Expert: Bruce E. Johnson - 6/17/2011

Question
Hi,

I am going to build a shed in the back yard and am looking for some help.  I am overall good with wood and eager to try this project.  Our yard is fairly level except where the shed will be built.  This area the land has a slight slope.  The entrance to the shed will be at the level part of the land and as you walk into the shed to the back, is where the land slopes downhill.

I am looking to build one either 8x8 depending on which side provides less wastage when cutting.  I would like to have it built so when at the beginning of the yard, I can walk towards the shed, go in, and it would be level.  Ill be using it for things that will be wheeled in.

From my understanding I would use 6x6 perimeter frame which would sit on the deck level block.  ( the blocks that you put a 4x4 or 6x6 in and you cut the wood at whatever height that makes it level all the way around).  Inside, I would screw 2x6x8 for floor support to the frame then placing 8x4 plywood for the floor.

Would this provide adequate support or do I need anything under the 2x6x8??  Also, what is the lifespan difference between pressure treated and non-pressure treated wood.  

Any help is greatly appreciated as I am alone doing this and don't know a whole heck of alot about it.

Answer
Hi Rookie, Okay from what I gather you are building a beam type of support upon which you will have 2x6 joists making up the floor system with plywood on top?  The 2x6's are spaced no more than 16" apart? And your plywood should be 5/8" minimum 3/4" preferred.  Lifespan between treated and untreated wood is big.  Untreated wood in a shed environment will attract and provide nourishment for any number of creatures including, carpenter ants, termites, carpenter bees, you name it they eat it. I'd do everything pressure treated to be on the safe side, the beams the joists, and the plywood.   I would put a layer of black visqueen 4mils thick 6 mils preferred directly on the ground after your support blocks are in place.  This keeps vegetation from growing underneath and helps keep ground moisture controlled. I hope this information helps please feel free to write again regarding this or other matters, sincerely bruce e johnson..bejohnsonconsulting.com