There are quite a few people who own more than one house, many of whom find that they need to refinance one. In general this is not an issue but you do have to realize that there are some different rules that apply to mortgages on houses that are not your primary residence. This will affect when it makes sense to refinance more than it does your actual ability to do it.
Normally there is no issue with refinancing if you have more than one house although there are a couple of things that you will have to keep in mind. The biggest issue that you are going to face is that you will have one of those houses listed as your primary residence. It is much easier to refinance a house that is your primary residence than it is to refinance a house that is not. The reason for this is that the bank assumes that you will be more likely to make the payments on a house you are actually living in. The government's rules also make it easier to refinance the house that you are living in.
If you want to refinance your primary residence you will find that the rules are the same as they are for any other refinance. However if you are trying to refinance a house that is not your primary residence things will be much more difficult. The main difference is the amount of equity that you will have to have in your house. In most cases a mortgage on a house that is not your primary residence will be limited to eighty percent the value of the house. Therefore refinancing for the purpose of taking equity out of the house makes far less sense.
One option that some people try is to make the house that they want to refinance their primary residence. In general this is something that you are going to want to avoid since it will create all kinds of problems for you with mortgage on the house that was formerly your primary residence. This is especially true if you have a mortgage on that house that is for more than eighty percent of the value of the house. It is generally best to avoid this whole issue.
There are times when it might make sense to refinance a mortgage on a house that is not your primary residence, for example if you can get a lower interest rate. This should not be a problem since you will have had to meet the equity requirements when you took the first mortgage. Really the only restriction that you are going to have on you when it comes to refinancing a second house is that you will find that there is little value to trying to turn the equity into cash.