benefit of my
current mortgage rate.

Anyone know if this can be done? I will certainly call my current mortgage
holder (Chase), but want to make sure I have the terminology right and can
explain it correctly.

TIA,

B