Q. What is the best decking material to use around pools? We have used CCA-treated southern pine, but this splinters within five years. We have also looked into plastic decking and commercial roof-top membranes. Both would put us over budget.

A.Craig Savage responds: In a word, our answer is masonry. Most of the decks we build sit on hillsides. This means the pool — a cistern built of rebar and gunnite — sticks out of the ground, and is supported on "table legs," or concrete caissons that typically run 50 or 60 feet down. Around this structure, we build a wooden deck on all sides. As a surface decking material, we always use some type of masonry. We typically use brick or sandstone flagstones. But slate or just plain concrete would do as well.

We hang the deck ledgers right off the pool and run our joists sloping at 1/8 inch per foot from the pool edge to the outside perimeter. We then deck the framing with pressure-treated plywood.

Over the plywood we lay down some type of rubberized membrane. We typically use Miradri (Mirafi, 3500 Parkway Ln., Suite 500, Norcross, GA 30092; 404/447-6272) — a rubberized asphaltic membrane with a paperbacked adhesive that sticks to the plywood. This comes in 3-foot-wide rolls and goes down fast.

Along the perimeter of the deck we run a plastic channel drain, such as NDS Micro Channel (National Diversified Sales, P.O. Box 6038, Camarillo, CA 93011; 805/389-6700). In section, this plastic drain material has the same dimensions as a 2x4. Along the top edge are slots, so we install it on edge, then float our masonry flush to the top, as shown in the illustration.

Craig Savage is a builder in Carpinteria, Calif.