Expert: Dan Griffin - 5/10/2008

Question
Hello, I just bought a new house. The upstairs has a good sun deck and the lower level has a nice patio. Now, I wanted to convert the patio to be a closed/built in one. The woods/logs holding up the deck is relatively new and in great condition.
The patio also have nice redish/orange bricks on the floor (like red bricks).

Please if anyone can advice, how much will it cost to turn the patio into a room and what might need to be done?
Please break it down by cost. eg for walls, roof so that the water from the deck does not fall in during rainy times etc.

THanks for all your help.

Answer
Water tight flat decks are problematic when designed from the beginning.  Converting an open wood deck to comply will require a fairly major rework.  Your point of beginning needs to be with the roof design, especially the flashing at the house side of the deck.  You will be adding a substantial load to the deck.

If you are thinking about truly closing in the patio with walls heading for additional interior space you will probably need to create a footing  under the perimeter of the patio.  The patio should have been installed with drainage pitch, probably about 1/4" per foot which will be objectionable in an interior space.  A screened in porch is a different project, but doesn't sound like where you are headed.  There is no way to generate costs with so much unknown.  You will probably need a well drawn plan to submit to your building department.  A good builder may be able to create a workable plan, but the deck may require the services of a structural engineer to satisfy permit requirements.