repainting decks and porches

Hi all! I am getting ready to put some refinishing touches on the front and back porch of my house, which mostly involves repainting. But I am wondering if there are anything I should be aware of, since this is outside painting (which I've never done).
My front porch is cement, and it looks like it's been painted over a couple of times. There was a big crack (over 1/4" wide) which I patched a few weeks ago with some type of concrete patch that comes in a little bucket. I figured that I will need to chip away as much of the old paint as possible, then scrub down the porch before I paint. But is there anything else I need to do? Do I need to scrub it down with TSP? Do I need to seal it with a primer or anything? What kind of paint should I use for concrete?
The back porch is made out of redwood. There is some mildewy spots on the deck where there sunlight doesn't always hit. For the most part, the deck just looks weathered, but it's still in pretty good shape. I might have to drive a few nails in where they've+ come a little loose, but other than that, no other real work. There is an old coat of paint on it now. Do I need to strip the paint off? Do I need to scrub it down? Do I need to seal the wood? What kind of paint should I use for redwood?
I had asked a couple of neighbors down the street who had repainted their front (cement) porch, but they said that all they did was go down to the Home Depot and just bought the cheapest cement paint available. Not that I don't believe them, but I just thought I should do a little research before I did the same. Any tips/advice/recommendations would be very much appreciated!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Washing everything with TSP is good. Power washing is better. Let dry and then get the cement paint for the front and the stain for the back. I just painted my cedar gate which was pretty weather beaten. I used stain from the big box store in a color that matches my home. The bear stain I used was acrylic latex. Clean up was with water. I used 1/2 gallon on 2 coats of a 4 foot gate. Weathered wood is thirsty some times. A friend of mine has to redo his redwood deck every year. Way to much sun here in Phoenix.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Cabot label says recoat vertical surfaces every 4 years and horizontal every 2 years.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@aol.com (Nospambob1) wrote in message

Cabot has given me good service on various projects over the years. TB
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.