Could you possibly share whatever information you might have on a product that is termite proof/termite resistant to insulate my slab on my building.
The only thing I have found somewhat useful is Cellofoam. It’s a EPS product that is infused with insecticide.”
Mike the Pole Barn Guru says:
Solution – Rockwool Comfortboard 80. Rockwool Technical Innovations released a bulletin in August 2019, wherein they had recently completed third party testing at University of Hawaii to determine termite resistance of stone wool insulation. Insulation samples were tested to AWPA E1-09, “American Wood Protection Association Standard Method for Laboratory Evaluation to Determine Resistance to Subterranean Termites”. Test involved exposing insulation samples to 400 Formosan subterranean termites for a 28-day period then measuring weight loss of material, termite mortality rates and visually evaluating sample damage. Results were then compared to a control sample of Southern Yellow Pine untreated and Southern Yellow Pine treated for termite resistance with ACQ, type D.
Test results indicated stone wool insulation proved to be termite resistant per this rigorous test making material appropriate for use under conditions of very heavy termite hazards. Laboratory observations made during testing moted termites initially investigated stone wool, but then covered it with sand within first week. This is an avoidance behavior evidenced by termites wanting to isolate something undesirable, such as an unacceptable food material. Material weight loss of stone wool was only 1.22% compared to 4.85% for treated wood and 50.92% for untreated wood. Both IRC (International Residential Code) and IBC (International Building Code) address foam plastic insulation use in areas where termite infestation probability is ‘very heavy’ and restrict its use when installed on exterior face or under interior or exterior foundation walls or slab foundations located below grade. To use foam plastics in these applications and geographies, it is required all structural members are made of non-combustible materials or pressure preservative treated wood, or an approved method of protecting foam plastics and structure from termite damage is used.
Most Builders Do Not Understand Condensation Control, Ventilation or Insulation Crucial to proper performance of climate controlled buildings of any sort is condensation control, adequate ventilation and insulation. Sadly, most builders do not understand how to come up with a proper design solution.
Reader AARON in WISCONSIN DELLS writes: “Hello, I was wondering if you had a minute for a quick question ? I have read posts for countless hours regarding vapor barrier between trusses and roof steel and I can’t find the answer I’m looking for. I’m building a 44×96 that will have in floor heat in South central Wisconsin (by Madison) so we have cold winters and humid summers. Walls will be spray foamed. I will be applying a vapor barrier (poly) to the bottom of roof trusses and then putting a metal ceiling on and spraying fiberglass insulation above the ceiling. Fully vented ridge cap and 2’ overhangs with vented soffits around the entire building. The builder did not put any vapor barrier down between the roof steel and the trusses so the steel is directly on the trusses. Could this end up creating a moisture issue or will I have enough air flow in the attic space that I do not need the vapor barrier between the roof metal and trusses ? Thank you very much for your time.” Thank you for reaching out to me Aaron, I am always available to answer questions. Your builder sadly did you no favors in not having a means to prevent condensation on your roof steel underside. It also requires having an actual thermal break, not just a vapor barrier. Your best solution now is to have two inches of closed cell spray foam applied directly to the underside of your roof steel, making certain they do not block ridge vents. Without this thermal break, expect to end up with damp insulation. If your builder installed vented soffits on your building’s end overhangs, you need to find a method to block them off – otherwise your attic will not vent properly. In regards to ceiling vapor barriers, Joe Lstiburek (building scientist and founding principal of Building Science Corporation) says plastic vapor barriers should only be installed in vented attics in climates with more than 8,000 heating degree days. Even in South central Wisconsin, you are not to this point. You’ll want to verify a correct ratio of air intake from soffits to air exhaust at ridge (chances are good your builder did not). At least 40% and no more than 50% of your attic’s net free ventilating area (NFVA) should be at the ridge. You may need to block off some of your sidewall eave vents to get the ratio correct. I would also recommend you blow in rockwool insulation in your attic rather than fiberglass. Fiberglass insulation loses R value when outside (attic) air temperatures are low and is also affected by even small amounts of moisture.