Expert: Dan Griffin - 5/30/2011

Question
Hello,

We just bought a house on sloped land that is 3/4 th's complete. The entrance is at the street level and the living space opens up with two sets of beautiful French doors - problem? If you try to step out you fall a story as they never built the terrace designed with the house. The ground directly in back of the house for 4m is flat. We plan to build a deck that is 4m x 3m. I plan to use 6 by 6 posts for the support - 4 corners, plus an additional one on the long edged centered and then also tie into the house. I most likely use a Canadian pine that we will treat yearly. Also it appears the length of the posts above ground need to be at 3m. In saying this - Am I considering the right size post? Should I have more posts? How far apart should my joists be? We'd ideally like to make the frame as one piece or split it into three more manageable sections - any advice on this? Also we are considering not laying boards directly, but building easy to use and replace cubes of 1m x1m or 2m by 2m. We'd also like to do this ourselves if possible, but if it will pose too many safety concerns later we'll consider a professional

Answer
Ally, this is a fairly small deck and should be well within the abilities of careful work on a DIY basis.  It would be best to make the deck free standing, not depending on being pinned to the house.

I'm fairly sure you will need a permit to build this deck.  They may require frost depth footings, though this can be waved for an independent deck. They will require adequate railings that comply with the 4" ball rule.  You will probably want a stair case which will require hand rails, etc.  There is good information about designing and building decks here:
http://www.thisoldhouse.com/toh/article/0,,212625,00.html

http://landscaping.about.com/cs/hardscapefences1/a/deck_building_3.htm