growing in a garage

I am setting my new room up rihgt now and decided to build a room in my garage instead of in the house for space issues. My main question is will i have to worry about spider mites and and other bugs more since i will be in a garage. Also i plan on building a cheap room out of plywood in the garage and am wondering what i should do in the winter time when there is snow. It gets pretty cold. I am going to be running 2 1000 watt hps lights that i iwll keep on at night time. But i am wondering what a good solution the my temp problem will be when my lights shut off i think my room will get too cold/

If your garage is heated you shouldnt have to worry about the cold, but that will attract bugs....why not grow inside your house?

a simple space heater. most will come with an internal temperature gage that will turn on the heater once it reaches below a set point. so if you set that gage to activate once it goes below say 0 degrees (32F) the heater will turn on for a couple of minutes untill its in a safe zone. im also pretty sure 2 hps lights will give your room alot of residual heat if kept air tight.
about the spider mites- if your garage is anything like mine, concrete floors, brick walls, no insulation, you may have a tough time keeping pests away. i have a small cab running in my garage but only deal with an annoying daddy long legs every once and a while. for the most part all bugs want is to be kept warm. ive noticed that none of the spiders ive had have go ne near the plants. also keeping your grow room really clean helps alot too.
hope that helps a little. just keep your room airtight, no light leaks and clean and you should have little to no problems.......o yeah and duct tape is a mans bestfriend

FYI look into this stuff called R-Matt, its a hard foam panels that is used for insulation you can find it at lowes in various thicknesses, but I built my walls aout of the stuff with tape no saws or heavy wood