Your concern about splinters from wood outdoor furniture is valid, but the good news is that some wood types and treatments are significantly smoother than others. The key factors are wood grain, density, and finish.
Dense hardwoods with tight, fine grains are naturally smoother and more splinter-resistant. Top choices include teak, shorea, and eucalyptus. These woods have minimal pores and a naturally high oil content, resisting moisture that can cause cracking and raised grain. In contrast, softer woods like pine are more prone to splintering unless properly treated.
The most crucial element is often the finish. All outdoor wood, regardless of type, benefits from proper sanding and sealing. Look for furniture labeled "kiln-dried" and "sanded smooth." A high-quality sealant, UV-resistant oil, or marine-grade varnish creates a protective barrier that locks down wood fibers, preventing them from lifting and forming splinters. Regularly maintained sealed furniture remains smooth for years.
For ultimate peace of mind, consider thermally modified wood or acetylated wood (like Accoya). These advanced processes permanently alter the wood's cell structure, enhancing dimensional stability and creating an exceptionally smooth, durable surface highly resistant to splinters and decay.
Pro Tip: Run your hand along the furniture before purchasing. It should feel completely smooth with no rough patches. Consistent maintenance with appropriate oils or sealants is essential to preserve that smooth, splinter-free surface season after season.