Replies

1. 
   DanH | Apr 10, 2016 10:05am | #1

   Cement or concrete?  There's a difference.

   And of course it matters what the posts are made of and how deeply they're set into the ground (if at all).

1. 
   norseman68 | Apr 10, 2016 12:23pm | #4

   yes, there is a difference, sorry for the confusion...the posts are going to be pressure treated 4x4's about 4 feet in the ground to get pass frost line...in concrete

2. 
   deadnuts | Apr 10, 2016 10:49am | #2

   If you use CCA treated lumber rated for ground contact(.60 or greater is recommended), then you can probably expect at least 20-30 years out of your posts. Poorly drained foundations can reduce service life. We usually coat the sections of posts embedded in concrete with asphalt tar to reduce wood fibers coming into direct contact with caustic concrete.

1. 
   norseman68 | Apr 10, 2016 12:25pm | #5

   thanks...the tar idea is a great idea...as my yard is quit moist at the best of times due to the lack of good drainage...

2. 
   DoRight | May 13, 2016 06:58pm | #8

   I find tar does not always adhear to the wood.  But I am often using round cedar posts and perhaps they are still a bit green (not sure)

3. 
   renosteinke | Apr 10, 2016 11:48am | #3

   It's a SHED

   Some time ago, this site posted a very nice video series on building a shed - and there was no slab, nor were posts set in the ground. Instead, the shed sat atop a nice bed of gravel.

   There's your key; good drainage.

   When I built my shed, I simply raised it off the ground with pier blocks. No part touched the ground directly.

   How you build depends on your intended use, and the size of the shed.

   At 320 sq. ft, your shed is large enough to trigger permit requirements in most places. I'd see if your town has specific requirements.

   As for the choices you presented, I have a bias in favor of the brackets. After all, the brackets can be easily adjusted for level once the concrete had set. I don't like seeing any lumber, even treated lumber, closer than 6" to the ground; why tempt termites?

4. 
   Mike_Mahan | Apr 10, 2016 01:07pm | #6

   Footings

   If you set posts in concrete are not bearing on anything. The gravity loads of the building are supported only by the friction between the wood posts and the surrounding concrete. Your structure would stand a good chance of settling over time. Pole structures almost always have the poles set on reinforced concrete footings even if they have concrete poured around them. I can see no reason to set the posts in concrete and many reasons against doing it, rot included.

1. 
   coonass | Apr 12, 2016 10:14pm | #7

   Mike,

   That's why you hang the post from the surface and pour 8"s of 'crete below them in a monolithic pour. Down here in our clay soil that doesn't perc setting post in 'crete is better than gravel. I have some that are 36 years old and still rot free.

   KK