Longevity. Even under the best conditions, many outdoor structures will need regular maintenance and eventual replacement. The right materials can significantly extend service life, making higher initial costs worthwhile.
Structural integrity. In-ground concrete piers and wood framing, not full-depth foundations, typically support exterior decks and porches. Framing materials, connectors, and fasteners that can handle outdoor conditions are vital.
Future plans. If the deck or porch may eventually become an enclosed, conditioned part of the home, incorporating features now that will accommodate those future changes will save time, money, and materials over the long run.
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