Maintaining My Home

inadequate fall indicates a problem with the shape/slope of the substrate/framing under the deck

if the deck was constructed in recent years, call the contractor back. Recent work should be repaired by the contractor who carried out the original work

installation and/or repair of membranes is typically not a DIY job. Membrane manufacturers and suppliers typically train and license applicators in the use of their membranes. A warranty may only apply where application or repair is carried out by someone licensed by the supplier

if there is a habitable space beneath the deck, then work on the membrane and substrate will be restricted building work under the Building Act and anyone engaged to carry out this work must be a licensed building practitioner or be supervised by an LBP

if ponding has been a long-term problem and there is the possibility it may have resulted in leaks into the deck framing/structure, engage an experienced building surveyor for advice

clear the blockage

a single drainage outlet by itself is not good design – ideally, construct either an overflow or an extra outlet

designs for enclosed waterproof decks following Acceptable Solution E2/AS1 (8.5.6) must discharge water either (a) into a roof or gutter outlet with a minimum diameter of 75 mm with either an overflow or an extra outlet, with both outlets sized to take the full required capacity, or (b) via a scupper into a gutter or rainwater head