| Cold Floors – Bonus Rooms & Beyond In winters, cold floors are not just found in bonus rooms (rooms over garages) anymore; today's home designs are becoming more ambitious, with new opportunities for cold floors to develop over such unconditioned spaces as porches, crawl spaces, and even floors cantilevered beyond the exterior wall of the building. The push for more durable floor finishings like hardwood & ceramic tile are making the problem even more common because these materials have a low R-value. Most builders understand that bonus room floors require substantially more attention, if these rooms are to be made as comfortable as the rest of the house. Often, standard construction practices simply do not provide a sufficient level of performance or durability to justify the additional cost. The end result is a compromise; the builder does his best to keep the job affordable for the homeowner, and the homeowner accepts that the bonus room will not be as comfortable as the rest of the house. Why the Floors are Cold? Even with building codes in many areas dictating that these floors be insulated to R-25 (RSI-4.3), it is common to find floors that are 10° F (5.5º C) cooler than the room. Why? Because it is difficult to install an insulation batt so that it is in contact with, and stays in contact with, the entire floor above. Unless continuous contact can be maintained, void spaces will exist between the batt insulation & the floor above. These void spaces can range in size from small pockets to, in some cases, the entire length of the room. Cold air that penetrates the insulation can flood the void space between the insulation and the floor, rendering the insulation ineffective. Complicating matters is the necessity to accurately install the insulation around bracing and bridging between joists. The use of air permeable friction fit insulation system relies on an effective air barrier material being installed on both the underside of the insulation and at the exterior wall, at a cost that many builders and homebuyers cannot justify. Heated Plenums Some designers and builders have tried to overcome the weaknesses of this system through the use of a heated plenum space: a dropped ceiling is installed in the garage and insulated with a fiber batt. Heated house air is then ducted into the space created under the floor. While this is a more reliable means to keep the floor warm, experience proves it does not address all related problems. When water pipes are run within the plenum, frozen pipes are still commonplace. One reason is that there is no code requirement for proper insulation & air-sealing at the exterior wall of the heated plenum, therefore cold air infiltrates under certain weather conditions. In the failure to properly air-seal, the insulation allows the heated humid air to move through it and come in contact with the exterior plenum wall. This can result in condensation in the insulation and on the cold exterior plenum wall, creating the potential for a long-term structural problem. To compound the issue, if a return air duct is installed to recycle the heated air, it runs the risk of conveying glass-fiber particles to the house. While it is possible to design the heated plenum system to prevent these problems, the amount of labor involved makes the solution cost-prohibitive. Instead, builders may opt to ignore the additional detailing necessary in order to get the system to work. The inferior design will cost the building owner in higher energy bills for the life of the building. Air Barrier Systems The ideal means to supply occupant comfort to bonus rooms is to install a combined insulation and air barrier material in direct contact with the underside of the floor. This type of insulation prevents conductive heat loss from the room above. And unlike the use of a heated plenum, this system does not require a continuous source of heat, or risk either condensation damage or reduced air quality. Icynene® Icynene® is a perfect solution for bonus rooms and floors exposed to cold air. It is a low-density (0.5-lb/ft3) combined air barrier and insulation that forms a continuous, reliable bond without sagging, settling, shrinking, or debonding from the substrate. Icynene® helps reduce the possibility of HVAC short-circuiting and the need for heated plenum systems. Thousands of floors over porches, garages, crawl spaces & cantilevers have been successfully insulated & air-sealed with Icynene® and many more existing cold floor issues have been resolved by an Icynene® retrofit such as the village at Fox Point. The Village at Fox Point is a 56 building, 450 unit housing project originally constructed in 1949. When fiberglass failed to correct the tenant's complaints about cold drafty floors, high heating bills, poor indoor air quality and a moldy crawlspace area Icynene® was selected to correct these problems. Learn how Icynene® solved these “sick building issues”. Icynene® created a healthy indoor environment, delivered 29% in energy savings as well as helped in mold remediation in the crawlspace. |