Francina writes from Oxon Hill, Maryland: "I am renting a house where the owner added on a trailer to make an extra bedroom, the trailer is poorly insulated, and it is very cold even tho I put plastic at the window it still feels like I am outside when I am in the bedroom. Is there anything that can be done to keep the house warm? There is no crawl space so we can not get under the house."

Answer: I suggest contacting an insulation contractor to determine if insulation can be added to the walls of the bedroom addition. The contractor will know if it is possible to install Owens Corning Fiberglas™ "blowing wool" insulation products. You mention the lack of a crawl space but not whether there is any opportunity in the ceiling. Perhaps not, but since heat rises, insulating the top of a conditioned space is very important to overall thermal efficiency.