It’s time once again to take a look at a few interesting new building products. I recently spotted two potentially useful ventilation products — a new type of ERV(ERV). The part of a balanced ventilation system that captures water vapor and heat from one airstream to condition another. In cold climates, water vapor captured from the outgoing airstream by ERVs can humidify incoming air. In hot-humid climates, ERVs can help maintain (but not reduce) the interior relative humidity as outside air is conditioned by the ERV. and a fan for ventilating small rooms — and two products that are destined for attics — an insulating “hat” for recessed cans and a ventilation baffle that can be installed between rafters. I will also report on JointSealR, a tape distributed by Owens Corning for taping XPSExtruded polystyrene. Highly insulating, water-resistant rigid foam insulation that is widely used above and below grade, such as on exterior walls and underneath concrete floor slabs. In North America, XPS is made with ozone-depleting HCFC-142b. XPS has higher density and R-value and lower vapor permeability than EPS rigid insulation. seams.