In-service moisture content of hardboard lap siding in southern Florida

Abstract

To evaluate the effect of backpriming on in-service performance,hardboard lap siding from one manufacturing plant was exposed on two test buildings in southern Florida for 29 months. The two buildings were identical, except that one had 0.3 m (12-inch) roof overhangs without gutters and the other had gutters but no roof overhangs. Siding installation was the same on both buildings and was essentially as recommended by the manufacturer. Laboratory tests revealed that edge swell and other properties of this particular siding were much better than required by industry standards. With only one exception, noticeable caulk seal failures either did not occur or were promptly corrected. All siding remained dry and in excellent condition over the exposure period. Some water intrusion occurred between some of the window units and trim. The siding system dissipated this water intrusion without suffering damage. Roof overhangs reduced moisture levels in the exterior millwork and trim, but did not appear to reduce the moisture content of this siding. Backpriming did not improve the performance of this particular hardboard siding nor did it lower inservice moisture content.

Citation

Carll, C.; Tenwolde, A.; Malinauskas, V.; Knaebe, M.; Sotos, P. G. 1999. In-service moisture content of hardboard lap siding in southern Florida. Durability of building materials and components 8 : service life and asset management : proceedings of the eighth International Conference on Durability of Building Materials and Components, 8DBMC : Vancouver, Canada, May 30-June 3, 1999. Volume one, Service life and durability of materials and components. Ottawa : NRC Research Press, 1999.:p. [680]-692 : ill.