Could Sub domains damage our SEO?

[NigelJ]

Hi there,

We're currently looking into integrating a new internal search function to our site which will involve housing the search results on a sub domain of our site.

We have no intention of these search result pages becoming landing pages for organic traffic but would the inclusion of a sub domain affect the optimization of the main domain? i.e. could it effect our authority?

Nige

[JamesNorquay]

Sub domains will not affect the PR and the Domain Authority as Google treats them as a separate domain.

The common issue made with sub domains is that people place the same content on the sub domain as they have on the main site and think it is ok. Well it is not and this causes duplicate content issues. So my question is when you have this search function for you site will it house the data which is already found on your website and also on the sub domain it could cause some concern with multiple content showing.

But really another problem with sub domains is that people start linking to them and then you have no link juice flowing to other parts of the website.

[RyanKent]

Using a subdomain can have affects on your SEO. Google has stated there are over 200 factors considered in determining a page's ranking in search results, but SEs don't search algorithms are a closely guarded secret so it's not possible to know what all the factors are, and what weight each factor is given.

When a user leaves your domain then numerous stats can be affected such as bounce rate, time on site, etc. These results could impact SEO.

With that said, the idea you are suggesting is something I have not seen before so I am always interested to see the results. Sometimes they are surprising.

[NigelJ]

The impact of the users interaction with the search results will be interesting to see.

I'm certainly interested to see how the sub domain search plays out. It will be interesting to see how the search result pages perform in the  serps.

If we go ahead i'll keep the mozers up to date with the effect.