Swamp cooler removal and roof patching for Phoenix homes

Evaporative coolers were the standard way to cool a Phoenix house for decades, and they still work well in the dry months before monsoon humidity arrives. Many homes built from the 1950s through the 1980s had one set on the roof, usually on a steel stand over a downflow duct cut through the ceiling. When owners added refrigerated air, the cooler was often just switched off and left in place, because taking it down meant someone had to deal with the hole underneath.

That leftover box keeps working against the roof. Supply lines weep, pans rust through, and the stand legs press into tile or foam under a few hundred pounds of steel and pads. The duct opening below is often blocked with nothing more than a scrap of plywood, a bag of insulation or a register cover. In winter that open duct pulls warm air out of the house, and in summer it lets attic heat drift back down. Our guide to keeping or removing a rooftop cooler goes deeper if you're still deciding.

Once the cooler and stand are down, the real roofing work starts. We pull out the old curb or wood frame around the duct and look at the rafters or trusses on either side. If the opening falls between framing members, we add blocking so the new decking has solid support on every edge. Plywood or OSB matched to the existing thickness goes in next, fastened to that blocking, so the patch sits flush with the deck around it and won't dip under foot traffic later.

Inside, the ceiling register usually stays put until you decide what to do with it. Some owners have a drywall contractor close it, others leave it as a return. When the cooler fed ductwork running through the attic, or a heat pump shares the same trunk line, your HVAC company handles the duct side. We coordinate the timing with them so the duct is capped or rerouted before we close the roof, and our work stays on the deck and above. If water has already rotted sheathing past the opening, our sheathing repair work covers the wider area first.

Tile roofs take the most care. The cooler usually sat above several rows of tile, and those pieces have often faded, cracked or slipped from their battens. We pull back the surrounding field, lay underlayment over the new decking, and lap it under the paper above and over the paper below so water sheds downhill. Then tile goes back, with cracked pieces swapped for matching profiles. Concrete tile fades in Valley sun, so when we can, we borrow spares from a hidden plane such as the back of a garage, which blends far better than a fresh tile off a pallet.

On a foam roof, we cut back the coating and foam in a square around the old opening and spray fresh foam to the same thickness, so no low spot forms. Base and top coats follow, feathered into the existing surface. Membrane roofs get a patch of the same material lapped well past the new decking, and shingle roofs get shingles woven in so the courses run straight. If the surrounding foam is already chalky, pairing the job with a fresh coat over the whole roof is worth considering.

The patch we redo most often was built from the top only: a sheet of metal screwed over the hole with roof cement smeared around the edges. Roof surfaces here can run 150 F to 170 F in July sun, so that cement shrinks, cracks and lets the first monsoon storm into the ceiling. Leftovers cause trouble too. A water line cut short and left to drip, or stand bolts pulled with their holes left open, become leak points. We cap the line properly and flash every hole the stand left behind.