Before a trip should I turn off the water of my house?

Put RV anti freeze in the "P" traps like you do in the RV. Does it stay there?I don't really know. If It does evaporate it would be slower. And it has a oily base. Should last long enough for your return.
Turn off the water valve to the house as you do to the RV when leaving for a length of time.I do. Witnessed to many flooded trailers with the water left on.

I always turn off the main valve in front yard of house and turn off the breaker to elec. water heater.

jplante4 wrote:
I had a ruptured diagram in the furnace (forced hot water) piping that caused the TP valve to intermittently open and dump furnace water into the basement. The makeup water valve kept supplying water to the furnace. I WAS HOME and caught it within an hour and still had 2 inches of water in the basement. I turn off the water when I go camping. I don't understand the down side of doing this.

If the water gets low it will fry your boiler. As I mentioned it is a good idea to have a drain in your boiler room.

Low-Water Conditions

The potential for severe and even catastrophic damage to a boiler as a result of low-water conditions is easy to imagine considering that furnace temperatures exceed 1,800°F, yet the strength of steel drops sharply at temperatures above 800°F. The only thing that allows a boiler to withstand these furnace temperatures is the presence of water in all tubes of the furnace at all times that a fire is present. Low-water conditions will literally melt steel boiler tubes with the result closely resembling a spent birthday candle, as shown above.

http://www.nationalboard.org/index.aspx?pageID=164&ID=238

I shut down gas and water, quake country.

There was a camp host I know that when he went back home to check his house he had those big black flies (sewer flies) had infested his house. The exterminator said the came up the drains after the traps had dried out. So he paid the bill and dumped a cup of vegetable oil down each drain. No more flies.w

I had a ruptured diagram in the furnace (forced hot water) piping that caused the TP valve to intermittently open and dump furnace water into the basement. The makeup water valve kept supplying water to the furnace. I WAS HOME and caught it within an hour and still had 2 inches of water in the basement. I turn off the water when I go camping. I don't understand the down side of doing this.

Having actually read the OP's post, which was NOT about turning the water off or not, I have never heard of any bugs coming up through the traps as long as they're kept full of water or something else. RV antifreeze works well, as does vegetable oil, to keep the liquid in the traps from evaporating for long periods. If there is any risk of freezing, I think RV antifreeze in the traps is the better choice.

We are snow birds and leave our house every winter for 4 or 5 months. We have a boiler and in-floor heat that both need the water connected. I have it set up so we can shut the water off to the house while leaving it on for the boiler. There is a drain in our furnace room in case a pipe should break. If you have a boiler be sure it won't do damage to it by turning the water off.

A neighbor checks our house every 2 weeks, turns the water on, waters the plants, flushes the toilets and runs water in the sinks. We have a thermometer with a remote sensor. The sensor is in our house the thermometer in his. He doesn't have to leave his house to check for the furnace going out.

Yes if your away for long periods the Roaches will come in through the toilet drain once the water has evaporated away. Flush the water out of the toilet bowel and put in RV antifreeze, it won't evaporate so quickly.

We've always turned ours off, and our trips are rarely longer than 2 weeks. The first time, I overlooked something that ended up costing me $400.

Our house is a 1700 square foot rambler, with the hot water heater in the west end of the garage and the kitchen at the east end of the house. The hot water pipe run is close to 90 feet. The builder included a hot water re-circulation system so we didn't run a gallon of water at the sink before it got hot.

I forgot to turn the pump off when we shut down the system. We were gone for 10 days and the pump was seized solid when we got back. If you have a re-circ system be sure to shut the pump off before turning off the water supply.