Installing Reflective Bubble Insulation
For between joists installation, the most common method is to staple the insulation between the joists using a standard construction stapler and staples. Properly installed, the insulation is very effective in preventing heat loss from convection and radiation methods of heat transfer.
If the joists will not be covered with drywall, such as in a case of a crawl space or unfinished basement, the bubble insulation can be stapled directly to the underside of the joists.
For finished basements, the insulation would need to be fully inside the joist bay so as to allow for drywall installation. In this scenario, the edges of the insulation are stapled to the sides of the joists so that the insulation does not touch the PEX tubing or the heat transfer plates (if used).
Taping the seams is highly recommended to prevent moisture penetration and buildup.
For concrete slabs, the insulation is unrolled on top of the compacted base (such as gravel) or positioned on top of existing slab, then cut to size and the seams are taped with 3" or 4" wide tape to prevent moisture penetration. It is highly advisable to insulate and tape the edges of the slab as well for best performance. Properly installed bubble concrete pads and insulation effectively reduce conductive and radiant heat losses.
Bubble vs Foam Board Insulation
Pro's:
1. Moisture resistance - unlike EPS and XPS foam board, bubble slab insulation absorbs no moisture and therefore experiences no performance losses over time.
2. Bubble insulation is a moisture barrier and uncoupling membrane in itself and, unlike the foam boards, does not require purchasing a separate product for his purpose.
3. Easy to install - long rolls are much quicker and easier to install than foam boards.
Con's:
The biggest disadvantage of bubble slab insulation is a lower R-Value (best is around 3.8, which is equivalent to 3/4" foam board). Projects requiring a high R-value insulation would either need to use multiple layers of bubble insulation or use foam board insulation instead. A combination of both is also possible.
