Yes, you can get a backhoe and dig a trench around your house for relatively cheap but, it really is a waste of time. Parging the walls first pretty much means coating the walls to make sure moisture does not get behind the insulation that you are going to put up. I suggest using a modern basement epoxy of some sort and I recommend rigid insulation after you have done that. Rigid is easier to work with and you can make the whole project into an adhesive affair where you adhere the furring strips to the epoxied walls and then you adhere the foam board (or whatever) to the furring strips. Boom, you are done unless you need to paint them for someone else in the house that hates the color of the “naked” board. You know who I mean. Like the article says as far as the vapor barrier placement you have to call your local building code people cause I got no idea,
Exterior wall insulation inside the walls
Insulating outside your exterior walls is often too expensive or impractical in existing homes. You can insulate the inside of your basement walls but you may exacerbate the problems associated with moisture if you don’t do the job correctly.
Parging: If moisture is seeping into your walls, parge the masonry walls to seal any cracks and strengthen any weak or porous masonry. This will help prevent water from seeping in from outside.
Vapor barrier: Vapor barrier should be outside the insulation if you are in a hot climate and only cool your home; it should be on the inside if you are in a cold climate and are mainly heating your home. Consult your local city building permits department to find out what are the suggested or mandated insulation and vapor barrier configurations for energy efficient basements in your area.
Framing: If possible, leave a gap between your framing and the exterior walls, to prevent moisture from the masonry from causing wood rot in your framing. Use small spacers behind 2×3 studs, rather than 2×4 studs against the outside wall, and you’ll still have room to install the standard insulation for 2×4, 16-inch-stud construction.
Insulation: If there is any likelihood of moisture getting into your basement, use a rigid foam insulation rather than batt or other fiber-based insulation. Moisture seeping through exterior walls will dampen the insulation and reduce its R value significantly within a few years, so you’ll start with an energy efficient basement and in a few years be losing as much heat to outside as before the renovation. Moisture will not have much effect on the R value of foam insulation. Buy the highest R value insulation you can – you can get an R value of 6 per inch in some insulating foam sheets. If you want both insulation and waterproofing, you could consider having Icynene insulation applied to exterior walls after framing but before drywall is installed.
Other places you should insulate
A couple of other important things to consider about basement insulation:
- In an older house, where a shower stall is already installed against an outside wall, check the insulation level behind the shower. A prior owner or contractor may have installed the shower without adequate insulation. If you are remodelling or can access the wall space behind it, inject foam insulation or otherwise upgrade the insulation. You’ll have more comfortable showers and you’ll cut down on overall heat loss.
- Insulate the perimeter of your basement ceiling (an area called the ‘rim joists’), from the outside walls to about 16″ to 24″ from the outside walls, to prevent moisture from creeping in between the upstairs
In this case, go there and read a bunch. More tomorrow.