Deck Siding Acting As Flashing

How to flash a deck ledger board.

Deck siding acting as flashing.

Installing z flashing to prevent water from seeping behind the deck s ledger board and rotting the board and the siding the flashing must cover the top of the ledger board and bend over the edge. If you re just trying to buy a few years until a new deck can be built some tubes of high quality silicone caulk and whatever other tricks it takes to divert water to the face of the ledger can buy you some time. Reusing what you remove keeps the job green and saves the trouble and expense of matching the finish. Infiltrating rainwater can travel downward sideways and even upward so special flashings must be used.

Nail the z flashing over the top of the ledger. Slip the back flashing under the siding at least 3 at the top and the sides. A simple metal or plastic cap flashing is probably adequate to flash a deck ledger in a dry climate while the 3 layer system described in this video is suitable for high rainfall and damp climates. As you can see from the diagram and the photo flashing must be done in layers.

Install flashing that is made for ledgers. Learn how to inspect the proper installation of the deck ledger board flashing as a certified home inspector. Start by making an outline on the siding where you want to position the ledger board. The level of water resistance you need to achieve when flashing a deck ledger will depend on the rainfall and how dry your climate generally is.

Relying on sealed counter flashing isn t ideal but neither is marrying your cladding to your braced walls in one product. If you cut out your siding to install a ledger board careful steps must be taken to ensure that moisture cannot reach your house. Flashing consists of metal which is durable enough to be exposed to sunlight and mechanical wear and tear plus peel and stick membrane like vycor grace construction products. Attach the ledger board.

Then slip flashing behind the siding covering the top edge of the ledger. Slip the flashing behind the trim. The best way to think about it to visualize what a drop of water will do as it hits the deck and moves towards the house. First the rain hits the siding then it gets to the house wrap then it hits the drip cap flashing and runs out away from the house.

Make the outline large enough to include space for the deck boards on top the ledger and any trim boards on the sides. You may need to pry out the siding first. Snap a chalk line cut out the siding and tack up the ledger board. Cut it for flashing and you structurally damage the wall.

Often the t 111 is acting as the braced wall panel. Though it will take some dismantling and perhaps a replacement deck board or stick of siding following the recommended practices for installed ledger flashing based on your exterior cladding is the best approach.