- Author
- Zarr, R. R. | Burch, D. M. | Faison, T. K. | Arnold, C. E.
- Title
- Thermal Resistance Measurements of Well-Insulated and Superinsulated Residential Walls Using a Calibrated Hot Box.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Journal
- ASHRAE Transactions, Vol. 92, No. 2, 604-619, June 1986
- Report
- PO-86-12,
- Keywords
- thermal resistance | walls | calibrated hot box | heat transfer
- Identifiers
- National Bureau of Standards Calibrated Hot Box (NBS CHB)
- Abstract
- Thermal resistance measurements of two highly insulated residential walls are made using a calibrated hot box operated under winter and summer climatic conditions. The well-insulated wall consists of two insulated wood-frame sections with staggered framing, having a nominal thermal resistance of R-27. The superinsulated wall is identicial in construction, except for additional insulation placed between the two wood-frame sections increasing the wall thermal resistance to a nominal value of R-39. The measured thermal resistance for both walls is examined as a function of mean wall temperature and compared with predictions using the ASHRAE parallel-path method, the ASHRAE isothermal-plane method, and a finite-difference model with temperature-dependent thermal conductivities. Good agreement between measured and predicted values is obtained using both ASHRAE methods and the finite-difference model. At mean wall temperatures above 40 F, the ASHRAE parellel-path method tends to overpredict, while the ASHRAE isothermal-plane method tends to underpredict the overall thermal resistance. The effects of the compression of glass-fiber blanket insulation and nail penetrations on the overall thermal resistance are investigated.