Using multiple sensors with same address

I want to use some Sparkfun temp/humidity sensors HIH6130 to record what's going on inside and outside a building. It looks like they come with the default address of 0x27 (I2C). How would I go about talking to them? Should I do the simple thing of a relay isolation and select each one via relay? Would it bother them (or the clock driver) to not isolate the clock lines, or just go ahead and use a DP relay?

It seems as if you can rewrite the I2C address, in particular you need to write to EEPROM register 0x1C, bits 6:0. See the command mode instructions for details. The information is a bit scattered through the document, but Figure 5, step 10 shows how to set the I2C address to 0x53 together with changing some other settings.

Thanks. hadn't looked at that data sheet yet.

Another question. I haven't worked with I2C yet. In the command diagrams, there is an ACK bit? shown in the string. Is one byte sent at a time with an ACK coming from the slave? I need to look at some basic protocol sheets I guess.