Expert: Dan Griffin - 3/16/2009

Question
My husband and I have a screened in porch between the garage and inner house.  We would like to turn it into a den or hang-out room for our teenagers.  The floor is concrete slab and we are not sure how to make this work as far as new flooring/heating/cooling would go.  Can you help?

Answer
Amanda, here are a few thoughts and considerations.

YOu never tell where you are.

If this will be done to code, it will require a building permit.  The first issue will be whether there is a footing under the slab.  It was probably a patio at one point, I doubt it would have had a footing, it probably did not have any type of vapor barrier, the concrete was intended to be exterior concrete so it has pitch to be able to shed water.

The footing issues can be dealt with, but may require cutting out portions of the concrete to be able dig and install them.  The lack of a vapor barrier might stop the project cold, it will certainly restrict flooring choices depending on your ground water circumstances.

It may be possible to install a suspended wood framed floor to raise the level up to the house floor.  This might not work out with garage height and existing doors.  You could leave the exposed concrete and acid stain the floor.  It would also be a candidate for ceramic flooring.

I have no idea what your existing HVAC is now, but it probably was not sized to absord your new space.  If it was a FAG system with an upflow furnace, it should be possible to extend some duct work to the space, return air will need to be addressed.  The most simple approach may be to use a "motel" unit - through the wall heat and cool usually below the window of a typical motel room.  Maximize the wall and ceiling insulation to minimize the heat/cool load.

I know this has left you with a lot of questions, but I would need a lot more information to go on.  Are you planning to do the work or hire it out?  Sit down with a local builder who can see the issues and discuss the possibilites.