What are the IRA limits for dual income households?

An IRA is owned by one specific person.  So each spouse can have an IRA and the contribution limit is $5,500 per account.  

Whether or not those contributions are tax deductible depends on your income, filing status (married filing jointly or married filing separately), and whether you are eligible for a retirement plan at work.  See here for more. https://www.irs.gov/retirement-plans/ira-deduction-limits

"Can my spouse and I contribute $11,000 per year?"

Yes, as long as each spouse had at least as much earned compensation as the contribution if filing separately.   If filing jointly it does not matter which spouse earned the compensation as long as the total earned compensation is as much as the contributions.

Per IRS Pub 590A
<a rel="nofollow" target="_blank" href="https://www.irs.gov/publications/p590a/ch01.html#en_US_2016_publink1000230444">https://www.irs.gov/publications/p590a/ch01.html#en_US_2016_publink1000230444</a>

"Kay Bailey Hutchison Spousal IRA.   In the case of a married couple with unequal compensation who file a joint return, the deduction for contributions to the traditional IRA of the spouse with less compensation is limited to the lesser of:
   1) $5,500 ($6,500 if the spouse with the lower compensation is age 50 or older), or
   2) The total compensation includible in the gross income of both spouses for the year reduced by the following three amounts.
       1) The IRA deduction for the year of the spouse with the greater compensation.
       2) Any designated nondeductible contribution for the year made on behalf of the spouse with the greater compensation.
        3)Any contributions for the year to a Roth IRA on behalf of the spouse with the greater compensation.

  This limit is reduced by any contributions to a section 501(c)(18) plan on behalf of the spouse with the lesser compensation. "