The minimum insulation thickness that kills condensation — in seconds, on your phone, offline.
A brand-neutral mechanical-insulation calculator for HVAC engineers and contractors. Condensation control, heat loss/gain, and safe-touch surface temperature for pipes, ducts, and flat surfaces.
Download on the App Store One-time purchase — no subscription, no ads.Every mode shares the same ASTM C680-style steady-state solver.
Enter operating temperature, ambient temperature and RH. Get the dew point, the minimum thickness that keeps the surface above it, and your margin — colour-coded green, amber, or red.
Pick a thickness and get heat flow per unit length or area, the outer surface temperature, and an automatic condensation-risk flag.
Find the minimum thickness that keeps a hot surface at or below a burn-safe limit — 60 °C / 140 °F by default, and adjustable.
The details that separate a real calculation from a rule of thumb.
The industry reference for condensation control has never had a good native mobile equivalent, and most insulation apps on phones are tied to a single manufacturer's product line. InsulSizer is brand-neutral and multi-material — it runs in your hand, on the roof, in the plant room, with no signal and no login.
It is also the fifth tool in a family built the same way: use the dew point from AirCalc Pro, size the pipe in HydroSizer and the duct in DuctSizer Pro, then insulate them here.
Metric or imperial, in your language, without an internet connection.
Available in English, Español, 中文（简体）, Português (Brasil), 日本語, 한국어, and Tiếng Việt.
Engineering note: InsulSizer is a calculation aid for preliminary sizing and field estimation. Always confirm the final specification against the manufacturer's current published data for the exact product being installed, and against the governing project specification and local code.