Expert: Dave Johnson - 9/16/2008

Question
We are thinking about building a sunroom onto our home.  If we use footings with a crawl space underneath, we would lose the only basement window in our downstairs rec room.  However, if we build it as you would build a deck, we could keep the window.  Our big concerns are: would this method support the weight of a 16X20 room?  Would the room be too cold?  We live in Iowa.  We have seen a lot of new homes with their sunrooms being built this way, but aren't sure if this is a good idea or not.  Thanks for any information you can give us!

Answer
Hi Stacy,
Yes, if it is built correctly, it will support the addition.
You could use pre-cast piers and bury them 4' in the ground, or pour your own with tubes.
The room won't be cold if you insulate well. Use some 2"x2" ledgers on either side of the joists to use as stops... then cut 2" foam to fit and let it down to the stops. (here i would add as much as i could on top) then cover with the sub-floor.
If this isn't clear, please mail me again with specific questions...
Best of luck,

Dave