You might want to reconsider putting carpeting down on the staircase. Wooden stairs are a nighmare to keep clean! I had to vaccum our hardwood stairs twice a day and we only had 1 dog at the time too. Also, the noise of kids and dogs running up and down the stairs was irritating. We finally ran a carpet up the middle of the stairs leaving the sides open but I still had to vaccum twice a day just to keep the dust balls under control.

Our new home has 3 interior full stairways and even though we have hardwood throughout the home, all stairways will be carpeted as well as all closets another nightmare to keep clean.

The plan was to put a runner up the middle. It is just my wife and I and you are right, the wood only stairs are very loud. We currently have wood stairs in our house with no runner which will be inflected on the next owners.

There is a more important issue. If you add hardwood treads over the existing treads then the top and bottom risers should each be off by an inch. You will probably have to replace the existing treads with 1/2" plywood and 1" hardwood treads assuming the stair was built correctly for carpet.

You are right. The stairs are 7.5" (outside code!) on the rise and 11 inches on run. Under the UBC I can get away with 8" rise. So I can use 1/2" thick treads. This is looking more and more like a carpet job.

Is there a way to have p;ywood down the main runner area and to the wall and then have nice hardwood trim on the banister trim side where you'll just get the effect of having a runner? I ask this because we had an older home where we had to carpet the newly refinished middle of the stairs because we woke the baby up with the noise. So now we are building a new staircase and wonder if we can skip building the whole thing in hard woods if only 20 percent of it is going to show.

Hardwood on only 20% is a can do. I was thinking of that also when I saw this product:

Here is a link that might be useful: Left Hand False End Cap Tread

Wow, thanks so much Robert. Once again I have a wonderful website to save to my favorities when I need it in the future. I appreciate those with more knowledge sharing with the rest of us.