Building steps for an attached deck

Hello all,
I'm trying to finish up my attached deck. The deck surface is 3 feet above the ground where I intend to place the steps. My question is, given that the end of the deck furthest from the wall is supported by three columns that sit on 4-1/2' concrete piers, do I also need to dig (and pour) 4-1/2' deep holes for each of the three stringers to land on? Or can I get away with a 6" thick slab? If a slab, what would be the minimum width and length? Do I have to bolt the bottom og the stringer to the cement or is it enough to anchor the tops of the stringers to the deck rim joist? Thanks for any suggestions!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I don't think you need to put a footing for each stringer. Generally , it would be ideal on a slab, but I've seen people use those brick and patio pavers in the dirt as a footing. As far as anchoring, I used a joist hanger for each stringer at the top. On the bottom, you should put some kind of anchoring. If you are using a slab, just anchor each stringer to the slab. Or if you are putting posts at the bottom for the railing, anchor the stringer to the posts, and the posts to the ground. But in general, the top anchoring is most important.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Thanks for your reply Mikepier, I wonder if you could answer a couple more questions...
How far should the slab extend the stringers? (What are the dimensions of the slab knowing that the width of the steps is 6 feet? And would 4 stringers suffice?) If the deck is on frost piers, won't the slab move with the ground? (I'm just trying to understand why the steps wouldn't be pulled from the deck's rim joist if they are anchored at both the slab and the deck.)
Thanks again for your help!
Dale
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
4 stringers should be enough for a 6 foot wide stairs. If you are using 2X6 as treads, then that means they will span appox. 20" between each stringer. The max you can span with 2X6 is I believe 24". And make sure you use 2X12's for stringers, not 2X 10's like some people I've seen. I'm not sure what frost piers are. Are those the piers that look like elephant feet for a floating deck? Also what is at the ground level of the deck, grass?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

A frost pier is just another name for a cement column that extends past the frost line. They keep the deck from heaving with the season changes. Mine have a 19" diameter (overkill) and are 5' in length (4-1/2' deep with 6" extending out of the ground). The deck is attached to the house and supported on the other end by 6x6 posts anchored to three of these piers. And yes, the ground level is grass.
Thanks, Dale
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

2 x 6 for treads? I hope there will be two of them. The actual dimension of 5 1/2" is not to code.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
That's what I meant to say, sorry. 2 2X6"s to give you an 11' tread.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
As a supplement to Mikepier: Check the beam to which the steps are attached for strength. Steps dropping three feet should be anchored at the bottom. I'd consider shims or spacers to let water drain from the bottom end grain. International Residential Code requires a "Guard" 36 inches high if deck or stair is more than 30 inches above grade.
TB
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Thanks for your reply, TB. If you have anything to add to the questions posed to Mikepier, I would be greatful!
Dale
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.