If you are gluing veneer to a wood surface, you can use an old clothes iron to help. First use a sponge to wet the face of the veneer so that it won't curl. Next, apply a thin film of glue to both the surface and the underside of the veneer. Then, when the veneer is dry to the touch, use the clothes iron at a high setting to secure the veneer in place.
It’s possible to retrofit insulation into an existing home, even without the access provided by remodeling. The choices, however, are much more limited. There are some retrofit insulation products that are designed for minimal disruption to finished wall or ceiling surfaces. Significant gains in R-value, however, may mean hiring a professional to assess your needs and devise an energy savings plan. Small or large, insulation projects can yield substantial gains in R-value and in comfort.