High Humidity Details

In areas of high humidity where solid sheathing is required:

Following are 4 different suggested methods of application to increase longevity:

1. Apply Certi-Last® pressure-impregnated treated shakes or shingles directly to the sheathing.(See Figure 23a)
2. Apply vertical strips over the sheathing in alignment with the rafters below, then place horizontal furring strips on top of the vertical boards. (See Figure 23b).
3. Apply horizontal furring strips to the deck, spaced at the exposure of the product.
4. A continuous ventilation product may be used beneath the Certi-label^TM roofing material (See Figure 23c).

Note: Good ventilation is essential. Ridge and soffit vents are recommended.

Note: the above figures are depicting a shake application - Do not interlay shingles with felt