AboutMorgan M. Audetat Expertise Radiant floor heating. Snow Melting. Boilers. Indirect water heaters. Tankless water heaters. Current owner BadgerBoilerService.com Minneapolis based mechanical contractor specializing in Mod/Con based, integrated heating systems. System design, consulting and technical training world-wide.
Currently designing hot water based heating and snowmelting systems for spaces ranging from 50 to 50m square feet. Consulting fees start at $500.00US
Experience 30 years. Organizations: Charter Board Member - Radiant Panel Association, former manufacturer of the first American-made wall-hung, sealed combustion condensing boilers, son and apprentice of mechanical & plumbing contractor.
Continuing Education: Uponor/Wirsbo advanced design school 2007, Power Limited License (low voltage controls) 40 CE credits 2005, B&G Little Red School House 1993, Tekmar Controls residential and commercial 1993, Division Manager and Advanced Hydronic Seminar Host for the first Hydronic Radiant Floor Distributor in the USA 1990, Hydronic Heating Association Workshop participant with Richard c. Bourne, PE spring 1988, Master Plumbing/Hydronic/Solar Course Red Rocks Community College 1987.
Education: B.S. University WI 1981, 26 yrs. continuing education.
Licensed CO, MN & WI. Home Inspection license WI exp.
Awards and Honors: My momma's favorite son.
Past/Present Clients: References upon request.
Expert: Morgan M. Audetat Date: 3/7/2008 Subject: insulation board gap on Badgerboilerservice.com
Question Mr Audetat,
I am a custom builder in North Carolina who has just read nearly every posting you have answered on this site. Thank you for volunteering your wealth of information. I noticed on your web-site that the photo of the basement slab prepped for concrete has a 6-8" gap where the Dow board stops before the outside wall. In my area the board is run to the wall per the city inspectors. Can you tell me what the reason for this gap is? Also, I am trying to decide in the framed section of my next house weather to use Ultra-fin or to use a product like Thermalboard. Is the "convection" principle behind the ultra fins more efficient or more comfortable or more anything than the typical staple up configuration? And lastly, given that I will be using an Engineered Pecan floor over the radiant; Would you advise using another installation method other than staple or nail to minimize the risk of damage to the Pex. Thanks in advance for your advice!
Answer The insulation gap was political. I did not sign off on it, but as the floor is 8 feet below grade it is not a major consideration. Tubing below a floor in cold climes should generally be in extruded aluminum panels, though finned and direct staple up systems work for certain applications, higher water temperatures (read higher fuel bills) always follow.
Talk to flooring manufacturers about design water temperatures. Dry surface mounted or sandwich system perform well at relatively low water temperatures and allow the flooring installer to see the sleeper he will nail to and the tubes he wants to avoid.
