Use a long-sleeved shirt and safety glasses when you work with any kind of insulation. Measure the outhouse’s interior walls from the footer boards up to the header boards. A type of starter lining called an airflow barrier is basically just a piece of fabricated plastic. Use plastic insulation as an inexpensive and easy way to provide insulation in your outbuilding. The air barrier material helps keep air outside where it belongs and keeps the internal temperatures steady. To install you simply need to wrap sheets of the air barrier around the interior walls of the outbuilding and tack in place. If your backyard outhouse diagrams ask for more insulation and padding the airflow barrier works well as a foundation. A great layering insulation that is often times used is well-known fiberglass. Cover the fiberglass with more wall material once it has been laid against the wall. Hide your fiberglass insulation with drywall and screws if you want to finish the interior walls with paint....