How to Install Clad Windows

If you have a medium amount of do-it-yourself experience, you might elect to install clad windows on your own to save hundreds of dollars in contracting costs. The process requires at least two people, but your clad windows can be completed in a couple of hours per unit. Here's how.

1. Ready the opening with housewrap and pan flashing.

Cut a top tab that covers the clad window's top flange after the clad windows are installed. Use pan flashing to collect and drain any water. Use beveled siding and self-adhesive flashing tape, because it forms a seamless pan that contours to the sill.

2. Fold the top tab up.

First, cut across the header, then down the center. Staple the tabs down, then cut the top tab.

Make a horizontal cut and two angled cuts to the sill, then fold up the top tab, and tape it out of the way. Use beveled siding to create a sloped sill. After wrapping the opening, nail a piece of siding along the rough sill. Add the thickness of the siding to the height of the clad windows when framing the rough opening. Then add self-adhesive flashing tape.

3. Caulk, shim, and nail the window in place

Make sure there's a good seal around the flange and get the window fully nailed off before the caulk dries. Run caulk along the sides and top of the opening, but don't caulk along the bottom. A sealed bottom flange can trap water in the pan flashing. Then center the clad windows in the rough opening evenly.

4. Take the glass out before putting the window in.

Remove the sashes to make the clad windows easier to handle and to avoid breaking the glass. Keep the nailing flange tight to the sheathing at all times, and run shims along the side jambs every 8" to keep them square and straight. Nail the bottom flange only. Make sure the clad windows sills are level.