My Attached Porch Leaks

Flashing

• One of the most important elements of any porch or exterior add-on for the home is flashing. Flashing comes in a variety of formats but it covers any inside or outside corners where water would otherwise have a chance to penetrate, such as around windows, around doors, inside corner seams and the ledger board that the framing of the porch is attached to, which in turn is attached to the house. Without flashing protecting these areas, water will penetrate.

Caulking

• Part of installing siding as well as flashing is including the proper kind of caulk. Siding needs caulking, flashing needs caulking, and certain types of decks need caulking where the boards meet the wall of the home. Each different installation protocol calls for a different type of caulk, and if you don’t follow manufacturer recommendations for the installation, you will have leaks in various areas, such as around the windows and doors or any cuts into inside corners. Silicone is the preferred type used for exterior settings, but always check with the manufacturer's installation instructions.

Install It Right

• If the installation instructions aren’t followed to the letter, leaks will occur. For example, if you don’t follow the deck planking recommendations about necessary space between the planks and the wall siding, the pressure from the wood when it swells will cause the siding to crack, thus providing water a place to penetrate. Similarly, if you don’t flash around the door, the water will penetrate through the door and cause damage.

Waterproofing

• For siding installations on add-on porches, you need to ensure that proper waterproofing methods are used. Your type of siding will have a recommended waterproofing protocol based on manufacturer guidelines. While tar-based felt paper is the most common, plastic and composite housewraps are also used. Always refer to the siding manufacturer's recommendations, because a siding installation without the proper type of waterproofing will be sure to leak.